biological sciences HONOURs 2014 - The University of Sydney

36 PLANT CELL BIOLOGY
Research Interests
My research in plant cell biology focuses on the plant
cytoskeleton and plasmodesmata, the channels responsible
for intercellular communication. Plasmodesmata transport
water, minerals, metabolites, transcription factors and RNAs
throughout plants. We are trying to understand the details of
transport through plasmodesmata, what molecular interactions
are involved, how is it regulated, what pathway it takes
and how viral “movement proteins” modify it. We use highresolution
microscopy, immuno-cytochemistry, expression of
fluorescently tagged proteins and micro-injection.
The plant cytoskeleton is involved in targeting and transport
of components within cells, cell division and directing cell wall
deposition to generate plant cell shape. We are studying the
role of the cytoskeleton in intercellular transport and in the
generation of plant cell shape, such as in the jig-saw shaped
“pavement” cells found in the epidermis of some leaves.
Honours projects
I develop a project topic in collaboration with potential Honours
student so that it can be tailored to their particular strengths
and interests. Please feel free to contact me for a chat.
Professor Robyn
Overall
Room 510, Carslaw
Building F07
T: (02) 9351 2848
E: robyn.overall@sydney.
edu.au
1. Building a functional model of plasmodesma macro-molecular architecture. This project
aims to develop a 3D model of the structure of plasmodesmata with the molecular identity of
the structures identified. To generate an accurate image of the structure, the project will use
electron tomography of material prepared by high-pressure freeze-substitution.
2. Modification of plasmodesmata by viruses. Plant viruses hijack plasmodesmata to move
throughout the plant. In collaboration with Peter Waterhouse’s lab, we have recently identified
a marker for the precise timing of the very first entrance of the virus into uninfected cells.
This project aims to exploit this indicator to identify if the virus modifies the structure of
plasmodesmata as it moves through them. It will image live tissue in which the invading virus
and this indicator are fluorescently tagged and electron microscopy to see if there are changes
in structure at high resolution.
3. High-resolution imaging of the cytoskeleton and cell wall in pavement cells. Microtubules,
a component of the cytoskeleton, play an important role in the development of the complex
jigsaw shape of pavement cells. This project will use high resolution scanning electron
microscopy to investigate the microtubules by imaging the orientation of the most recently
deposited cellulose microfibrils in these pavement cells and to determine the effect of disrupting
the microtubules on the microfibril orientation and plant cell shape.