What limits CO2 diffusion inside leaves? Dissecting the diffusion path with Arabidopsis mutants. Human induced increase in atmospheric carbon dioxide is now generally accepted as contributing to global warming. Forecasting our future impact relies on models of terrestrial photosynthesis which use a signature in the atmosphere created by plants when they discriminate against the heavy stable isotope of carbon during photosynthesis. Discrimination between isotopes is affected by carbon dioxide dif ....What limits CO2 diffusion inside leaves? Dissecting the diffusion path with Arabidopsis mutants. Human induced increase in atmospheric carbon dioxide is now generally accepted as contributing to global warming. Forecasting our future impact relies on models of terrestrial photosynthesis which use a signature in the atmosphere created by plants when they discriminate against the heavy stable isotope of carbon during photosynthesis. Discrimination between isotopes is affected by carbon dioxide diffusion within leaves and key steps in this process will be identified through the use of Arabidopsis mutants. Better representation of this process in models will improve estimates of terrestrial photosynthesis and climate change forecastsRead moreRead less
Molecular and Cellular Characterisations of the Cortical Actin Cytoskeleton in the Plant Arabidopsis thaliana. Plant cells contain extensive arrays of the cytoskeletal protein actin that attach to the plasma membrane and may play important roles in cell elongation through interactions with cortical microtubules. However, the organisation, dynamics and functions of cortical actin remain poorly understood. I will combine cell and molecular approaches to understanding cortical actin in living tissu ....Molecular and Cellular Characterisations of the Cortical Actin Cytoskeleton in the Plant Arabidopsis thaliana. Plant cells contain extensive arrays of the cytoskeletal protein actin that attach to the plasma membrane and may play important roles in cell elongation through interactions with cortical microtubules. However, the organisation, dynamics and functions of cortical actin remain poorly understood. I will combine cell and molecular approaches to understanding cortical actin in living tissue of Arabidopsis, using both wild-type and previously uncharacterised mutants, and will develop a novel mutational screening strategy to isolate mutants disrupted in plasma membrane or microtubule binding. This research will contribute significantly to a greater understanding of how the plant grows and develops.Read moreRead less
Disorder as a novel determinant of photosynthetic structure and function: an experimental study. Australia enjoys a world reputation in photosynthesis research, typified by hosting the 2001 International Photosynthesis Congress. It also has a claim to fame for theoretical work in non-equilibrium thermodynamics concerning production of disorder or entropy, yielding new insights into planetary climates. This experimental project investigates the novel relation between entropy/entropy production ....Disorder as a novel determinant of photosynthetic structure and function: an experimental study. Australia enjoys a world reputation in photosynthesis research, typified by hosting the 2001 International Photosynthesis Congress. It also has a claim to fame for theoretical work in non-equilibrium thermodynamics concerning production of disorder or entropy, yielding new insights into planetary climates. This experimental project investigates the novel relation between entropy/entropy production and the structure/function of the solar powerhouse of plants (chloroplasts), and addresses fundamental questions at the interface of biology and physics. The research explores chloroplasts as a manifestation of the all-pervading Second Law of Thermodynamics, advancing Australia's contribution to basic science and helping to train researchers.Read moreRead less
Improving plant reproductive success under heat stress: A sweet approach. This project aims to determine how genetic manipulation of cell wall invertase (CWIN) activity could regulate pollen germination, elongation and fruit set under heat stress using tomato as a model. Plant reproductive processes are highly susceptible to heat stress, which often leads to pollination failure and fruit and seed abortion, hence irreversible yield loss. Research has established that CWIN-mediated sugar metabolis ....Improving plant reproductive success under heat stress: A sweet approach. This project aims to determine how genetic manipulation of cell wall invertase (CWIN) activity could regulate pollen germination, elongation and fruit set under heat stress using tomato as a model. Plant reproductive processes are highly susceptible to heat stress, which often leads to pollination failure and fruit and seed abortion, hence irreversible yield loss. Research has established that CWIN-mediated sugar metabolism and signaling may play crucial roles in pollen growth and fruit set under heat stress. The intended outcome is the generation of critical knowledge that will advance understanding on reproductive development under heat stress, thereby providing significant benefits, such as novel ideas and solutions for improving crop yield.Read moreRead less
Molecular analysis of photosynthetically-linked, active CO2 uptake and CO2 signal transduction by cyanobacteria (blue-green algae). Cyanobacteria (blue-green algae) have evolved a very efficient means of capturing and concentrating CO2 for photosynthetic fixation into sugars, the basic building blocks for cell growth. This process is dependent on the operation of several unique, active uptake systems for CO2 and HCO3-, with their genetic expression regulated by CO2 supply. This proposal will cap ....Molecular analysis of photosynthetically-linked, active CO2 uptake and CO2 signal transduction by cyanobacteria (blue-green algae). Cyanobacteria (blue-green algae) have evolved a very efficient means of capturing and concentrating CO2 for photosynthetic fixation into sugars, the basic building blocks for cell growth. This process is dependent on the operation of several unique, active uptake systems for CO2 and HCO3-, with their genetic expression regulated by CO2 supply. This proposal will capitalize on our progress in describing the functional genetics of this process and aims to elucidate the mechanism of active CO2 uptake and the way that cells sense the ambient CO2 concentration. The information gained is likely to be useful for designing improved crops.Read moreRead less
Functional characterisation of the necrotrophic effector proteins Tox1 and Tox3 from the wheat pathogen Stagonospora nodorum. Fungal pathogens cost the Australian agricultural industry over one billion dollars per year. This project will build upon recent key advances to provide a fundamental basis on how fungal pathogens cause disease. The results from this study will promote future advances in disease management with the aim of securing Australian wheat supplies.
Oxygen isotope discrimination during C4 photosynthesis. Plants with the C4 photosynthetic pathway, like sugarcane and pasture grasses, are vital to Australian agriculture and natural ecosystems. This project will use novel laser spectroscopy to measure oxygen isotope discrimination during photosynthesis and quantify the influence of C4 plants on isotopic signatures of atmospheric CO2.
Photosynthetically active bicarbonate transporters from cyanobacteria & their rational redesign for application in engineered crops that use less water. Marine blue-green algae are critical components of global primary productivity and fisheries productivity but CO2 acquisition processes in these organisms are poorly understood. Our aim is to determine the protein structure and regulatory controls present in two classes of cyanobacterial bicarbonate transporters that are required for efficient p ....Photosynthetically active bicarbonate transporters from cyanobacteria & their rational redesign for application in engineered crops that use less water. Marine blue-green algae are critical components of global primary productivity and fisheries productivity but CO2 acquisition processes in these organisms are poorly understood. Our aim is to determine the protein structure and regulatory controls present in two classes of cyanobacterial bicarbonate transporters that are required for efficient photosynthesis. This information is now critical to the our goal of redesigning these bicarbonate transporters so they will be functional in plants, thereby contributing to the applied objective of engineering crop plants that could produce good grain yields with reduced water requirements.Read moreRead less
Oxygen-18 in water, carbon dioxide, and organic matter: a tool for linking plant biological processes, hydrology and climate change. The globe is warming but pan evaporation is decreasing, because the world is dimming. We do not understand why. Stable, naturally occurring oxygen isotopes in plants (for example, tree rings) and in the carbon dioxide of the atmosphere vary and record climatic changes and physiological responses. Bringing these disparate areas of research together will help us to i ....Oxygen-18 in water, carbon dioxide, and organic matter: a tool for linking plant biological processes, hydrology and climate change. The globe is warming but pan evaporation is decreasing, because the world is dimming. We do not understand why. Stable, naturally occurring oxygen isotopes in plants (for example, tree rings) and in the carbon dioxide of the atmosphere vary and record climatic changes and physiological responses. Bringing these disparate areas of research together will help us to interpret the changes and responses. Such information is needed for planning future water requirements in Australia (agriculture, natural ecosystems, dams) and around the world. The isotopic composition of tree rings and of the atmospheric carbon dioxide is affected by that in water of leaves, and the processes linking them will be studied in detail. Read moreRead less