Plant Molecular Genetics and Developmental Biology
Investigating plant diversity and evolution
Plant leaves show a wonderful diversity in shape, size and colour, with variations that enrich the beauty of our environment. Our research investigates leaf shape diversity and evolution, and how leaf shape influences plant responses to the environment.
Plant leaves are factories that support life on our planet. Through the process of photosynthesis leaves harvest energy from sunlight and produce the air we breathe and the food we eat. Leaves occur in an enormous variety of shapes. We are studying the genetics behind leaf shape variation. Our focus is on the function of a group of homeobox transcription factor genes and their special role in determining leaf shape.
We work with two plant species; Arabidopsis thaliana has subtle patterns of growth at the leaf margin of a simple leaf whereas the closely related Cardamine hirsuta has a more extreme pattern of growth at the leaf margin creating a more complex shape or compound leaf. Comparing and contrasting two related species helps us understand ways in which leaves evolve diversity in shape. Our research combines the power of genetics, molecular biology, cell and developmental biology to understand fundamental processes in plant growth.
The pattern of growth at the margin or edge of a leaf results in features such as serrations or teeth that are a defining characteristic of a species. Arabidopsis thaliana has a simple leaf shape with margin serrations. Multiple homeobox transcription factor genes control the growth of these serrations. This project aims to understand the interactions between these homeobox genes and how their expression domains converge to effect leaf margin growth. This work uses cutting-edge gene editing techniques to probe gene function, gene expression patterns and gene regulatory interactions.
Cardamine hirsuta is a close relative of Arabidopsis thaliana, but this species has compound leaves, where the leaf is divided into multiple leaflets. This project builds on our research with Arabidopsis thaliana and aims to establish conservation or divergence of homeobox gene function in the two related species. The project uses cutting-edge gene editing techniques to probe gene function, gene expression patterns and gene regulatory interactions.
Leaf shape variation in different plant species is to some extent correlated with environmental conditions with less lobed leaves associated with warmer and wetter environments. This project aims to determine whether changes in leaf shape resulting from altered homeobox gene function impacts on plant growth and response to the environment. The project uses a combination of genetics, biochemistry and plant physiology to address the relationship between leaf shape and plant productivity.
For information about opportunities to work or collaborate with the Plant Molecular Genetics and Developmental Biology group, please contact Associate Professor Mary Byrne at mary.byrne@sydney.edu.au
