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CURRENT HONOURS PROJECTS IN PHYSIOLOGY

Honours Projects 2013 (PDF with all the projects below)

OFFERED PROJECTS IN 2013

MUSCLE CELL FUNCTION LABORATORY, Anderson Stuart Bldg, Room N421 Telephone: +61 2 9351 4602

Professor David G. ALLEN

The Muscle Cell Function laboratory is concerned with the regulation of calcium and other ions in cardiac and skeletal muscle cells.

Project Title: Muscle fatigue (Dr Sofie Trajanovska).

The lab is developing a new approach to studying muscle fatigue which involves fatiguing whole muscles in the anaesthetized mouse. The advantage of this approach is that the muscles are intact and have their normal blood supply. We use genetically encoded calcium sensors (cameleons) to measure intracellular calcium using the the new multiphoton confocal microscope. Immediate aims are to understand the mechanism(s) of fatigue in this preparation by measuring both intracellular calcium and metabolic changes.

Project Title: Pacemaker cells of the heart (Dr Yue-kun Ju)

We previously demonstrate that intracellular Ca2+ plays an important role in cardiac pacemaking. Recently we have discovered a store-operated Ca2+ channel in sinoatrial node of the heart and the presence of IP3 receptors acting as another source of calcium release from the SR. The present project will assess the role of store-operated calcium channels and IP3 receptors in determining calcium regulation in the mouse sinoatrial node. This investigation aims to improve our understanding of mechanism of normal heart beat as well as its involvement in cardiac arrhythmias.

Direct enquiries can be made by email to: Professor David Allen - david.allen@sydney.edu.au

ANDROLOGY RESEARCH GROUP , Anderson Stuart Bldg, Room E216 Telephone: +61 2 9351 2514

Supervisor: Dr Stephen Assinder

Prostate disease is very common in the ageing male. Prostate cancer is the most commonly diagnosed cancer in men and second most frequent cause of cancer-related deaths. It is estimated that there is at least 1 death every 4 minutes worldwide attributed to prostate cancer. A common treatment option is the removal of androgens either by chemical or physical castration. Unfortunately many tumors develop resistance to this therapy (androgen independent or castrate resistant prostate cancer), and ultimately the patient will die.

Our research is focused on:

1. Understanding how the loss of structural proteins involved in organization of the cell cytoskeleton contribute to the development of prostate cancer.

2. Endocrine regulation of prostate cell proliferation. In particular we are interested in how various hormones and cytokines regulate prostate cancer growth.

Project Descriptions:

Project Title: Sprouty and male reproductive physiology. FGF is an important regulator of the development of the male reproductive tract. FGF signalling is known to be regulated by suppressor proteins, including sprouty 1 (SPRY1) and 2 (SPRY2). This project will study development of male reproductive tract, spermatogenesis and prostate pathology in mouse models deficient in sprouty expression (in collaboration with A/Prof Frank Lovicu). Histology, stereology as well as molecular biology techniques will be employed.

Project Title: The actin cytoskeleton, TGF-b and prostate cancer. The cytokine TGF-b normally acts to suppress cell proliferation. As such, during early stages of prostate cancer it is tumour suppressive. However, during later stages, and with constitutive expression of H-Ras, there is a switch from tumour suppressive to oncogenic actions of TGF-b. This is associated with a SMAD independent signalling pathway activated by this cytokine. It is hypothesized that the loss of a stable cytoskeleton that occurs due to suppression of several actin binding proteins can promote this switch in TGF-b action. In this project the roles of Filamin A, tropomysins (including a novel splice variant of Tm1 – Assinder et al. 2010; Mol Carcinogen. 49: 525-531) and of transgelin, an actin binding and stabilizing protein, expression to occur with prostate cancer progression (Prasad et al. 2010; Cell Tiss Res. 339: 337-47) will be studied. This project will employ many techniques including cell culture proliferation assays, RT-PCR, real time PCR, siRNA knock downs and western blot.

Project Title: Oxytocin and prostate cancer cell metastasis. Endocrine-related prostate cancer is commonly treated by androgen ablation (castration). Unfortunately advanced prostate cancers become resistant to treatment (CRPC) and inevitably result in death. Our work has led us to propose that analogues of the hormone oxytocin (OT) might present an alternative treatment option. If proved so, they could rapidly be brought to approval for treating CRPC as OT analogues are already used in birth management. In ovarian cancer, oxytocin has been shown to inhibit metastasis by increasing expression of the cell-cell adhesion protein E-cadherin, whilst suppressing the secretion of matrix metalloprotease and cell migration. This project will test if similar effects are elicited by oxytocin in prostate cancer cell lines. This project will employ many techniques including cell culture, RT-PCR, real time PCR, western blots and xymography.

Project Title: Targetting the copper transporters to improve prostate cancer treatment. Some of the most successful chemotherapeutic agents for use in oncology are platinum-based drugs such as cisplatin. Drugs with a central complexed platinum ion are delivered into cells by the copper transporters (Ctrs). The native ion for transport by the Ctrs is reduced copper however these receptors can also transport other divalent metal cations such platinum. Copper transporter-1 (Ctr1) is the predominant copper transporter whilst Ctr2 is less well understood. Both can transport platinum-based drugs. Prostate cancer is notoriously recalcitrant to conventional chemotherapies, and cisplatin is not useful for treatment of prostate cancer due to insensitivity. This project will:

1) Assess copper transporter expression and regulation in normal prostate tissue and prostate cancer cells.

2) Determine the signalling systems down-stream of copper transporters in prostate cancer cells.

This project will employ many techniques including cell culture, RT-PCR, real time PCR, siRNA knockdowns, western blots, flow cytometry, luminex protein array assays.

This project is in collaboration with Dr Stuart Fraser.

Direct enquiries for all projects can be made by email to: Dr Stephen Assinder – stephen.assinder@sydney.edu.au

NEUROPSYCHIATRY LABORATORY, Brain and Mind research Institute

Prof Max Bennett, Email: max.bennett@sydney.edu.au

The main research interest of our laboratory is to use completely new technologies to identify what has gone awry in the brain in conditions of stress leading to major depression and in schizophrenia. Animal models (from mice to zebra fish) are then used to help identify the cellular/molecular mechanisms involved and novel chemical therapeutics designed to put aright what has gone wrong.

AUDITORY NEUROSCIENCE LABORATORY, Anderson Stuart Bldg, Room N438, Telephone: +61 2 9351 3205

Associate Professor Simon CARLILE directs a multi-disciplinary research group aimed at understanding the mechanisms underlying our perceptions of auditory space. Research projects involve bioacoustics, neural coding, behavioural/psychophysical studies, computer simulations and digital signal processing. Areas of current research include the bioacoustics and psychophysics of our perception of spatial location including the influence of head movements and the integration of auditory and visual information.

Project Title: Auditory spatial perception and the cocktail party problem.

Much of our research focuses on the so-called "cocktail party" problem. That is, how are we able to hear out a talker of interest from a noisy backdrop of other sounds competing for our attention? While this is a significant signal processing problem, it is not an effortful task for most people with healthy hearing. However, even mild hearing loss severely impairs an individual's ability to do this effectively, and the most advanced hearing aids are unable to confer much perceptual benefit in these conditions.

We take a multidisciplinary approach to the issue, blending bioacoustic and psychophysical methods with computational modelling to identify the cues which the healthy auditory system uses to selectively focus attention in acoustically lively environments. This includes the examination of a number of basic perceptual questions that have implications for the manner in which much of this information is processed and integrated with other spatial senses (vision in particular). Additionally, we are interested in the mechanisms by which the auditory system accommodates to changes in the inputs produced by age-related changes in ear shape and sensitivity. The outcomes of this research are informing the design of next generation hearing aids.

Project Title: Perception of auditory motion

Our sense of auditory motion can be induced either by the motion of our own bodies through an environment containing stationary sound sources, or by our ability to detect and track motion of the sound sources themselves. In most everyday environments, we encounter a complex mixture of both. ANL is currently conducting a range of bioacoustic and psychophysical studies that examine this little understood perceptual-motor capability. As this basic function is known to be degraded in individuals with certain neurological disorders, among them schizophrenia, this research also has implications for the development of a predictive clinical test for these illnesses. Our preliminary work has uncovered both surprising similarities to and differences with the way in which we perceive moving visual stimuli, thereby contributing to both integrated and differentiated models of spatial motion.

Direct enquiries can be made by email to: Associate Professor Simon Carlile - simonc@physiol.usyd.edu.au

EPITHELIAL TRANSPORT LABORATORY, Medical Foundation Building, Room 230, 92-94 Parramatta Rd Camperdown, Telephone: +61 2 9036 3314

Dr Anuwat Dinudom and Professor David I. COOK

The Exocrine Physiology and Biophysics Laboratory investigates the cellular mechanisms that control ion and fluid transport in epithelium lining the kidney, gut, lung and exocrine glands. Current studies are focused on elucidating the mechanisms by which protein kinases regulate activity of the epithelial Na+ channel (ENaC) and elucidating the cellular mechanisms that underlie the disturbance of Na+ absorption and Cl- secretion in the lung caused by H5N1 avian influenza virus and H1N1 human influenza virus. Discoveries from our laboratory include, the role of ubiquitin protein ligases Nedd4 and Nedd4-2, G protein-coupled receptor kinase GRK2 and the kinase Akt1 on the regulation of ENaC, and the mechanism by which H1N1 human influenza virus inhibits Na+ absorption in the respiratory epithelium.

Our laboratory (PC2 facility) is located on Level 2 of the Medical Foundation Building. A range of techniques and equipment, including molecular biology, electrophysiology (patch-clamp and Ussing chamber), cellular ion imaging and tissue culture are available in house.

In 2013 we offer two projects.

Project title: Regulation of the epithelial Na+ channel by protein serine/threonine kinases

The epithelial Na+ channel, ENaC, is a Na+ selective anion channel that is expressed in the kidney, collecting duct, distal colon, lungs and excretory ducts of salivary glands. ENaC plays a critical role in the maintenance of Na+ and fluid homeostasis and, consequently, the regulation of plasma volume and blood pressure. Activity of ENaC is tightly regulated by physiological factors such as hormones and growth factors via cellular mechanisms that involve protein kinases. Apoptosis signal-regulating kinase 1 (ASK1) is a MAP kinase kinase kinase that mediates the cellular signalling response to oxidative stress. ASK1 has been implicated in pathogenesis of cancer, diabetes, cardiovascular and neurodegenerative diseases. Preliminary data from our laboratory suggest that ASK1 is a negative regulator of ENaC. This project aims to investigate the cellular mechanism by which ASK1 inhibits ENaC and elucidate the physiological role of ASK1 in the regulation of Na+ homeostasis.

Project title: Regulation of the epithelial Na+ channel by the Zinc transporter ZnT-1

This project aims to investigate a novel regulation of the epithelial Na+ channel (ENaC) by ZnT-1. ZnT-(Slc30a1) is the only member of the putative zinc transporters family that is expressed in most tissues and can be found in epithelial cells, including the colon, the kidney and the lungs, tissues where the activity of ENaC is crucial. Recent studies indicated that ZnT-1 is a modulator of the Raf/Ras/ERK MAP kinase signalling system. In cardiac myocytes, activity of ZnT-1 protects the cell against ischemia reperfusion and stimulates T type calcium channels by a mechanism that involves Ras/Raf/ERK signalling cascade. Little, however, is known about the role of ZnT-1 in epithelial ion transport. Data from our laboratory suggest that a number of ENaC’s modulators regulate the channel via ERK1/2 signalling system and that H-Ras down-regulates ENaC via the Raf/ERK1/2 signalling cascade. In this project, epithelial cells in culture will be used to elucidate the role of ZnT-1 in the ERK mediated modulation of ENaC. For that purpose the cells will be transfected with ZnT-1, or its fragments, and ENaC activity will be evaluated by measuring short-circuit current across the epithelium. Inhibitors, siRNA and dominant negative mutants will be applied to decipher the underlying molecular mechanism of ZnT-1’s involvement in the regulation of ENaC.

For more information please contact Anuwat Dinudom anuwat@physiol.usyd.edu.au

DEVELOPMENTAL PHYSIOLOGY LABORATORY, Medical Foundation Building, Room 232, 92-94 Parramatta Rd Camperdown, Telephone: +61 2 9036 3312

Dr Margot DAY

Roughly 3% of babies born in Australia result from assisted reproduction involving fertilization and then culture of the embryo in vitro. It is known that the embryo culture environment causes significant alterations in gene expression, epigenetics, metabolism and cell proliferation during preimplantation development and that these alterations may have effects on later life.

Our studies aim to help us to understand the impact of the culture environment on pre-implantation embryonic development in order to improve reproductive outcomes. We study the physiological processes involved in fertilization of the oocyte and proliferation of the cells in the preimplantation embryo.

To do this we use a range of techniques including in vitro fertilization, isolation and culture of preimplantation mouse embryos, gene expression, cell signalling, electrophysiology and live cell imaging.

Honours projects are available on the following topics:

o The mechanisms by which the amino acids improve blastocyst development in vitro.

o The role of cell cycle regulated K channels in proliferation of embryonic cells.

o Which growth factors are important for preimplantation development and how they can be used to improve development of embryos in culture.

Direct enquiries can be made by email to: Dr Margot Day - margotd@physiol.usyd.edu.au

BLOOD CELL DEVELOPMENT LABORATORY, Medical Foundation Building, Room 233, 92-94 Parramatta Rd, Camperdown, Telephone: +61 2 9036 3313

Dr. Stuart FRASER

Copper, Macrophages and Mammalian Evolution.

Copper is essential for cell function and survival. Copper is brought into cells via the copper transporters CTR1 and CTR2. We have found that the genes encoding these proteins have a unique genomic organisation in mammals compared to non-mammalian species. We want to ask, what effect does this genomic organization have on being a mammal? The cell type thought to express CTR1 and CTR2 at highest levels is the activated macrophage, a critical component of the immune system. Are there copper-dependent aspects of the immune system that have helped mammals to evolve separately from non-mammalian species? What has driven this evolutionary step?

Methods to be employed include; cell culture, protein expression analysis, confocal imaging, flow cytometry, bioinformatics and comparative analysis with mammalian and non-mammalian model systems.

Characterising a newly discovered cell type in the yolk sac.

The yolk sac is a thin membrane that surrounds the developing embryo supplying it with nutrients from the maternal side. The yolk sac is also the first site of blood cell production, an essential step in embryogenesis. To dissect the role of the yolk sac in development, we have developed a system to identify and separate all of the major cell type in this organ namely the blood cells, endothelial cells and mostly recent the outer layer of epithelial cells. Surprisingly, we have found a new cell type that expresses both epithelial and blood cell markers and which we believe may reside within the epithelial layer. This project will look at several important questions. 1) What is this cell type? 2) How does it develop as the embryo matures and 3) what is the function of this cell type during embryogenesis?

Methods to be used include; embryo dissection, flow cytometry, confocal imaging, transgenic reporter mouse analysis, gene expression analysis and cell culture.

Direct enquiries can be made by email to: Dr. Stuart Fraser-

stuart.fraser@sydney.edu.au

LIPID METABOLISM LABORATORY, Anderson Stuart Bldg, Room N401

Telephone: +61 2 9351 2514

Dr Andrew HOY

The Lipid Metabolism laboratory is concerned with the mechanisms linking perturbed lipid metabolism and a variety of pathologies.

Project Title: Breast cancer fatty acid metabolism

The lab has an interest in tumour metabolism as it has the potential to be a unifying therapeutic target. This is because all tumours require the same building blocks to sustain proliferation, i.e. lipids, amino acids; irrespective of the driver mutations that instigate tumourigenesis. Fatty acid metabolism is the poor cousin of tumour metabolism, compared to glutamine and glucose. Yet, obesity is a major risk factor for breast cancer and obesity is characterised by dysfunctional fatty acid metabolism. Therefore, the aims of this project are to characterise the fatty acid metabolism of breast cancer cells and identify key regulatory pathways for future validation as therapeutic targets.

Project Title: Linking lipid droplet metabolism with mitochondrial oxidation in skeletal muscle

Lipid accumulation in skeletal muscle is a characteristic of insulin resistance, the pre-type 2 diabetic state. The vast majority of lipid is stored as triacylglycerols in lipid droplets within cells. These lipid droplets are closely located to mitochondria, whose dysfunction has been proposed to participate in insulin resistance. The present project will assess fatty acid metabolism, including catabolic and storage pathways, in primary muscle cells from mice lacking the lipase responsible for the breakdown of triacylglycerols, ATGL. This investigation of the role of ATGL in the oxidation of intracellular and extracellular fatty acids will improve our understanding of the mechanisms of lipid accumulation in skeletal muscle.

Direct enquiries can be made by email to: Dr Andrew Hoy – andrew.hoy@sydney.edu.au

LABORATORY OF DEVELOPMENTAL NEUROBIOLOGY, Anderson Stuart Bldg, Room N663, Telephone: +61 2 9351 4352

Dr Catherine A. LEAMEY

Email: cathy@physiol.usyd.edu.au

Neural connections underlie every aspect of our behaviour. Understanding how the right sets of connections form in the developing brain, and the consequences of when these circuits wire together improperly, is the focus of work in our laboratory. Knowledge of the processes that regulate neural development has important implications for the development of treatments for early onset brain disorders such as autism, Rett’s syndrome and mental retardation, and to promote regeneration following injury.

A large body of research has demonstrated that the patterns of connections which ultimately form are a product of both genetic factors and environment/experience. The structure of the visual pathway makes it particularly suitable for investigating the roles of specific proteins in the assembly and function of neural circuits. We have recently discovered that a family of molecules, known as the Ten-ms or Teneurins, play important roles in wiring up the visual pathway: in the absence of any one of them, the uncrossed retinal projection, critical for binocular vision does not from appropriately. The defects are distinct for each family member indicating complimentary functions in the formation of binocular projections. The miswiring present in the knockout strains leads to behaviorally measureable visual deficits.

Successful applicants will join our team of researchers using molecular biological, neuroanatomical, physiological and behavioural paradigms to investigate mechanisms of brain wiring and the consequences of its miswiring. Specific projects include:

1) Downstream mediators of Ten-m function: We have recently identified candidates for Ten-m function and obtained mice where these genes are mutated. Anatomical and functional analyses of these animals present provide excellent opportunities for Honours projects.

2) Mechanisms underlying recovery of vision in Ten-m3 KOs: The misalignment of projections present in Ten-m3 KOs leads to a form of functional blindness. Recent data suggests that enhancing the animals experience via enrichment can lead to a recovery of vision, possible via reduced inhibition. Projects exploring this important research avenue also present very promising Honours projects.

3) Ten-ms at synapses: Ten-ms may be able to modify the growth of both pre-synaptic and post-synaptic structures, and may also modify synapses themselves. A good model for this is the neuromuscular junction. This project is offered in collaboration with Drs Phillips, Protti and Sawatari.

4) The impact of the deletion of Ten-m4 on visual behaviour and function: We have good evidence of a neuroanatomical defect in Ten-m4 KOs. The exploration of its impact on visual ability and behaviour presents an additional avenue for an Honours project.

Some of these are offered as collaborative projects in association with Dr Atomu Sawatari’s laboratory. Other projects may also be available on request.

Direct enquiries can be made by email to: Dr Cathy Leamey - cathy@physiol.usyd.edu.au

VISUAL NEUROSCIENCE RESEARCH GROUP, Save Sight Institute, Sydney Eye Hospital, Discipline of Physiology.

Prof Paul R. Martin

We study the connections of neurones in the retina and processing of visual signals in the brain. Our special interests are colour vision and high-acuity (foveal) vision.

Our laboratories are part of the Australian Research Council Centre of Excellence in Vision Science. In 2013 qualifying students are offered top-up scholarships, travel and other support from a strong research network involving labs in Sydney, Canberra, Brisbane, Melbourne, and Perth (for more details see www.vision.edu.au)

Colour vision is a very important capacity of animal visual systems, enabling objects to be distinguished by their spectral (wavelength) reflectance. The cell types and pathways involved in transmitting colour signals in humans and other primates are however poorly understood. We study this question by measuring responses of neurones in the primate brain using single-cell and multi-cell array recording methods.

High-acuity vision depends on a specialised region of the retina called the fovea ("pit"); this region is only present in primates among mammals. An important disease affecting the fovea is age-related macular degeneration, and understanding the wiring diagram of the fovea can help us understand why this disease affects the fovea specifically. We study this question using high-resolution light microscopy and immunochemical methods to identify cell pathways in the retina and their connections to the brain.

PROJECTS :

1) Colour pathways in the thalamus. You will join our team of electrophysiologists to measure single and multi-cell activity in primate brains. We have discovered that on part of the visual thalamus which transmits "blue" colour signals is also involved in brain pathways controlling slow-wave oscillations in sleep, anaesthesia and epilepsy. You will learn modern electrophysiological methods to record and understand how networks of nerve cells work to control brain rhythms.

2) Parallel pathways in human and non-human primate retinas. You will help to expand and develop our new methods for identifying nerve cell connections in the fovea of human donor retinas and retinas of non-human primates. You will learn single-cell injection and immunochemical methods to identify and characterise the cell populations that serve high-acuity pathways in the fovea.

for more information please contact Paul at prmartin@physiol.usyd.edu.au

VITAMIN D, BONE AND SKIN LABORATORY, Anderson Stuart Bldg, Room N543, Telephone: +61 2 9351 2561

Professor R.S. MASON and her group study the endocrine and local regulation of bone turnover and the role of vitamin D compounds in protection from UV irradiation in skin.

Current projects in bone and mineral include studies on regulation of bone turnover by calcium and other agents, including potentially novel agents to treat osteoporosis.

The area of vitamin D and skin research interest is mechanisms of skin cell protection from ultraviolet irradiation and ways of enhancing this.

Projects:

Role of Vitamin D and other compounds in protection of skin cells from UV
Our group has shown that vitamin D compounds, which are well known to be made in skin, have an important physiological function in skin to protect skin cells from the damaging effects of UV radiation. We have also shown that several types of DNA damage is reduced in skin cells and animal and human skin after UV when active vitamin D-like compounds are given immediately after irradiation and that these compounds protect from UV induced skin cancers (eg Dixon et al. Cancer Prev Res 4: 1485-94, 2011). The project will examine some likely mechanisms of action of the vitamin D compounds and other agents which act like vitamin D. These agents could potentially be used in sunscreens and after-sun preparations to reduce UV damage.

Mechanisms of action of calcium-like agents to enhance bone mass and reduce risk of fracture
Strontium is effective in reducing fractures in older people, but its mechanism of action was unclear. Our group has shown that strontium and other calcium-like compounds, including a reduce the signals for bone resorption, stimulate bone cell anabolism and improve the ability of bone-forming cells to withstand stress (Rybchyn et al. J Biol Chem 286:23771-23779, 2011). We have evidence that strontium acts, at least in part, through the receptor and cell signal pathway which mediates calcium responses in bone. There are other agents which could activate this pathway in slightly different ways and thus prove even more effective at adding bone and reducing fracture risk. The project will examine how these agents affect signaling and function in human bone cells.

Direct inquiries can be made by email to: mrybchyn@mail.usyd.edu.au or rebeccam@physiol.usyd.edu.au

ENVIRONMENTAL CONTROL OF PHYSIOLOGY LABORATORY, Medical Foundation Building

Dr Bronwyn McAllan

Animal models are frequently used to understand physiological mechanisms. Comparative Physiologists use the diverse information that can be discovered in a wide variety of non-laboratory animals to help formulate ideas about physiological processes. Current research interests have focused on the environmental control of structure and function in mammals, especially marsupials. Research areas include the photoperiodic control of reproduction, and the seasonal implications for metabolism. Other research relates to the seasonal physiological and endocrinological changes in mammals and their morphological implications. This has involved endocrine influences on non-target physiological systems, such as the renal system. Currently we are developing programmes to look at the interactions between stress, reproduction and ageing, using the small marsupials Antechinus stuartii (brown antechinus) and Sminthopsis macroura (striped-faced dunnart) as animal models.

Project Title: The regulation of reproductive physiology by environmental photoperiod
The regulation of reproductive physiology by environmental photoperiod is poorly known in marsupials. By manipulating photoperiod and measuring reproductive outcomes in Sminthopsis macroura, including detecting hormonal changes by RIA, we can learn more about the control of seasonal reproduction in marsupials.

Project Title: The regulation of reproduction and metabolism by photoperiod and temperature. Seasonal changes in reproduction and torpor use (measured by open flow respirometry) are important for the survival of many small mammals. By exposing the marsupials Sminthopsis macroura and Sminthopsis crassicadata to different photoperiods and temperatures we can understand more about the survival responses of mammals to environmental change.

Project Title: Is Tau protein present in marsupials?

With A/Prof Lars Ittner (Bmri).

Alzheimer’s disease (AD) is typified by significant loss of memory and the sense of smell, and with behavioural changes including aggression and disinhibition. The project will determine whether tau protein (the microtubule associated protein that makes up the neurofibrillary tangles when hyperphosphorylated in AD) is present in the marsupials, Sminthopsis crassicaudata and S. macroura and, if present, whether its presence differs depending on the age of the animal.This may lead to the development of an exciting new animal model for AD.

Direct inquiries can be made by email to: Dr Bronwyn McAllan - bmcallan@physiol.usyd.edu.au

EMBRYONIC STEM CELL LABORATORY, Medical Foundation Building

Dr Michael Morris

mob: 0432 972 361

How do mammalian, including human, embryos grow? And how can stem cells grown in the laboratory shed light on the highly complex mechanisms that control development? My lab focuses on understanding the complex molecular pathways and circuits that control early stages of development – from pluripotency to gastrulation to cells of the developing nervous system. We have discovered a number of simple molecules which, surprisingly, act like growth factors to promote embryo development at various stages.

Embryonic stem (ES) cells have the potential to differentiate into any cell type of the developing embryo and adult. For this reason they have proved invaluable in understanding the molecular mechanisms that drive normal development and can provide a window into what happens during abnormal development. In addition, ES cells have great potential in treating a large number of currently incurable or poorly treatable human diseases and injuries, including neuropathies, brain and spinal injuries, muscular diseases, and diabetes.

Since ES cells recapitulate many of the complex processes that occur during mammalian embryogenesis, this provides enormous experimental advantages because it is possible to identify molecules, signaling pathways, genetic and epigenetic events that contribute to stemness and that direct the differentiation of stem cells to specific cell fates. Thus, we use ES cells as an in vitro model to understand the key molecular mechanisms underpinning critical developmental milestones. We also develop protocols to direct the differentiation of ES cells to specific cell types that can be used in animal models of human disease. In addition, we apply the knowledge we have gained from stem-cell behaviour in vitro to determine if the development of embryos themselves are controlled by the same or similar mechanisms. In particular, we focus on 3 key milestones in development which must be negotiated successfully: formation of the blastocyst, gastrulation, and neurogenesis.

Thus, these projects examine the directed differentiation of mouse ES cells, via a series of embryologically relevant cell types, to multipotent neural progenitor cells that ultimately can be driven to form neurons, glia and neural crest cells that make up the central and peripheral nervous system. Our focus is on the signalling pathways and how those pathways interact to drive this directed differentiation. Techniques to be used in these projects include tissue culture, cell signalling analysis, gene expression analysis, immunohistochemistry and fluorescence microscopy, and flow cytometry.

You are welcome to direct your enquiries to Dr Michael Morris via email (michaelmorris@med.usyd.edu.au) or phone.

Developmental & Cancer Biology Laboratory, Anderson Stuart Bldg, Room N410, Telephone: +61 2 9351 4267

Dr Matt NAYLOR

Research in the Developmental & Cancer Biology Lab focuses on understanding how normal development and cell function is controlled, and then how this regulation is perturbed to result in human disease such as cancer.

Specifically, research in the lab has focused on transcriptional and cell-matrix 'master' regulators of cell fate (eg. whether or not a cell undergoes proliferation or differentiation) in breast and prostate development and cancer. Using whole genome transcript profiling and subsequent mouse and human cell based models, we have identified several novel regulators of normal breast and prostate development and shown that altering the function of these genes can either speed up or slow down cancer progression. We are now exploring the potential diagnostic and therapeutic potential of these novel targets by exploring their functional mechanism and by expanding our studies to human patient cohorts.

As the genes and developmental pathways we work on control cell fate decisions in multiple systems, we are examining the function of these genes in major human diseases such as breast & prostate cancer, bone metastasis, cardiovascular (atherosclerosis), muscle and heart disease.

Project Descriptions:

1) Determine the role of Runx2 in Atherosclerosis. Atherosclerosis is the build up of fatty deposits (plaques) along arterial walls. Eventually these deposits undergo calcification, resulting in blockage and/or hardening of the arteries and the restriction of blood flow resulting in tissue damage or death. Runx2 regulates bone development and recently has also been implicated in the calcification of atherosclerotic plaques (Sun et al., Circulation Res 2012). Using our newly developed floxed mouse models along with siRNA, lentivirus, qPCR, and cell culture based techniques, this project will explore the role of Runx2 in atherosclerosis and the molecular mechanisms through which Runx2 can regulate this process.

2) Investigate the role of Paxillin in breast cancer & metastasis. Breast cancer is the most common invasive cancer of women, with Australian women having a lifetime risk of 1 in 9 for developing the disease. Although prognosis for early or locally contained disease is good, patients diagnosed with metastasis have a long term survival rate of only 5-10%. We have previously shown that Integrins, which regulate the interaction between a cell and its local environment, control normal breast development and cancer progression. The role of paxillin, an integrin adaptor protein in this process remains unknown, but its expression is correlated with aggressive disease and cancer cell migration. This project will explore the role of paxillin in breast cancer cell function, tumourigenesis and metastasis. Techniques employed will include a combination of in vitro based techniques such as cell culture, morphology, migration and proliferation assays, siRNA, and in vivo based approaches such as xenografts.

3) Examine the role of Paxillin in heart & muscle function. Integrin receptors can act as scaffold proteins linking the extracellular matrix to the cells actin cytoskeletal system. Critical roles for integrins and downstream adhesion proteins have been demonstrated in the regulation of heart and muscle function in both mice and zebrafish, and the mutation of some of these proteins results in human muscular dystrophies. Paxillin is a critical component of the integrin adhesion complex but tis role in muscle or heart function is unknown, largely because paxillin knockout mice are embryonic lethal. Using paxillin floxed mice recently developed in our lab, along with cell culture, siRNA, lentivirus, and qPCR based techniques, this project will begin to determine the role of paxillin in heart and muscle cell function.

4) Metabolism and breast cancer. There is a clear link between metabolic disorders and obesity within a variety of different cancer types, including breast cancer. In addition, a key component in the progression of cancer is said to be the ability of a cancer cell to rewire its metabolic pathways to cope with increased energetic and biosynthetic demands required during tumour progression. Using novel inhibitors in cell culture studies along with proliferation assays and mouse based carcinogenesis models, this project will investigate the effects of inhibiting lipogenesis and determine the subsequent effects on breast cancer cell growth and tumourigenesis.

Direct enquiries can be made by email to: Dr Matt Naylor - mnaylor@physiol.usyd.edu.au

MOLECULAR NEUROSCIENCE LABORATORY, Anderson Stuart Bldg, Room N343, Telephone: +61 2 9351 4598

A/Prof Bill Phillips

Project title: Role of the teneurin genes in development and function of the mammalian neuromuscular junction. (co-supervised by Bill Phillips, Cathy Leamey, Atomu Sawatari and Dario Protti)

The teneurins (Ten-Ms) cell-surface adhesion/signalling proteins involved in guiding axons to their correct targets in the developing brain. It has recently been reported that the homologous genes in the fruit fly Drosophila play a role in the development of the neuromuscular junction (NMJ; Mosca et al. 2012). The overall aim of this collaborative project is to determine whether the mammalian teneurin genes also play a role in the development and function of the neuromuscular junction. This has the potential to open up a new avenue of research into how our neuromuscular connections arise.

There are two separate projects:

1) Does knock-out of teneurin genes alter the structure of the developing mouse NMJ and/or motor behavior? This project will involve confocal microscopy of NMJs and some behavioral observations

2) Does knockout of teneurin genes alter neuromuscular transmission and short-term synaptic plasticity? This project will involve intracellular electrical recordings of synaptic potentials from muscle fibres

Ref: Mosca et al. (2012). Trans-synaptic teneurin signalling in neuromuscular synapse organization and target choice. Nature 484, 237-241.

Project title: A new gene potentially causing motor neuron disease? (co-supervised by Bill Phillips and Frank Lovicu)

Motor neuron disease (MND) is a fatal neurodegenerative disease involving the loss of nerve-muscle connections, motor neurons and motor pathways. Several genes have so far been identified as causes of MND in a minority of patients but the full range of causes remain to be determined. This project will characterize a mouse mutant (created serendipitously by random insertion of a transgene) that displays motor behaviour and premature death suggestive of motor neuron disease. We suspect that the insertion of the transgene may have disrupted an endogenous gene that is somehow needed to sustain motor pathways in adult mice. The primary aim of the project will be to use microscopy to find out if there are degenerative changes in the motor centres and/or degeneration of spinal motor neurons and their neuromuscular connections. If this is the case, the second aim will be to identify the disrupted mouse gene through DNA mapping and sequencing. If the disrupted gene is not one that is already associated with MND, future studies will then screen the DNA of families of MND patients for whom no gene has yet been identified.

Project title: Degeneration of the neuromuscular junction as a cause of muscle loss and weakness in old age?

From about 60 years of age the motor system goes into decline. There are declines in the number of connections between motor neurons and muscle fibres and in muscle mass and strength (sarcopenia). Whether the loss of neuromuscular connections is a major cause of sarcopenia remains uncertain. Mice have a lifespan of 2-3 years and our recent work has determined the time-course for the loss of neuromuscular connections in mice with age. We also found that mice permitted voluntary running exercise from middle age retained more of their neuromuscular connections as they got old. The first aim of this project is to use confocal microscopy to determine whether loss of muscle occurs after the loss of its neuromuscular connections and whether sarcopenia can be prevented by voluntary exercise.

The second aim of the project is to investigate the role of the agrin-MuSK-rapsyn system in defending the neuromuscular junction against the ravages of aging. Immunofluorescence microscopy will be used to measure changes in pre- and postsynaptic components of the neuromuscular junctions in mice with age, comparing wild-type mice to mice with only one copy of the gene for either agrin, MuSK or rapsyn. These gene-dosage experiments will tells us how much the aging neuromuscular junction is dependent upon this key synaptic signalling system. Direct enquiries can be made by email to: Bill billp@physiol.usyd.edu.au or phone +61 2 9351 4598 Faxed enquiries can be sent to +61 2 9351-2058

MOLECULAR PHYSIOLOGY LABORATORY

Professor Philip Poronnik

Professor Philip PORONNIK has a long standing interest in the regulation of ion channels, receptors and transporters in the cell membrane. His current research focusses on 2 main areas. One is the regulation of cell transport and signalling by ubiquitin ligases and scaffold proteins, and more recently an interest in the coupling of transporters and substrate regulating proteins. The other is the regulation of renal tubular function and the changes that occur in diabetic nephropathy. This involves understanding the molecular basis of how signalling pathways are altered in disease states. Our group has made significant contributions to the understanding of the roles of the Nedd4 family of ubiquitin ligases and PDZ scaffolds in both epithelial and excitable cells. The laboratory uses a wide variety of techniques including tissue culture, molecular biology, cell imaging and biochemical methods.

Projects currently available:

· Regulation of Ca2+ transport by NHERF PDZ scaffolds and Nedd4 ubiquitin ligases – this project is collaboration with Prof Sharad Kumar at the Centre for Cancer Cell Biology in Adelaide and Prof Peter MacIntyre at RMIT.

· Characterisation of a molecular complex in glia cells involving glutamate transporters and the Na-K ATPase – this project is in collaboration with Prof David Pow at RMIT.

· The epigenetic control of disease: characterization of long noncoding RNAs in a mouse model of diabetic nephropathy – this project is in collaboration with Prof John Mattick (Head of the Garvan Institute) and A/Prof David Nikolic-Paterson at Monash Medical Centre in Melbourne.

For more information please contact me: Philip Poronnik – philip.poronnik@sydney.edu.au

VISION LABORATORY, Anderson Stuart Bldg, Room N659, Telephone: +61 2 9351 3928

Dr Dario Protti

Our research work focuses on the function of the visual system and in particular on the retina. The retina is a light sensitive tissue located at the back of the eye. It consists of an intricate network of neurons, which are critical in the first stage of visual processing and consequently visual perception. The output neurons of the retina are the ganglion cells. They receive excitatory and inhibitory inputs from specific neuronal circuits, whose relative magnitude and timing determine the spatial and temporal properties of the signals that ganglion cells send to higher visual centres in the brain. The relative impact of excitation and inhibition on ganglion cells output, however, is not well understood. Photoreceptor death due to degenerative diseases can lead to blindness and during that process the synaptic connectivity of the retinal networks is altered.

We are currently investigating the physiological and morphological properties of different types of ganglion cells in the normal and diseased eye and the effect of cannabinoids on the visual system.

Projects are currently available in the following areas:

Ganglion cells' morphology and correlation with their physiological properties

Pharmacological modulation by cannabinoids of ganglion cell responses

Effects of cannabinoids on the visual system

Changes in retinal function in animal models of eye disease

Modeling of ganglion cell output using NEURON

The techniques used in these projects are patch-clamp recordings, dynamic-clamp recordings, electroretinogram and confocal microscopy. We also use the modeling environment NEURON to investigate how retinal cells respond to stimuli in different experimental conditions.

Our group consists of senior researchers: Dr Dario Protti, Dr Jin Huang, Dr Stefano Di Marco and a postgraduate student: Terence Middleton.

We also have collaborative projects with other researchers in the Department as well as overseas.

dario.protti@sydney .edu.au

SYSTEMS NEUROSCIENCE LABORATORY, Anderson Stuart Building. Room N121, Telephone: +61 2 9036 7127.

Dr Atomu Sawatari

We are interested in how both environmental and genetic factors can influence the development and function of neural circuits involved in perception and cognition.

The following list provides a summary of some of the Honours projects offered for 2013. For details, please contact me directly. Some of these are offered as collaborative projects with Dr. Catherine Leamey, Dr. Dario Protti, and A/Professor Bill Phillips:

1) Do perineuronal nets (PNNs) define specific circuits within striatal pathways? We have recently shown that only some of the PNNs in the striatum, crucially important in regulating neural plasticity, are associated with parvalbumin positive (PV+) interneurons. The identity of the other cell types ensheathed by these structures is not clear. Projects designed to reveal and characterize these neurons are available.

2) Does Ten_m3 influence the wiring of the neuromuscular junction (NMJ)? Projects that will examine potential alterations in the NMJ of Ten-m3 mice are available (in collaboration with the Leamey, Protti and Phillips labs).

3) Does environmental enrichment affect the development and function of auditory behaviour? Previous work has revealed that mice sing. Projects that explore how stimulating environments affect the development of this important behaviour are available.

4) Can we reverse the maturation of cognitive circuits? Previous work has shown that digestion of PNNs can promote cortical plasticity. Projects that explore how similar treatments affect the functioning of neural structures vital for learning and memory are available.

Direct enquiries can be made by email to: Dr Atomu Sawatari - atomu@medsci.usyd.edu.au

CARDIAC ENERGY METABOLISM LABORATORY. Anderson Stuart Bldg, Room N640. Professor William C. Stanley

Email: wstanley@medicine.umaryland.edu

Prof. Stanley's group studies the role of energy metabolism in the regulation of cardiac structure and function in health and disease. They have worked extensively on how diet and metabolic dysfunction impact the pathophysiology heart failure. Most recently his group has investigated the effects of specific dietary fatty acids on the development and progression of heart failure. Specifically, they investigate the mechanisms for the beneficial effects of marine n3 polyunsaturated fatty acids and other long chain lipids on the structure and function of cardiac mitochondria. Their ultimate goal is to develop new diets to prevent and treat heart failure. The lab uses a wide variety of methods, including mitochondrial isolation and biochemical evaluation, and in vivo assessment of cardiac function using clinically relevant endpoints in rodent models.

Project Title: “Impact of Dietary Fatty Acids on Mitochondrial Pathophysiology and the Progression of Heart Failure”

We recently made the surprising observation that diets that are low in carbohydrate and high in fat are generally beneficial in animal models of heart failure. The finding has clear clinical relevance, and may be applicable to the treatment of heart failure patients. The mechanism for this effect is unclear, and the differential effects of various saturate and unsaturated fatty acids are not clearly understood. Here we will investigate the effects of select dietary fats on the structure and function of mitochondrial membranes in rats with heart failure.

Project Title: “Mitochondrial Proteome Dynamics in Heart Failure Assessed with Heavy Water”.

In this project we will develop a new stable isotope method called “proteome dynamics”. Recent advances by our group in stable isotopic tracer methods and peptide analysis by liquid chromatography-tandem mass spectrometry enables measurement of protein synthesis using deuterium labeled water and assessment of isotopicly labeled amino acid precursors and enriched protein products. Here we will further apply this method to measure the rate of synthesis of muscle proteins in healthy rats and in animals with heart failure. This is a joint project with Dr.T. Kasumov of the Cleveland Clinic Foundation in the USA.

External Honours Projects

The Discipline of Physiology on occasion accepts into its Honours Course students who are performing their research in laboratories outside the Department. The project must be closely allied to physiology and an internal supervisor who is familiar with the area must be prepared to act as the associate supervisor. The student should normally have undertaken at least one 3rd year course in Physiology and must attend the teaching sessions for Honours students which occur weekly within the Discipline.

Supervisors and laboratories which have indicated their interest in taking such students are listed below. You should contact the supervisor of the project directly to express your interest.

o Sensory System and Integration Laboratory – Dr Aaron Camp

o Neuroscience – A/Prof Kay Double

o Visual Development – Dr Alan Freeman

o Diabetes and Islet Biology Group – Anand Hardikar

o Vision Laboratory – Dr Jin Huang

o Alzheimer’s and Parkinson’s Disease Laboratory - A/Prof. Lars Matthias Ittner

o Cardiovascular Neuroscience Laboratory – Dr Jaimie Poloson

Sensory Systems and Integration Laboratory

Supervisor: Dr. Aaron Camp

Title: A question of balance: Ageing of the vestibular sensory epithelium

Airplanes, submarines and even our humble phones use sophisticated guidance systems to allow them to navigate through the environment. Amazingly, vertebrates have used an analogous system for billions of years! This system is called the vestibular or “balance” system. To understand how our vestibular system allows us to maintain balance under normal conditions, how disease impairs this ability, and how balance signals are ultimately combined with those of other senses to enable navigation through our complex world, we need to know how individual cells in the vestibular system process information. Using patch-clamp electrophysiological techniques and two-photon microscopy, you will investigate the sub-cellular signals used by the peripheral vestibular apparatus to detect changes in head and body position. Specifically, you will characterize spontaneous calcium levels, and cellular metabolism (mitochondrial membrane potential) in each type of balance detector (type I and II hair cells) over the mouse life span. This information is crucial to establish a timeline that can be used to pinpoint critical periods in the decline of balance performance with age

Title: A Noisey Nervous system: The impact of synaptic noise on sensory neuron sensitivity.

The output of individual sensory neurons is ultimately dependent on the combination of synaptic inputs and intrinsic neuronal properties. Recent work in our laboratory has shown that even small fluctuations (ones that do not cause either excitation or inhibition) in the membrane potential of sensory relay neurons can produce dramatic changes in their subsequent output. This “synaptic noise” represents the impact of the network activation state within which sensory neurons are embedded, and presumably plays an important role in sensorineural signaling. Using patch-clamp electrophysiological techniques you will investigate the sensitivity of neurons in the central vestibular (balance) pathway. This pathway provides an ideal model since neurons in the vestibular nuclei display a diverse suite of discharge properties, and are known for their capacity to undergo both synaptic and intrinsic “plasticity”. Specifically, you will characterize the gain (sensitivity) of type A, B and C neurons in the Medial Vestibular Nucleus (MVN) to injections of current, and synaptic noise. This information is crucial to understand how individual sensory neurons code information about the outside world.

Title: In the Balance: Central control of peripheral vestibular sensitivity

Much like an iPad, iPhone, or even a submarine, our inner ears contain a sophisticated system designed to detect changes in acceleration and position. This system is called the vestibular (balance) system. The receptors of the vestibular system convert movements of our head and body into signals that can be analysed by the CNS to form an appropriate motor behaviour. Interestingly these receptors (hair cells) also receive a sparse efferent innervation from the brainstem that presumably acts to modulate vestibular signaling. To understand how the vestibular system codes changes in head and body position under normal conditions, and how disease or age impairs this ability, we need to know the role of the efferent vestibular system in signal processing. Using patch-clamp electrophysiological techniques you will investigate the intrinsic membrane properties used by Group E neurons in the mouse brainstem to modulate vestibular hair cell activity. Specifically, you will characterize the discharge and action potential properties of these cells in response to current injection over the mouse life span. This information is crucial to establish the role of the efferent vestibular system in balance function and to produce a timeline that can be used to pinpoint critical periods in the decline of balance performance with age.

AARON CAMP | Lecturer
Discipline of Biomedical Science | School of Medical Sciences | Sydney Medical School
THE UNIVERSITY OF SYDNEY
Office: L226, Cumberland Campus C42 | East St (PO Box 170) Lidcombe | NSW | 1825

Lab: E501, Anderson Stuart Bldg | Camperdown Campus | Camperdown | NSW | 2050
T +61 2 9351 9140 | F +61 2 9351 9520
E aaron.camp@sydney.edu.au

Dr Jin HUANG and Dr Dario PROTTI

Location: Vision Laboratory, Rm N659 Anderson Stuart Bldg, Camperdown

How do we see? To date, our understanding of the mechanisms underlying vision is limited. Located at the back of the eye is the retina. It is light sensitive and contains nerve cells (neurons) that are important in the first stage of visual perception and visual processing.

We aim to find out the properties of the output neurons of the retina. These neurons are called ganglion cells. They receive a variety of excitatory and inhibitory signals within the retina. Hence, their properties depend on how these signals are integrated. The project we are offering examines that balance. We inject excitatory and inhibitory currents into ganglion cells and record their responses to various combinations of excitatory and inhibitory currents. The techniques used in this project are confocal microscopy, whole-cell patch-clamp and dynamic-clamp recordings.

Contact: dario.protti@sydney .edu.au

Assoc Prof Kay Double

Discipline of Biomedical Sciences, School of Medical Sciences, Sydney Medical School, Cumberland Campus

MRI imaging of early neurodegeneration in the brains of “healthy” people

There is much research worldwide into the development of therapies to slow or halt brain cell death in common disorders such as Alzheimer’s disease and Parkinson’s disease. Such approaches will have the most benefit when used as early as possible, optimally even before clinical symptoms develop. Diagnosis of preclinical disease, however, is not yet possible, although brain imaging using techniques such as magnetic resonance imaging (MRI) can detect changes thought to indicate possible preclinical disease. In this project, we are using MRI-based diffusion tensor imaging (DTI) to identify and quantify changes in brain movement circuits in healthy individuals at high risk of developing Parkinson’s disease. Methods in this project include clinical assessment of healthy and Parkinson’s disease subjects, assessment of gross and subtle movement function, functional assessments of motor cortex circuitry, ultrasound imaging of the brain and investigating the structural integrity of brain movement circuits using DTI. All methods for the project are established and subject recruitment is well advanced. Preliminary data suggests that identification of preclinical disease is feasible. The development of preclinical diagnostic methods is likely to lead to significant advances in the treatment of common neurodegenerative disorders. This project is suitable for an Honours or PhD project. Contact Assoc Prof Double (kay.double@sydney.edu.au) for more information.

Development of visual orientation selectivity

Alan Freeman

Discipline of Biomedical Sciences, School of Medical Sciences, Sydney Medical School, Cumberland Campus

Many neurons in primary visual cortex are orientation selective: they respond well to contours of a specific orientation (such as vertical) but poorly to other orientations. Years of laboratory work have shown that this selectivity is at least partly due to the intricate pattern of connections that cortical cells receive from their sub-cortical counterparts. It is not clear, however, how these connections are established duringvisual development. The proposed project will explore this question computationallyby extending an existing mathematical model for signal processing in the visual pathways. A cortical neuron will initially receive inputs from just two sub-cortical cells, one on-centre and the other off-centre, resulting in primitive orientation selectivity. Other sub-cortical cells will then be connected to the cortical neuron but their synapses will only survive if they enhance the orientation selectivity. If the model is correct, this Hebbian process (“cells that fire together wire together”) will yield the highly tuned orientation selectivity seen in real neurons. The student undertaking this project should be mathematically competent. Further, a working knowledge of the software package Matlab will provide a flying start.

Alzheimer’s and Parkinson’s Disease Laboratory

A/Prof. Lars Matthias Ittner. Brain & Mind Research Institute, 9351 0845. lars.ittner@sydney.edu.au

Novel pathomechanisms and therapies in Alzheimer’s disease

Alzheimer’s disease (AD) is the most prevalent neurodegenerative disorder with no cure available. With an aging population, AD is becoming a major health threat worldwide. It is critical to understand what causes neurons to die in the diseased brain, in order to develop novel therapies for AD and related conditions of the aging brain. Here, the research of Lars and his team aims at identifying novel molecular pathomechanisms underlying neurodegeneration, and then translate these findings into new therapeutic approaches. Their cutting-edge research utilizes a wide range of techniques, including latest transgenic mouse models and complementary neuronal cell culture systems, and has been published in top-ranged international journal, such as Cell, PNAS and Nature Reviews Neuroscience.

In the AD brain, there is deposition of two proteins; namely amyloid-b in extracellular plaques and the microtubule-associated protein tau in intracellular tangles. For long tau has been thought to localize exclusively to the neuronal axon, accumulating in other cell compartments only during disease. Challenging this view, we revealed that tau normally also localizes to the dendritic compartment of neurons, functioning as post-synaptic scaffolding protein (Cell, 2010). This new function of tau becomes pivotal in the early phase of disease, mediating the toxic effects of amyloid-b, and hence, providing the first molecular link between the two hallmark proteins in AD. Our finding opened a new direction of research into the functions of tau under physiological conditions and in disease (Nature Reviews Neuroscience, 2011).

Accordingly, the aim of the proposed Honours projects is to reveal novel pathomechanisms involving tau, provide a deeper understanding of the functional relevance of dendritic tau, and decipher the exact molecular interplay between tau and amyloid-b. These studies involve establishing and analysis of new disease mode including the generation of novel transgenic mouse lines in our in-house transgenes facility. Furthermore, a wide range of techniques are available in our laboratory, including molecular gene cloning, biochemical procedures, cell culture, microsurgery and behavioural/motor testing of mice. These methods will assist in analysing complex molecular disease processes and successfully complete a challenging project.

Selected References:

• Ittner LM et al., Dendritic Function of Tau Mediates Amyloid-beta Toxicity in Alzheimer's Disease Mouse Models. (2010) Cell 142:387-397.

• Van Eersel et al., Sodium selenate mitigates tau pathology, neurodegeneration, and functional deficits in Alzheimer's disease models. (2010) PNAS 107:13888-13893.

• Ittner LM et al., Amyloid-beta and tau - a toxic pas de deux in Alzheimer's disease. (2011) Nature Reviews Neuroscience 12:67-72.

• Fath T et al., Primary support cultures of hippocampal and substantia nigra neurons. (2009) Nature Protocols 4:78-85.

• Ittner LM et al., Pronuclear injection for the production of transgenic mice. (2007) Nature Protocols 2:1206-1215.

CARDIOVASCULAR NEUROSCIENCE LABORATORY, Anderson Stuart Bldg, Room N640, Telephone: +61 2 9351 9353

Dr Jaimie POLSON (and Professor Roger A.L. DAMPNEY)

Honours Opportunities in Cardiovascular Neuroscience Research

The Cardiovascular Neuroscience group study the control of blood pressure and sympathetic nerve activity by the brain. The group is headed by Prof Roger Dampney and involves close collaborations with Dr Jaimie Polson, Dr Jouji Horiuchi, and Assoc. Prof Ann Goodchild (The Australian School of Advanced Medicine, Macquarie University). The laboratory uses a wide variety of techniques including recording of blood pressure and nerve activity in the anaesthetized rat, telemetric recording of blood pressure and sympathetic nerve activity in the conscious rat, neuronal tract tracing using retrograde and anterograde tracers and immunohistochemical techniques. We are located on level 6 of the Anderson Stuart building.

In 2013 we are offering three projects, as outlined below.

(1) Project Title: Programmed hypertension: does gestational exposure to high steroid alter the effect of high salt diet on cardiovascular autonomic function?

This project, to be supervised by Dr Jaimie Polson, will focus on how in utero stressors can play a role in the development of hypertension in later life. It is well known that stressors during pregnancy, such as poor nutrition, affect the development of the foetus and predispose the offspring to hypertension and other diseases in later life. This project will use radiotelemetry recording of blood pressure to determine whether the cardiovascular and autonomic nervous system responses to a high salt diet are heightened in offspring that were subjected to raised levels of glucocorticoid during gestation.

No experience is required for this project, and all training is provided. Bring only oodles of enthusiasm and the ability to work hard.

For further information contact Dr Jaimie Polson at jaimie.polson@sydney.edu.au

(2) Project Title: The role of maternal high fat diet on programming of central control of blood pressure.

This project, to be supervised by Dr Jaimie Polson will focus on a high fat diet model of in utero programming. Recent studies have shown in rats that obesity during pregnancy places the offspring at increased risk of cardiovascular disease, including insulin resistance and hypertension. This project will focus whether the offspring of high fat diet dams show signs of altered autonomic function at rest and/or in response to stress that may predispose them to the development of hypertension. The project will use radiotelemetry recording of blood pressure in the conscious rat.

No experience is required for either of these projects, and all training is provided. Bring only lots of enthusiasm and the ability to work hard.

For further information contact Dr Jaimie Polson at jaimie.polson@sydney.edu.au

(3) Project Title: Do the midbrain colliculi play a role in cardio-respiratory responses to auditory-evoked alerting

This project, to be supervised by Dr Jaimie Polson and A/Prof Ann Goodchild will focus on a region within the dorsal midbrain that our laboratory has recently found contains a group of neurons that simultaneously regulate the cardiovascular, respiratory and somatomotor systems, probably in response to “threatening” auditory and visual stimuli. Very little information is available about the output pathways of these neurons in relation to cardiovascular and respiratory control. The aim of this project will be to combine retrograde neuronal tracing from cardiovascular control sites in the brainstem with c-fos immunohistochemistry following a ‘threatening’ high frequency auditory stimulus to determine whether neurons in the collicular nuclei activated by the stimulus project to the cardiovascular control sites.

No experience is required for either of these projects, and all training is provided. Bring only lots of enthusiasm and the ability to work hard.

For further information contact Dr Jaimie Polson at jaimie.polson@sydney.edu.au

(3) Project Title: How fear regulates blood pressure, breathing and temperature

This will be a collaborative project in conjunction with Dr Jaimie Polson and A/Prof Ann Goodchild from the Australian School of Advanced Medicine at Macquarie University, where the project will be conducted. This project will be focused on the amygdala, which plays a critical role in mediating the fear response. Integral to this emotional response are changes in blood pressure. Curiously only blood pressure has been measured but other visceral functions associated with the fear response such as breathing and metabolism have not. The aim of the project is to describe comprehensively the cardiovascular, respiratory and metabolic responses evoked from the amygdala. An integrative physiological approach will be used that will incorporate surgical techniques, pharmacology and electrophysiology. No experience is required and all training is provided. Bring only lots of enthusiasm and the ability to work hard.

For further information contact A/Prof Ann Goodchild at ann.goodchild@mq.edu.au

Diabetes and Islet-biology Group

A/Prof Anand Hardikar

anand.hardikar@ctc.usyd.edu.au

Research in the laboratory is focused on understanding islet biology and development of insulin-producing cells. We work with cadaveric human pancreatic islets as well as biliary duct and gallbladder-derived cells to gather information that would help us understand development of insulin-producing cells. Our previous studies using next generation sequencing of developing human pancreas using the SOLiD platform have provided insight to understanding the role of ncRNAs (specifically microRNAs) in development and differentiation of insulin-producing cells. Present research projects involve applying this information to differentiation of human pancreatic progenitor cells.

In addition to these studies, the lab has 2 other research interests: 1) Understanding the role of microRNAs and non-coding RNAs as biomarkers and regulators of diabetes and its complications. This study involves analysing a large number of patient samples from 5 different clinical trials / studies (RAPID Study: www.RAPIDstudy.info <http://www.RAPIDstudy.info> ) and carrying out specific in vitro and in vivo experiments to understand the biology and function of these microRNAs/ ncRNAs in disease progression. 2) The other interest of the lab is focused on understanding the epigenetic regulation of insulin gene transcription. This involves assessing the transcriptome, epigenome and loopscape (3D chromatin conformation) of insulin-producing cells so as to identify conditions that favour efficient production of insulin. Further details about our research are available through the lab’s website (www.isletbiology.com <http://www.isletbiology.com> ).

1) Understanding the molecular basis of insulin gene expression in human gallbladder epithelial cells

We are the first to demonstrate that human gallbladder epithelial cells transcribe insulin and other pancreatic hormones. This project will attempt to characterize key molecular aspects of these cells and compare their physiological role in glucose-insulin metabolism. Students involved will be trained and supervised in carrying out

a. Cell cultures of gallbladder and pancreatic insulin-producing cells

b. Characterizing cell populations using transcriptome (mRNA and microRNA) and epigenetic (histone methylation) profiling using TaqMan-based quantitative PCR, microfluidics-based low density arrays, chromatin immunoprecipitation and ChIP-sequencing. Single cell characterization using single cell PCR analysis

c. Confocal microscopy and imaging of immunostained and FISH / in situ PCR samples

d. Cell differentiation and functional studies including glucose-stimulated insulin release and potential in vivo function following transplantation into immune-compromised mice.

2) A comparative analysis of multiple cell types committed to endocrine pancreatic lineage:

We and others have demonstrated that cells that transcribe insulin can be found in tissues other than the pancreas. This project will characterize such populations and compare their capacity to transcribe, package and secrete insulin.

Students involved will be trained and supervised in carrying out

a. Cell culture work with human pancreas, gallbladder and other cell types

b. Isolation of endocrine progenitor cells from transgenic (reporter) mice

c. Characterization of cell populations using mRNA and microRNA profiling (TaqMan-based quantitative PCR and microfluidics-based low density arrays), Single cell PCR analysis and analysis of next generation sequencing data

d. Confocal microscopy, flow cytometry, ELISAs and insulin secretion assays