Meiotic recombination in Neurospora crassa: a model for the process in humans and other multicellular eukaryotes. Genes are shuffled by recombination during meiosis in the sexual cycle of higher organisms. This is best understood in yeast. Our findings show Neurospora recombination differs from yeast recombination. It is more tolerant of sequence mismatch, differs in the relative frequencies of gene conversion and crossing over, has frequently interrupted conversion tracts and has transacting ge ....Meiotic recombination in Neurospora crassa: a model for the process in humans and other multicellular eukaryotes. Genes are shuffled by recombination during meiosis in the sexual cycle of higher organisms. This is best understood in yeast. Our findings show Neurospora recombination differs from yeast recombination. It is more tolerant of sequence mismatch, differs in the relative frequencies of gene conversion and crossing over, has frequently interrupted conversion tracts and has transacting genes controlling recombination hotspot activity. We propose to genetically dissect Neurospora recombination which appears to be a closer model for recombination in humans and other higher eukaryotes, where understanding recombination can assist control of genetic disease, efficient breeding in agriculture and our understanding of evolution.Read moreRead less
A genomic approach to the mechanism of meiotic recombination in Neurospora. Recombination shuffles DNA sequences between homologous chromosomes during the reduction division in the life cycle of higher organisms. Along with mutation, it is a key process in evolution. Understanding of the molecular processes involved in recombination is largely based on yeast, which is intolerant of significant levels of sequence mismatch, limiting the resolution of analyses of normal recombination events. We hav ....A genomic approach to the mechanism of meiotic recombination in Neurospora. Recombination shuffles DNA sequences between homologous chromosomes during the reduction division in the life cycle of higher organisms. Along with mutation, it is a key process in evolution. Understanding of the molecular processes involved in recombination is largely based on yeast, which is intolerant of significant levels of sequence mismatch, limiting the resolution of analyses of normal recombination events. We have shown that Neurospora, like other less tractable multicellular eukaryotes, is tolerant of sequence mismatch, allowing high resolution analysis of individual recombination events. This project will build on fundamental advances we have already made in understanding how recombination occurs.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