Unsaturation of vapour pressure inside leaves: fundamental, but unknown. This project aims to determine when and to what extent the air inside leaves becomes unsaturated with water vapour. All current interpretation and modelling of leaf gas exchange assumes saturation under all circumstances. Compelling evidence has been obtained that suggests this is not true under moderate air vapour pressure deficits. A novel technique will be employed to assess the water vapour concentration of the air insi ....Unsaturation of vapour pressure inside leaves: fundamental, but unknown. This project aims to determine when and to what extent the air inside leaves becomes unsaturated with water vapour. All current interpretation and modelling of leaf gas exchange assumes saturation under all circumstances. Compelling evidence has been obtained that suggests this is not true under moderate air vapour pressure deficits. A novel technique will be employed to assess the water vapour concentration of the air inside leaves based on stable isotope analysis of carbon dioxide and water vapour exchanged between leaves and air. The project is expected to provide fundamental knowledge about how stomata regulate photosynthesis and water use, with significant implications for modelling vegetation function and for improving the performance of crop plants.Read moreRead less
Will stomatal responses to humidity and carbon dioxide constrain tropical forest productivity as atmospheric carbon dioxide rises? This project will investigate two physiological processes that will partly determine growth responses of tropical forest trees to rising atmospheric carbon dioxide. The project will produce equations summarising physiological responses that can be incorporated into process-based models of tropical forest productivity.
Microenvironments which support extramedullary hematopoiesis. Tissue regeneration is a breakthrough technology absolutely dependent on knowledge of the stem cells and stromal cells which support differentiation and tissue development. This project investigates the stromal cell types in spleen which can regenerate blood-forming cells in an ectopic tissue site or artificial matrix.
Linking phytoplankton to fisheries using zooplankton size spectra. This project aims to develop innovative numerical methods to understand the dynamics, carbon export, and trophic structure of zooplankton. The trophic links between phytoplankton, zooplankton and fisheries are unknown. The size- frequency distribution of zooplankton (size spectrum) is an innovative method for estimating their growth, predation and production as food for fish. Analysis of a global synthesis of zooplankton size dis ....Linking phytoplankton to fisheries using zooplankton size spectra. This project aims to develop innovative numerical methods to understand the dynamics, carbon export, and trophic structure of zooplankton. The trophic links between phytoplankton, zooplankton and fisheries are unknown. The size- frequency distribution of zooplankton (size spectrum) is an innovative method for estimating their growth, predation and production as food for fish. Analysis of a global synthesis of zooplankton size distributions from tropical to polar environments are expected to reveal these vital rates of pelagic ecosystems. The zooplankton rates will reveal, for the first time, the link between phytoplankton and fisheries, and will significantly improve ecosystem models and global assessments of environmental change.Read moreRead less
Hydraulic control on water use, growth and survival in tropical rainforest. This project aims to measure drought-related limits to water transport in the woody xylem tissue of trees in Australian tropical rainforests, to understand how this influences tree water use, photosynthesis, health and mortality risk. Tropical rainforests are sensitive to climate variability, especially drought, but this sensitivity is poorly understood, despite large effects regionally and globally. This project will co ....Hydraulic control on water use, growth and survival in tropical rainforest. This project aims to measure drought-related limits to water transport in the woody xylem tissue of trees in Australian tropical rainforests, to understand how this influences tree water use, photosynthesis, health and mortality risk. Tropical rainforests are sensitive to climate variability, especially drought, but this sensitivity is poorly understood, despite large effects regionally and globally. This project will compare forests that contrast strongly in seasonal drought stress, and use the information to develop a model designed for species-diverse forest, with subsequent potential global application. The understanding gained will enable widely applicable advances designed to feed through rapidly to regional- and global-scale models that inform land use, economic and social policy-making.Read moreRead less
Gain from pain: new tools from venomous animals for exploring pain pathways. This project aims to explore animal venoms for new pain-causing toxins, to determine their structure and mechanism of action. Many venomous animals use their venom defensively and envenomation is frequently associated with rapid and often excruciating pain. In most cases the molecular mechanisms by which they achieve this is unknown. Using biochemical, pharmacological and biophysical techniques, this project expects to ....Gain from pain: new tools from venomous animals for exploring pain pathways. This project aims to explore animal venoms for new pain-causing toxins, to determine their structure and mechanism of action. Many venomous animals use their venom defensively and envenomation is frequently associated with rapid and often excruciating pain. In most cases the molecular mechanisms by which they achieve this is unknown. Using biochemical, pharmacological and biophysical techniques, this project expects to uncover toxins that employ new mechanisms of pain signalling, leading to new insights into pain physiology.Read moreRead less
Molecular mechanisms of signalling by plant immune receptors. This project aims to understand how resistance proteins function and to find new sources of these proteins. Plant diseases account for 15% loss of global crop production, representing a threat to food security. Fungicides, one key form of protection, represent environmental concerns. The other key form of protection corresponds to resistance gene breeding, which is limited by lengthy breeding processes, restricted choice of genes from ....Molecular mechanisms of signalling by plant immune receptors. This project aims to understand how resistance proteins function and to find new sources of these proteins. Plant diseases account for 15% loss of global crop production, representing a threat to food security. Fungicides, one key form of protection, represent environmental concerns. The other key form of protection corresponds to resistance gene breeding, which is limited by lengthy breeding processes, restricted choice of genes from sexually compatible species and short effective time spans in the field. Building on previous research, this project aims to characterise the molecular basis of the Toll/interleukin-1 receptor domain-mediated nicotinamide adenine dinucleotide (NAD+) cleavage and the structural architecture of plant NLR complexes. This knowledge will support the long-term objective of protecting crops from pathogens.Read moreRead less
Understanding the molecular function of plant disease resistance proteins, pathogen effectors and their interaction to protect Australian agriculture. This project aims to understand the processes that enable resistant plants to detect and respond to pathogen attack. The acquired knowledge will form the foundation for durable plant disease resistance measures that can be applied to a wide range of crop diseases in an environmentally sustainable manner.
Structural basis of plant immune receptor signaling. Plants detect invading pathogens and trigger immune responses in a process called “effector-triggered immunity”, in which pathogen effector (avirulence) proteins are recognized by plant resistance proteins, typically so-called “plant NLRs”. Ongoing work in the applicants’ laboratories has shown that oligomerization into “resistosomes” and NAD+ (nicotinamide adenine dinucleotide) cleavage play central roles in the process. Building on these dat ....Structural basis of plant immune receptor signaling. Plants detect invading pathogens and trigger immune responses in a process called “effector-triggered immunity”, in which pathogen effector (avirulence) proteins are recognized by plant resistance proteins, typically so-called “plant NLRs”. Ongoing work in the applicants’ laboratories has shown that oligomerization into “resistosomes” and NAD+ (nicotinamide adenine dinucleotide) cleavage play central roles in the process. Building on these data, the project aims to characterize the structures of the signaling molecules resulting from TIR (Toll/interleukin-1 receptor) domain-mediated NAD+ cleavage and the structural architecture of plant NLR resistosomes. This knowledge will support the long-term objective of protecting crops from pathogens.Read moreRead less
Directed evolution of enzymes for bioremediation: structure function studies of bimetalloenzymes. We will evolve enzymes that degrade organophosphate pesticides (OPs) that are used in Australian agriculture. Although these OPs were designed to kill insects they are closely related to chemical warfare agents and are known to be toxic to humans. Bacteria have acquired a number of enzymes that degrade some OPs. One such enzyme has been used in field trials demonstrating its potential to degrade OP ....Directed evolution of enzymes for bioremediation: structure function studies of bimetalloenzymes. We will evolve enzymes that degrade organophosphate pesticides (OPs) that are used in Australian agriculture. Although these OPs were designed to kill insects they are closely related to chemical warfare agents and are known to be toxic to humans. Bacteria have acquired a number of enzymes that degrade some OPs. One such enzyme has been used in field trials demonstrating its potential to degrade OP residues. However, many pesticides are not removed rapidly and OP-degrading enzymes require modification(s) if they are to be useful environmental reagents - this can be achieved with directed evolution. Read moreRead less