Neurobiology Laboratory
Professor Garth Nicholson
The Neurobiology Laboratory, headed by Professor Garth Nicholson, is an internationally prominent research group in the field of neurogenetics. The group comprises of a clinical department in the hospital where patients and their families are investigated and blood samples are obtained to perform molecular genetic research to be conducted within the ANZAC Research Institute. The group’s neurogenetic research focuses on the search for genes for various neurodegenerative diseases, particularly those which if defective cause forms of peripheral nerve and motor neuron disease. The research group has mapped the genes for three new hereditary neuropathies in the last few years. These discoveries provide the basis for ongoing research within the laboratory. Another area of research in the Neurobiology group is determining the function of the genes found in these neuro-degenerative diseases. This research looks at how the mutant proteins are trafficked throughout the cell; expression and activity of the protein; where the mutant protein is localized in the cell; and how cell-signaling events are altered due to these proteins this information will allow us to investigate possible drug targets for these diseases. The research projects below will provide opportunities for both PhD and Honours students to find genes and then determining the functional significance of the mutations identified in the families being studied. These projects cover a range of contemporary molecular biological and cellular biological procedures.
Project 1: Construction and characterisation of a transcript map for dominant intermediate Charcot-Marie-Tooth neuropathy (CMTDI1) on chromosome 19p12-p13.2.
The goal of this project is to characterize a transcript map of chromosome 19p12-p13.2 where CMTDI1 has been localized using genetic linkage studies. The region of DNA containing the defective CMTDI1 gene has been refined to a 2.5 megabase region. A total of 57 known genes map within this interval. Projects will be planned to characterize transcripts that have been predicted from genomic sequence by computer programs but not verified through experimental work. Some of the transcripts represent only partial coding sequence so projects will be planned to identify full length clones using 5’ and 3’ rapid amplification of cDNA ends (RACE). As part of the mutation screening program transcripts will need to be prioritized based on their expression in relevant neural tissues. All projects will provide experience in obtaining information from the human genome project and accessing information regarding tissue expression, gene structure, genes sequence and comparative genomics. Candidates who enroll in this project will gain invaluable experience in molecular biology techniques and bioinformatics.
Contact: Dr Marina Kennerson
Tel: +612 9767 9119
Email:
Dr Danqing Zhu
Ph: +612 9767 9104
Email:
Professor Garth Nicholson
Ph: + 612 9767 6796
Email:
Project 2: Genetic linkage studies in pyramidal Charcot-Marie-Tooth neuropathy.
The aim of this project is to map the gene locus for pyramidal Charcot-Marie-Tooth neuropathy using genetic linkage studies. Once a gene locus is identified projects will be planned to further refine the region of by screening additional families with similar phenotypes to see if they map to the same locus. Individuals working on this project will gain experience in microsatellite analysis for genotyping individuals and extended haplotype analysis. Potential positional candidate genes will be screened for mutations if they are expressed in relevant neural tissues and have any possible functional relevance to the disorder. Projects will be planned to assist in refining the region to a physical distance of DNA that is amenable to positional cloning strategies. All projects will provide experience in obtaining information from the human genome project and accessing information regarding tissue expression, gene structure, genes sequence and comparative genomics. Candidates who enroll in this project will gain invaluable experience in molecular biology techniques and bioinformatics.
Contact: Dr Marina Kennerson
Tel: +612 9767 9119
Email:
Dr Danqing Zhu
Ph: +612 9767 9104
Email:
Professor Garth Nicholson
Ph: + 612 9767 6796
Email:
Relevant publications:
- Kennerson et al. (2001) Am J Hum Genet 69(4):883-8. [PMID: 11533912]
- Zhu et al. (2003) Neurogenetics 4:179-183 [PMID: 12761657]
- Vucic et al. (2003) Neurology 60:696-9. [PMID: 12601114]
Project 3: The localization and expression of the protein SPTLC1 in dorsal root ganglia cells during hypoxia.
Serine palmitoyltransferase (SPT) is a pyridoxal 5’- phosphate dependent enzyme that catalyses the first step of biosynthesis of sphingolipids, including ceramide and sphingomyelin (Snell et al, 1970; Medlock et al, 1988). Sphingolipids are known to be important second messengers in various cellular events including proliferation, differentiation, senescence, apoptosis and immune response (Linn et al, 2001). SPT is thought to be a rate-determining enzyme in the sphingolipid synthetic pathway and therefore a key enzyme that regulates cellular sphingolipid content. For mammals and yeast, two gene products (SPTLC1 and SPTLC2) are necessary for sphingolipid synthesis and appear to be physically associated. However, little is known about the structure of the enzyme due to its membrane association.
Previously, researchers in our laboratory identified 3 different mutations (independently confirmed by R.H. Brown in US families) in subunit 1 of the serine palmitoyl transferase (Dawkins et al. 2001). This result was unexpected, as we had initially thought this an unlikely candidate: as it is an enzyme with a housekeeping function, unlike most other neurodegenerations, that have proven to be associated with protein accumulation (Kopito 2000). The 3 single base mutations make 2 non-conservative changes in amino acids (Cys to Tyr and Val to Asp), presumably resulting in conformational changes in subunit one of the SPT protein.
This project aims to define the localization and expression of SPTLC1 in dorsal root ganglia cells during hypoxic insult. This will be carried out using dorsal root ganglia cells synchronized in various phases of the cell cycle. The latest molecular and cellular biological techniques will be used in this project, for example, confocal microscopy, flow cytometry, cell culture, RT-PCR, Western blotting and 2-dimensional gel electrophoresis.
Contact:Dr Simon Myers
Tel: +612 9767 9104 / 9767 9100
Email: smyers@anzac.edu.au
Professor Garth Nicholson
Ph: + 612 9767 6796
Email: