LATERAL GENE TRANSFER, GENOME EVOLUTION AND THE EMERGENCE OF NEW DISEASES CAUSED BY FUNGAL PATHOGENS IN THE PLEOSPORALES. Normal evolution involves the transfer of genes within species. The modest variation between progeny powers natural selection. Lateral gene transfer is the movement of genetic material between species. It allows for large evolutionary steps. Although common in bacteria, it has rarely been described convincingly in higher organisms such as fungi, plants or animals. We have evi ....LATERAL GENE TRANSFER, GENOME EVOLUTION AND THE EMERGENCE OF NEW DISEASES CAUSED BY FUNGAL PATHOGENS IN THE PLEOSPORALES. Normal evolution involves the transfer of genes within species. The modest variation between progeny powers natural selection. Lateral gene transfer is the movement of genetic material between species. It allows for large evolutionary steps. Although common in bacteria, it has rarely been described convincingly in higher organisms such as fungi, plants or animals. We have evidence that one group of fungal pathogens is particularly adept at acquiring new genes that enable them to cause new diseases. We will determine the mechanism and frequency of gene transfer in this group. The work had fundamental significance in evolutionary biology, in the emergence of new diseases and in the use of genetically-modified organisms.Read moreRead less
How common and what is the significance of cis-acting regulatory variation and genomic imprinting in plants? Plant based processes provide truly sustainable solutions to many of the challenges facing Australia. The proposed research will help elucidate how plants regulate variation in gene expression rather than changes in the structure of encoded proteins. This is an area of gene expression, that has not been approached before, that explains the plant's ability to respond to external stimuli. ....How common and what is the significance of cis-acting regulatory variation and genomic imprinting in plants? Plant based processes provide truly sustainable solutions to many of the challenges facing Australia. The proposed research will help elucidate how plants regulate variation in gene expression rather than changes in the structure of encoded proteins. This is an area of gene expression, that has not been approached before, that explains the plant's ability to respond to external stimuli. Variation between plant species in the number of genes does not fully explain the differences between them. This information will come not from seqenceing genomes but from investigation of regulatory elements. Read moreRead less
The genetic and molecular organisation of the self incompatibility gene region in the grasses. Self-incompatibility (SI) is a cell-cell recognition process used by plants to prevent self-pollination and force outcrossing. It is widespread, occurring in a third of plant families. Although studies of SI go back to the 1800s, the origin of SI remains a mystery. Recent advances in the molecular characterisation of SI loci in some species has re-ignited debate on its origins but has provided few answ ....The genetic and molecular organisation of the self incompatibility gene region in the grasses. Self-incompatibility (SI) is a cell-cell recognition process used by plants to prevent self-pollination and force outcrossing. It is widespread, occurring in a third of plant families. Although studies of SI go back to the 1800s, the origin of SI remains a mystery. Recent advances in the molecular characterisation of SI loci in some species has re-ignited debate on its origins but has provided few answers. This project uses the grasses to explore the origins of SI. As a model system, the grasses offer detailed genetic and molecular data and aspects of floral architecture associated with SI can be investigatedRead moreRead less
Molecular mechanisms of catalysis and the basis of substrate specificity in polysaccharide hydrolases. Reaction intermediates along hydrolytic pathways and molecular determinants of substrate specificity of barley B-glucan exo- and endohydrolases will be defined using crystallographic and kinetic analyses. These enzymes are of central importance in cell wall metabolism during development of higher plants, and in plant-pathogen interactions. Realization of the project objectives will not only pro ....Molecular mechanisms of catalysis and the basis of substrate specificity in polysaccharide hydrolases. Reaction intermediates along hydrolytic pathways and molecular determinants of substrate specificity of barley B-glucan exo- and endohydrolases will be defined using crystallographic and kinetic analyses. These enzymes are of central importance in cell wall metabolism during development of higher plants, and in plant-pathogen interactions. Realization of the project objectives will not only provide fundamental information on catalytic mechanisms, but will also provide opportunities to manipulate enzyme specificity. Further, site-directed mutagenesis of the enzymes will be used to generate glycosynthases, which will be evaluated for their ability to synthesise novel oligosaccharide and polysaccharide products, some of which might show immunomodulating activity.Read moreRead less
Determining how the soluble dietary fibre beta-glucan is made in cereals. This Project aims to define the molecular mechanisms that control the processes involved in the biosynthesis and regulation of mixed linkage glucan, a major soluble dietary fibre in the cell walls of cereal grains. Plant cell walls determine the quality of most plant-based products used in modern human societies, yet the regulatory mechanisms responsible for their modulation are not well understood. Key distinguishing feat ....Determining how the soluble dietary fibre beta-glucan is made in cereals. This Project aims to define the molecular mechanisms that control the processes involved in the biosynthesis and regulation of mixed linkage glucan, a major soluble dietary fibre in the cell walls of cereal grains. Plant cell walls determine the quality of most plant-based products used in modern human societies, yet the regulatory mechanisms responsible for their modulation are not well understood. Key distinguishing features of the Project will be the international, integrative, and multidisciplinary approach towards addressing this major challenge in plant biology and the potential of the fundamental scientific discoveries to benefit end-users in the food, feed and beverage industries.Read moreRead less
Isolation and functional characterisation of a pathogen meta effector able to inhibit detection of multiple disease effectors by resistant plants. The rust fungi are a major economic threat to crop production in Australia. This project will investigate the molecular mechanism used by a rust fungus to prevent detection of multiple disease-inducing proteins by resistant plants and generate knowledge that will lead to the development of new and more effective disease control strategies.
Characterisation of PQ loop proteins in plants: are they voltage insensitive nonselective cation channels? Millions of hectares of Australian agricultural land are affected by salinity. This results in the loss of hundreds of millions of dollars in revenue each year. The identification of the pathway for the initial influx of Na+ into plants from the soil will be important in helping to develop crop plants that are salt tolerant. This will increase our understanding of the mechanisms of salinity ....Characterisation of PQ loop proteins in plants: are they voltage insensitive nonselective cation channels? Millions of hectares of Australian agricultural land are affected by salinity. This results in the loss of hundreds of millions of dollars in revenue each year. The identification of the pathway for the initial influx of Na+ into plants from the soil will be important in helping to develop crop plants that are salt tolerant. This will increase our understanding of the mechanisms of salinity tolerance, an area of great importance to Australian agriculture and environmental sustainability. The future applications of this work will increase agricultural productivity and enhance the quality of life for both Australians and the international community.Read moreRead less
Diversity in large crop genomes via enhanced recombination. The project aims to understand genetic and environmental factors that limit how fast genomic combinations can be generated by modifying the recombination rates between chromosomes. Plant breeding is based around genetic diversity, but modern breeding programs have captured only a small proportion of the variation available in wild relatives and land races. Knowledge of diversity in this wild germplasm pool is increasing and the challeng ....Diversity in large crop genomes via enhanced recombination. The project aims to understand genetic and environmental factors that limit how fast genomic combinations can be generated by modifying the recombination rates between chromosomes. Plant breeding is based around genetic diversity, but modern breeding programs have captured only a small proportion of the variation available in wild relatives and land races. Knowledge of diversity in this wild germplasm pool is increasing and the challenge is to quickly and efficiently introduce this variation into elite lines. This project’s findings are expected to transform wheat and barley breeding methods by unlocking the genetic diversity to produce new varieties. This will enhance and protect a critical and valuable rural industry.Read moreRead less
Finding the missing links in salt and water transport in plants. Grain crops and horticultural plants use proteins called aquaporins to move water across cell membranes, but a group of these proteins can also transport some important nutrient ions as well as toxic sodium ions. This project aims to reveal the molecular pathways that regulate water and ion transport via aquaporins using advanced techniques in biophysics and molecular biology. These results will provide novel insights into how plan ....Finding the missing links in salt and water transport in plants. Grain crops and horticultural plants use proteins called aquaporins to move water across cell membranes, but a group of these proteins can also transport some important nutrient ions as well as toxic sodium ions. This project aims to reveal the molecular pathways that regulate water and ion transport via aquaporins using advanced techniques in biophysics and molecular biology. These results will provide novel insights into how plants coordinate and adapt to changing water and salt conditions, addressing a missing link in how ions and water move in and out of plant vacuoles. Benefits include an expanded, innovative range of targets for plant breeding programs to improve plant productivity in our changing climate.Read moreRead less
How SEP-like genes determine cereal inflorescence architecture. This project aims to understand the morphological diversity of inflorescence architecture between cereal crop species. To do so, this project will identify functions and analyse the regulatory networks of conserved SEPALLATA genes (SEPs). This will enable them to determine cereal inflorescence morphogenesis of rice (branching) and barley (non-branching), representing the most important cereals. Identifying and understanding rice and ....How SEP-like genes determine cereal inflorescence architecture. This project aims to understand the morphological diversity of inflorescence architecture between cereal crop species. To do so, this project will identify functions and analyse the regulatory networks of conserved SEPALLATA genes (SEPs). This will enable them to determine cereal inflorescence morphogenesis of rice (branching) and barley (non-branching), representing the most important cereals. Identifying and understanding rice and barley SEPs, their direct targets and interactors, and how they regulate inflorescence branches and spikelets in both species is expected to provide evolutionary and developmental insights and targets to improve for crop yield. A molecular understanding of the regulatory network that underpins inflorescence shape and grain number will advance fundamental biology, and could form the basis for significant yield improvements by manipulating key points in the developmental pathway.Read moreRead less