Organization, function and evolution of marsupial Y chromosomes. The Y chromosome of humans and other mammals contains only a few genes, most specialized for male sex and reproduction. How the Y chromosome evolved to be so peculiar has been debated for 90 years. It began as an ordinary chromosome, but has degraded until there is almost nothing left, and it is likely to disappear in about 13 million years. Molecular characterization of the Y chromosomes of distantly related mammals could serve to ....Organization, function and evolution of marsupial Y chromosomes. The Y chromosome of humans and other mammals contains only a few genes, most specialized for male sex and reproduction. How the Y chromosome evolved to be so peculiar has been debated for 90 years. It began as an ordinary chromosome, but has degraded until there is almost nothing left, and it is likely to disappear in about 13 million years. Molecular characterization of the Y chromosomes of distantly related mammals could serve to 're-run the evolutionary tape', but the Y chromosome has been left out of whole genome sequencing because it is hard to do efficiently. We developed a novel technique to isolate DNA sequences and genes on the Y chromosome in three species of marsupials, which are especially valuable because they are so different from human and mouse.Read moreRead less
Sex in Dragons: Probing the genotype-phenotype interaction in sex determination. Reptiles have two modes of sex determination: genetic (GSD) and temperature dependent (TSD). We will determine if there is an underlying mechanism of sex determination common to TSD and GSD reptiles by comparing the genomes of two sister species of dragon lizard that differ in their mode of sex determination. This study will provide new insights to the mechanism of sex determination in vertebrates and will test the ....Sex in Dragons: Probing the genotype-phenotype interaction in sex determination. Reptiles have two modes of sex determination: genetic (GSD) and temperature dependent (TSD). We will determine if there is an underlying mechanism of sex determination common to TSD and GSD reptiles by comparing the genomes of two sister species of dragon lizard that differ in their mode of sex determination. This study will provide new insights to the mechanism of sex determination in vertebrates and will test the proposition that sex determination results from the interaction between environmental influences and an underlying genetic component.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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Many Ys in monotremes: multiple sex chromosomes and sex determination in platypus and echidna. Platypus and Echidna are Australian icons, even featuring on our coins. Their unusual biology and ancient relationship to humans make them unique for understanding the mammalian genome, as demonstrated by our recent discovery of ten sex chromosomes in platypus that link mammal and bird sex. Still little is known about their genome, embryo development and how sex is determined. We will identify new gene ....Many Ys in monotremes: multiple sex chromosomes and sex determination in platypus and echidna. Platypus and Echidna are Australian icons, even featuring on our coins. Their unusual biology and ancient relationship to humans make them unique for understanding the mammalian genome, as demonstrated by our recent discovery of ten sex chromosomes in platypus that link mammal and bird sex. Still little is known about their genome, embryo development and how sex is determined. We will identify new genes on all ten sex chromosomes and investigate how they determine sex. The set up of an Australian Monotreme Resource Centre will be crucial for this research and attract worldwide high profile collaborations. We will answer important general questions in monotreme biology and contribute to our understanding of sexual abnormalities in humans.Read moreRead less
Differential expression and functional analysis of genes controlling metamorphosis and early neurogenesis of a model lower animal, the coral Acropora. This study will analyse, at a molecular level, the response of coral larvae to stimuli inducing settlement from the plankton and the process of establishment of a sessile, calcified colony. The knowledge gained will facilitate induction of settlement on demand in the most effective way. We will characterise known candidate genes which may be invo ....Differential expression and functional analysis of genes controlling metamorphosis and early neurogenesis of a model lower animal, the coral Acropora. This study will analyse, at a molecular level, the response of coral larvae to stimuli inducing settlement from the plankton and the process of establishment of a sessile, calcified colony. The knowledge gained will facilitate induction of settlement on demand in the most effective way. We will characterise known candidate genes which may be involved in settlement, and reveal a more complete picture using subtractive hybridisation. Studies of the nervous system and the changes that it undergoes at metamorphosis will promote understanding of the control of metamorphosis, and insights into how more complex nervous systems may have evolved.Read moreRead less
ARC Centre for Kangaroo Genome. In this Australian-led Kangaroo Genome Project, we will map and characterize the tammar wallaby genome at the molecular level. Marsupial genomes are uniquely valuable because they provide comparisons that reveal new human genes, regulatory sequences and marsupial-specific genes. These will deliver new products and information useful for medicine, industry, agriculture and conservation. We will construct integrated genetic and physical maps of the genome, clone the ....ARC Centre for Kangaroo Genome. In this Australian-led Kangaroo Genome Project, we will map and characterize the tammar wallaby genome at the molecular level. Marsupial genomes are uniquely valuable because they provide comparisons that reveal new human genes, regulatory sequences and marsupial-specific genes. These will deliver new products and information useful for medicine, industry, agriculture and conservation. We will construct integrated genetic and physical maps of the genome, clone the whole genome as large inserts in BAC vectors, and build a "golden path" with minimal overlap. We will construct libraries of expressed genes from tammar tissues and array them for use in analysing gene expression.Read moreRead less
New models for the role of chromatin in controlling inducible gene expression. This proposal aims to test novel models of how packaging of DNA in the nucleus plays a fundamental role in gene expression. Understanding these concepts is important in the context of successful gene therapy where major hurdles need to be overcome. This work also has implications for somatic cell therapy since it is important to understand how genes are expressed in order to successfully reprogram cells. Both of these ....New models for the role of chromatin in controlling inducible gene expression. This proposal aims to test novel models of how packaging of DNA in the nucleus plays a fundamental role in gene expression. Understanding these concepts is important in the context of successful gene therapy where major hurdles need to be overcome. This work also has implications for somatic cell therapy since it is important to understand how genes are expressed in order to successfully reprogram cells. Both of these areas are important to the Biotechnology industry. Answering questions about higher order chromatin structure in gene transcription will provide cutting edge, innovative knowledge that will have international significance. Read moreRead less
Epigenetic silencing in vertebrates: evolution and function from the bottom-up. The primary benefits are contribution to Australia's knowledge base and raising the profile of functional genomics in Australia, with the research priority of Frontier Technologies for Building and Transforming Australian Industries and priority goals in Breakthrough Science and Frontier Technologies. This project focuses on important biological questions surrounding gene regulation and sex chromosome evolution. Inte ....Epigenetic silencing in vertebrates: evolution and function from the bottom-up. The primary benefits are contribution to Australia's knowledge base and raising the profile of functional genomics in Australia, with the research priority of Frontier Technologies for Building and Transforming Australian Industries and priority goals in Breakthrough Science and Frontier Technologies. This project focuses on important biological questions surrounding gene regulation and sex chromosome evolution. International attention has already resulted in genome characterization of Australian icons (wallaby, Tasmanian devil and platypus), more research on these, and other Australian animals, will further highlight the importance of Australian fauna and impact positively on our scientific profile.Read moreRead less
Origin and evolution of genes on the human X chromosome. Two groups of functionally related genes are found on the human X chromosome in disproportionately high numbers. I will test whether an uneven distribution of genes is common in mammalian genomes, or whether the human X is special. I will test hypotheses of how the gene groups arose on the human X by comparing their location and expression patterns in other mammals, and other vertebrates. It will then be clear whether the ancestral autosom ....Origin and evolution of genes on the human X chromosome. Two groups of functionally related genes are found on the human X chromosome in disproportionately high numbers. I will test whether an uneven distribution of genes is common in mammalian genomes, or whether the human X is special. I will test hypotheses of how the gene groups arose on the human X by comparing their location and expression patterns in other mammals, and other vertebrates. It will then be clear whether the ancestral autosome was ?chosen?, whether it ?selfishly? accumulated these genes, or whether the function of genes changed in response to selective pressures.Read moreRead less
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