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
Cross sections for electron scattering from molecules and radicals of technological and environmental relevance. We will use two state of the art crossed beam spectrometers to measure absolute differential and integral cross sections for low energy electron scattering from molecules and their molecular fragments (radicals). The species to be considered are those of significant industrial (e.g. C2F4, C4F8 and CF2) and environmental (e.g. CO2 and H2O) interest, with the cross sections we will mea ....Cross sections for electron scattering from molecules and radicals of technological and environmental relevance. We will use two state of the art crossed beam spectrometers to measure absolute differential and integral cross sections for low energy electron scattering from molecules and their molecular fragments (radicals). The species to be considered are those of significant industrial (e.g. C2F4, C4F8 and CF2) and environmental (e.g. CO2 and H2O) interest, with the cross sections we will measure being crucial to our modelling both the processes involved in plasma enhanced chemical vapour desposition of semiconductor devices and the spectral emission characteristics of planetary atmospheres. The modelling will be conducted self-consistently with our enhanced statistical equilibrium simulation code, which is unique to Australia.Read moreRead less
Solving the Mysteries of Monotreme Chromosomes. The peculiar chromosomes of Australia's platypus and echidna have been debated for more than 30 years. Classical cytology cannot resolve the puzzling sex chromosome system, or to sort out the bizarre translocation chain (unique in vertebrates) and deduce how it segregates to make viable zyotes. I will microdissect individual chromosomes, and use DNA ?paints? from them (and gene probes isolated by them) to detect homologies between unpaired chromoso ....Solving the Mysteries of Monotreme Chromosomes. The peculiar chromosomes of Australia's platypus and echidna have been debated for more than 30 years. Classical cytology cannot resolve the puzzling sex chromosome system, or to sort out the bizarre translocation chain (unique in vertebrates) and deduce how it segregates to make viable zyotes. I will microdissect individual chromosomes, and use DNA ?paints? from them (and gene probes isolated by them) to detect homologies between unpaired chromosomes at mitosis, meiosis and in sperm. I will use immunohistochemistry to clarify chromosome pairing and recombination at meiosis. This will answer some important general questions about chromosome behaviour and sex chromosome evolution.
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Inter- and Intra-molecular interactions probed by electron momentum spectroscopy. High-resolution electron momentum spectroscopy (EMS) will be used to study bonding (intra-molecular interactions) in complex oriented organic species. This will allow us, in conjunction with density functional theory calculations, to evaluate the basis sets and exchange-correlation (XC) functionals employed in those calculations, thereby potentially enabling quantum chemists to build more physically accurate XC-fu ....Inter- and Intra-molecular interactions probed by electron momentum spectroscopy. High-resolution electron momentum spectroscopy (EMS) will be used to study bonding (intra-molecular interactions) in complex oriented organic species. This will allow us, in conjunction with density functional theory calculations, to evaluate the basis sets and exchange-correlation (XC) functionals employed in those calculations, thereby potentially enabling quantum chemists to build more physically accurate XC-functionals and basis sets. As chemistry largely occurs in solution, the future will increasingly focus on solvated species. Consequently, we are also initiating an EMS study of the electronic wavefunctions of solvated species with our recently developed "clusters" EMS spectrometer. This will provide the first data on the electronic wavefunctions involved in inter-molecular interactions.Read moreRead less
The nature, extent and effect of infant removal by child protection. This project aims to provide new knowledge about the nature, extent and effect of removals of babies from their parents in Australia. Removal is the highest level of intervention by the child protection system, and one which some mothers experienced on multiple occasions. Little is known, however, about its incidence and effects, nor whether there are over-represented groups (e.g. Aboriginal mothers and babies) who would respon ....The nature, extent and effect of infant removal by child protection. This project aims to provide new knowledge about the nature, extent and effect of removals of babies from their parents in Australia. Removal is the highest level of intervention by the child protection system, and one which some mothers experienced on multiple occasions. Little is known, however, about its incidence and effects, nor whether there are over-represented groups (e.g. Aboriginal mothers and babies) who would respond to targeted interventions. This project aims to identify appropriate early intervention and prevention strategies, preventing the need for babies to spend their whole childhood in care at great financial and societal cost.Read moreRead less