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
Discovery Early Career Researcher Award - Grant ID: DE190101069
Funder
Australian Research Council
Funding Amount
$390,000.00
Summary
Adaptation and diversification of the first peoples of Sahul. This project aims to further advance work on the genetic history of Indigenous Australians and Papuans that has revealed that Aboriginal Australians have inhabited a variety of diverse and challenging environments for approximately 50,000 years. Using novel techniques for extraction of human DNA from soil and the use of cutting-edge graph-based methods, hundreds of Indigenous Australian and Papuan genomes will be analysed. This projec ....Adaptation and diversification of the first peoples of Sahul. This project aims to further advance work on the genetic history of Indigenous Australians and Papuans that has revealed that Aboriginal Australians have inhabited a variety of diverse and challenging environments for approximately 50,000 years. Using novel techniques for extraction of human DNA from soil and the use of cutting-edge graph-based methods, hundreds of Indigenous Australian and Papuan genomes will be analysed. This project expects to generate new knowledge by filling in the gaps in the Australian genetic record via ancient human DNA from sediments. Expected outcomes from this project are producing a detailed picture of genomic adaptation in Indigenous Australians and Papuans and creating a comprehensive genetic history of the First Peoples of Sahul.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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Genetic control of floral architecture. Different flowers have different designs, and so the design must ultimately be controlled by genes. We have identified a gene that keeps sepals separate, and promotes the initiation of petals. We think it does this by a novel growth suppression mechanism, and will now deduce its molecular and cellular basis. This will help maintain Australia's strength in fundamental plant biology. Also, by understanding how sepals and petals arise in a model laboratory sp ....Genetic control of floral architecture. Different flowers have different designs, and so the design must ultimately be controlled by genes. We have identified a gene that keeps sepals separate, and promotes the initiation of petals. We think it does this by a novel growth suppression mechanism, and will now deduce its molecular and cellular basis. This will help maintain Australia's strength in fundamental plant biology. Also, by understanding how sepals and petals arise in a model laboratory species, we can generalise for many species, including economic plants. Thus it may be possible to make designer crops through targeted genetic changes to their floral structure.Read moreRead less
Control of plant organ development by the PETAL LOSS gene of Arabidopsis. We have discovered a new gene in the model laboratory plant Arabidopsis thaliana that is involved in sepal and petal development. It encodes a transcription factor that apparently acts by repressing growth in the inter-sepal zone of flowers where petals arise. We now aim to determine how this growth suppression occurs, and whether it extends to leaves where the gene is also expressed. Control of the initiation and sculptur ....Control of plant organ development by the PETAL LOSS gene of Arabidopsis. We have discovered a new gene in the model laboratory plant Arabidopsis thaliana that is involved in sepal and petal development. It encodes a transcription factor that apparently acts by repressing growth in the inter-sepal zone of flowers where petals arise. We now aim to determine how this growth suppression occurs, and whether it extends to leaves where the gene is also expressed. Control of the initiation and sculpturing of plant organs by site-specific inhibition of growth is a newly discovered mechanism that may be useful in manipulating plant architecture.Read moreRead less
Understanding how auxin and dorsoventral patterning are coordinated in plants. This study will help reveal for the first time how the outgrowth of leaves, flowers and floral organs is coordinated by tissue patterning genes and the plant growth hormone auxin. All plants grow in this way, and our findings, made using a model laboratory plant, will be applicable to crop species as well. Thus we will both expand our core knowledge of how multicellular organisms are constructed, and also generate pos ....Understanding how auxin and dorsoventral patterning are coordinated in plants. This study will help reveal for the first time how the outgrowth of leaves, flowers and floral organs is coordinated by tissue patterning genes and the plant growth hormone auxin. All plants grow in this way, and our findings, made using a model laboratory plant, will be applicable to crop species as well. Thus we will both expand our core knowledge of how multicellular organisms are constructed, and also generate possibilities for modifying the patterns of leaf and flower development in agricultural and horticultural species. Crops with larger leaves, or flowers of different structure, may result.Read moreRead less
Understanding the evolution of the alternation of generations in the land plant life cycle. This project will investigate the genetic basis and evolution of the land plant life cycle, in which both haploid and diploid phases consist of complex multicellular bodies. The project's findings, which will be made using two model laboratory plants, will be applicable to all plants and will help understand important processes such as pollen and seed production.
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