Small is beautiful: Did gene-rich regions of mammal chromosomes evolve from microchromosomes? Most birds and reptile genomes feature many tiny microchromosomes. These are not junk, as previously thought, but contain most of the genes. Mammals lack microchromosomes, but contain gene-rich regions with similar attributes. We suggest that microchromosomes originated by genome duplication, and evolved into the gene-rich regions of mammalian chromosomes. We will test this hypothesis by comparing seque ....Small is beautiful: Did gene-rich regions of mammal chromosomes evolve from microchromosomes? Most birds and reptile genomes feature many tiny microchromosomes. These are not junk, as previously thought, but contain most of the genes. Mammals lack microchromosomes, but contain gene-rich regions with similar attributes. We suggest that microchromosomes originated by genome duplication, and evolved into the gene-rich regions of mammalian chromosomes. We will test this hypothesis by comparing sequences and genes in microchromosomes of birds, reptiles and monotremes. This will clarify the origin and evolution of the ?microgenome?, establish its suitability as a model for vertebrate genome organisation, and demonstrate whether microchromosomes are the ancestors of the gene-rich regions of mammalian chromosomes.Read moreRead less
Endosymbiotic DNA transfer. Interorganellar DNA movement is a major force in evolution. In higher organisms, the prokaryotic ancestors of mitochondria and chloroplasts donated many genes to the nucleus. Plants have unique potential in studies of the mechanisms that have driven genome evolution. We established experimentally that DNA moves from the chloroplast to the nucleus at high frequency and this provided us with a world lead in this scientifically new area. The relocated genes contribute to ....Endosymbiotic DNA transfer. Interorganellar DNA movement is a major force in evolution. In higher organisms, the prokaryotic ancestors of mitochondria and chloroplasts donated many genes to the nucleus. Plants have unique potential in studies of the mechanisms that have driven genome evolution. We established experimentally that DNA moves from the chloroplast to the nucleus at high frequency and this provided us with a world lead in this scientifically new area. The relocated genes contribute to the number and diversity of genes and gene function. Genetically manipulated (GM) crops use the chloroplast compartment to make high levels of protein, necessitating a full understanding of how transgenes behave within the cellular and the external environment.Read moreRead less
Trafficking of DNA between chloroplast and nucleus in higher plants. Reliably high levels of diverse proteins can be produced in plant chloroplasts. Environmental risks are considered low for chloroplast genes because they are not transmitted by pollen. However, we recently discovered that DNA escapes from the tobacco chloroplast to the nucleus with unexpectedly high frequency. The associated environmental risks require immediate investigation. This project will determine the fate of chloroplast ....Trafficking of DNA between chloroplast and nucleus in higher plants. Reliably high levels of diverse proteins can be produced in plant chloroplasts. Environmental risks are considered low for chloroplast genes because they are not transmitted by pollen. However, we recently discovered that DNA escapes from the tobacco chloroplast to the nucleus with unexpectedly high frequency. The associated environmental risks require immediate investigation. This project will determine the fate of chloroplast DNA that has moved to the nuclear genome and gain insight into the evolutionary and environmental consequences of chloroplast DNA escape. The ubiquity of DNA escape also will be studied in an edible crop with a small genome, tomato.Read moreRead less
Analysis of interorganellar transposition of DNA. The movement of DNA between organelles is a major driving force in the eukaryotic evolution. In yeast about 75% of all nuclear genes may derive from protomitochondria. Though DNA transfer per se continues in all higher cells, including mammals, in most species the functional transfer of genes has stopped. It continues at a high rate in plants, giving them unique potential in evolutionary studies of the genome. We established experimentally that D ....Analysis of interorganellar transposition of DNA. The movement of DNA between organelles is a major driving force in the eukaryotic evolution. In yeast about 75% of all nuclear genes may derive from protomitochondria. Though DNA transfer per se continues in all higher cells, including mammals, in most species the functional transfer of genes has stopped. It continues at a high rate in plants, giving them unique potential in evolutionary studies of the genome. We established experimentally that DNA moves frequently from the plastid (chloroplast) to the nucleus. We now aim to measure the frequency of DNA transposition from the plastid to the mitochondrion. If transposition is sufficiently frequent, the approach can be used to transformation the mitochondrial genome.Read moreRead less
The molecular basis of endosymbiotic evolution. First: Timmis has a 20 year, pioneering reputation in this research area which has recently emerged as a major focus in evolutionary genetics, genomics and GM crop technology. Four years of recent ARC funding has enabled us to remain internationally competitive and significant papers and collaborative reviews in high-impact journals have resulted, to the benefit of Australia's reputation in biolological science. Second: our recent results have caus ....The molecular basis of endosymbiotic evolution. First: Timmis has a 20 year, pioneering reputation in this research area which has recently emerged as a major focus in evolutionary genetics, genomics and GM crop technology. Four years of recent ARC funding has enabled us to remain internationally competitive and significant papers and collaborative reviews in high-impact journals have resulted, to the benefit of Australia's reputation in biolological science. Second: our recent results have caused major debate about containment of GM crops. The knowledge gained from this research will provide essential information to ensure against environmental and human problems associated with transgene escape from GM crops into wild species.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
Structural reorganization of the hymenopteran mitochondrial genome. This study will be the first detailed investigation of the evolution of mt genome reorganization, and as such it will identify the processes that shape the evolution of a molecule widely used to interpret phylogeny. A description of the processes that lead to mt genome reorganization will have a substantial impact on our understanding in two areas of mt biology; (1) the discovery of new molecular phenomena that impact on the or ....Structural reorganization of the hymenopteran mitochondrial genome. This study will be the first detailed investigation of the evolution of mt genome reorganization, and as such it will identify the processes that shape the evolution of a molecule widely used to interpret phylogeny. A description of the processes that lead to mt genome reorganization will have a substantial impact on our understanding in two areas of mt biology; (1) the discovery of new molecular phenomena that impact on the organization and evolution of this genome, and (2) the interpretation of its phylogenetic content. It will establish our research group as a leader in the field of evolutionary genetics. Training of high quality students, with exposure to international researchers, will be a significant component of this program.Read moreRead less
Road rules for traffic on DNA - gene regulation by encounters between transcribing RNA polymerases and DNA-bound proteins. This project addresses a widespread but poorly understood phenomenon in gene regulation. The work will support Australian industries by supplying new tools for manipulation of gene expression for industrial and medical applications and will provide unique opportunities for Australian students in this emerging field.
Developing biogeographic know-how: Improving species divergence and dispersal estimations to examine geological and climatic evolutionary drivers. Anthropogenic activity over the last 150 years is now dramatically changing our global climate and ecosystems. The impact on biodiversity is already evident, and large-scale floral and faunal extinctions are predicted. This study unites a cohort of international experts in an interdisciplinary team to develop new molecular and mathematical methods to ....Developing biogeographic know-how: Improving species divergence and dispersal estimations to examine geological and climatic evolutionary drivers. Anthropogenic activity over the last 150 years is now dramatically changing our global climate and ecosystems. The impact on biodiversity is already evident, and large-scale floral and faunal extinctions are predicted. This study unites a cohort of international experts in an interdisciplinary team to develop new molecular and mathematical methods to expand our fundamental knowledge on how geological and global climate change have affected our world's species components and ecosystems in the past. This research is of environmental significance and global importance as it will improve our ability to predict how species behave under future predicted climate scenarios.Read moreRead less
Non-coding RNAs in mammalian reproduction. This project aims to investigate the role of non-coding RNAs in mammalian sex chromosome biology and reproduction. Non-protein coding RNAs are a major regulatory mechanism in eukaryotic genomes; they can bind other RNAs or chromatin modifying complexes. However, the evolutionary trajectory and function of non-coding RNAs in sex chromosome biology and sexual development is largely unknown. This project will study non-coding RNAs in Australian mammals to ....Non-coding RNAs in mammalian reproduction. This project aims to investigate the role of non-coding RNAs in mammalian sex chromosome biology and reproduction. Non-protein coding RNAs are a major regulatory mechanism in eukaryotic genomes; they can bind other RNAs or chromatin modifying complexes. However, the evolutionary trajectory and function of non-coding RNAs in sex chromosome biology and sexual development is largely unknown. This project will study non-coding RNAs in Australian mammals to try to answer fundamental questions about how non-coding RNAs function in mammalian sexual development.Read moreRead less