Plant Molecular Genetics and Developmental Biology Lab

Our aims

Developmental biology aims to understand how a single cell generated from fertilization of an egg cell with a sperm gives rise to a complex multicelluar organism. This amazing process is controlled by genes and gene interaction networks, which turn on or turning off in different tissues and at different times.

We study some of these gene networks and how they affect development, focusing on plant shoot development and plant fertility.

In our lab we use a number of approaches for our research including genetics, molecular biology, cell biology, and functional genomics. 

Our research

In our lab we use a number of approaches for our research including genetics, molecular biology, cell biology, and functional genomics. 

Genes that control plant shoot meristem function and leaf development

Plant shoot and root meristems are indeterminate structures that are established during embryogenesis. Ultimately these two structures give rise to the entire body of the plant. The shoot meristem has two functions. A population of undifferentiated stem cells are required to maintain the meristem for further growth. Cells derived from this stem cell population are recruited to form differentiated structures of the plant such as leaves.

Gene networks are involved in maintaining the difference between stem cells of the meristem and differentiated cells of lateral organs. Through the use of forward and reverse genetics we have identified key components of this network including transcription factors, post-transcriptional silencing (RNAi) genes and genes encoding ribosomal proteins.

Our research is continuing to investigate the function of ribosomal protein and RNAi genes in plant development.

Plant Fertility

The germline cells of plants differentiate in reproductive structures (gametophytes), which develop in the adult stage of plant growth. The female gametophyte is initiated as a germline cell that is surrounded by non-reproductive somatic cells. The germline cell undergoes meiosis and one of the resulting haploid daughter cells undergoes mitotic divisions to form a multicellular gametophyte.

Ribosomal proteins are required at different points in this developmental process. Reduction in the dose of some ribosomal proteins leads to disruption of mitotic cell divisions, differentiation of the embryo sac, or changes in growth of the somatic tissues surrounding the embryo sac depending on the dose of the ribosomal protein.

Our research aims to understand how the dose of select ribosomal proteins determines cell divisions and growth essential for fertility.

Plant embryogenesis

Plants start life as a single cell resulting from fertilization. In Arabidopsis, this single cell undergoes an initial set of stereotypical cell divisions. The first cell division results in a large basal cell and a small apical cell. The apical cell undergoes divisions progressing through two, four, eight, sixteen-cell stages of embryo development.

At the 16-cell stage the embryo forms a small globular structure. Further cell divisions set up a pattern of tissue and organ types including the shoot and root meristems, and the embryonic leaves or cotyledons. Mutations in some ribosomal protein genes are embryo lethal. Interestingly these ribosomal protein deficient embryos initiate embryogenesis and cease growth specifically at the globular stage of development.

Our research aims to understand why the globular stage of embryo development is sensitive to the level of ribosomal proteins.

Our people

• Associate Professor Mary Byrne

Current Lab Members

• Dr Sue Firth (Research Associate)
• Debbie Devis (Honours student)

Opportunities

For information about opportunities to work or collaborate with this group, contact Associate Professor Mary Byrne via Research Supervisor Connect.