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.
Read moreRead less
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
Choosing when to be sexual: clonal and sexual reproduction in a population of honey bees. Sex is costly. There is the cost of finding a mate and the genome of offspring must be shared with the mating partner. Despite these costs, sex is common in animals, so the benefits of sex must be substantial. Benefits may include the prevention of inbreeding and generating variable offspring. Exploring the trade off between sex and cloning requires a model system where individuals can choose to reproduce ....Choosing when to be sexual: clonal and sexual reproduction in a population of honey bees. Sex is costly. There is the cost of finding a mate and the genome of offspring must be shared with the mating partner. Despite these costs, sex is common in animals, so the benefits of sex must be substantial. Benefits may include the prevention of inbreeding and generating variable offspring. Exploring the trade off between sex and cloning requires a model system where individuals can choose to reproduce sexually or asexually. This project will explore a population of honey bees where a genetic mutation allows queens to clone themselves or reproduce sexually. We will reveal the unusual genetic mechanisms behind this ability and show how they are used by queens and workers to increase their reproductive success.Read moreRead less
Isolation and characterization of genes regulating female reproductive organ development in plants. Genes that regulate female reproductive organ development are of immense value for Australia as tools for seed improvement. Those from our preliminary screen have convinced our industry partners that they can be agents for engineering of apomixis or creation of fertile seed without fertilisation. This will allow the capture of hybrid vigour in wheat and rice, for which commercial hybrid seed prod ....Isolation and characterization of genes regulating female reproductive organ development in plants. Genes that regulate female reproductive organ development are of immense value for Australia as tools for seed improvement. Those from our preliminary screen have convinced our industry partners that they can be agents for engineering of apomixis or creation of fertile seed without fertilisation. This will allow the capture of hybrid vigour in wheat and rice, for which commercial hybrid seed production is not currently available. In wheat alone, apomixis presents for Australia an economic value of more than Aus$ ½ billion per annum. Furthermore, controlled apomixis will accelerate breeding programs that will bring drought resistance and minimal fertiliser requiring varieties to the farmer.Read moreRead less