The Role Of Heterochromatin In Regulating Cellular Proliferation And Development
Funder
National Health and Medical Research Council
Funding Amount
$504,000.00
Summary
Fundamental to the development of a multicellular organism is that for each cell type performing a specialised function, a different set of genes are turned on with the remainder being shut off. One of the most significant unanswered questions in biology is how a cell-type specific gene expression profile is established during early development. The answer to this question has important implications in understanding normal and abnormal cellular processes. Gene expression in a cell occurs in the ....Fundamental to the development of a multicellular organism is that for each cell type performing a specialised function, a different set of genes are turned on with the remainder being shut off. One of the most significant unanswered questions in biology is how a cell-type specific gene expression profile is established during early development. The answer to this question has important implications in understanding normal and abnormal cellular processes. Gene expression in a cell occurs in the nucleus where genes are stored. In the nucleus, DNA is not in a free form but is covered with an equivalent weight of protein (histones) to form a structure known as chromatin. It has become clear that the chromatin structure encompassing a gene is the critical factor that determines whether a gene is expressed or silenced. We propose that developmental and cell-type specific mechanisms operate in a cell to assemble genes into highly specialised chromatin structures that permit (euchromatin) or restrict (heterochromatin) gene expression. In other words, the genome of each different cell type is organised into a unique and dynamic chromatin pattern and this pattern determines the gene expression profile. This investigation will show that the critical cellular mechanism that determines the chromatin pattern for a particular cell type is the regulation of the quantity and quality of heterochromatin. Specifically, we will demonstrate that this is achieved, in a developmental and tissue specific manner, by changing the make-up of chromosomal domains through the replacement of histone proteins with specialised forms of histones called variants . In addition, we will expose a new mechanism of how heterochromatin formation controls the rate of cellular proliferation. This information will provide new insights into how gene expression profiles are established at precise times in early development, and offer a new strategy to inhibit the proliferation of cancer cells.Read moreRead less
Constructing an embryo. This project investigates the cellular and molecular mechanisms underlying temporal and spatial organisation in the eutherian preimplantation embryo. It will examine: the relative roles of cell cycle and circadian clocks in developmental timing; the molecular mechanism by which intercellular adhesion patterns influence spatial organisation; the extent to which marsupials use similar timing and spatial localisation mechanisms to eutherians; the impact of in-vitro manipulat ....Constructing an embryo. This project investigates the cellular and molecular mechanisms underlying temporal and spatial organisation in the eutherian preimplantation embryo. It will examine: the relative roles of cell cycle and circadian clocks in developmental timing; the molecular mechanism by which intercellular adhesion patterns influence spatial organisation; the extent to which marsupials use similar timing and spatial localisation mechanisms to eutherians; the impact of in-vitro manipulations over the first 5 days of mouse pregnancy on embryonic temporal and spatial organisation.Read moreRead less
Rapid functional analysis of genes involved in skeletal development. Abnormalities of the skeleton are of enormous clinical significance in terms of both number of individuals affected and the cost of treatment. Data derived from this project will underpin targeted research on the mechanisms of inherited and common diseases of cartilage and bone, yielding novel diagnostic and therapeutic targets. In addition, the improved knowledge of cartilage and bone cell development will inform new approache ....Rapid functional analysis of genes involved in skeletal development. Abnormalities of the skeleton are of enormous clinical significance in terms of both number of individuals affected and the cost of treatment. Data derived from this project will underpin targeted research on the mechanisms of inherited and common diseases of cartilage and bone, yielding novel diagnostic and therapeutic targets. In addition, the improved knowledge of cartilage and bone cell development will inform new approaches for developing stem cell therapies and the production of novel biomaterials for the repair of bones and joints. The outcomes of this study will therefore benefit the full spectrum of society from infants to the aged.Read moreRead less
Genetic analysis of cohesin function and regulation in Drosophila. In yeast, a multiprotein complex, called cohesin, holds newly replicated chromatids together until the cell is ready to partition each chromatid into its daughter cells. We and others have shown that cohesins are regulated differently in animal cells. We propose to combine classical genetic analyses with two new and innovative techniques, time-lapse confocal microscopy of fluorescent proteins in living cells and gene-specific kno ....Genetic analysis of cohesin function and regulation in Drosophila. In yeast, a multiprotein complex, called cohesin, holds newly replicated chromatids together until the cell is ready to partition each chromatid into its daughter cells. We and others have shown that cohesins are regulated differently in animal cells. We propose to combine classical genetic analyses with two new and innovative techniques, time-lapse confocal microscopy of fluorescent proteins in living cells and gene-specific knockout techniques to study key cohesin regulators in Drosophila. These studies will provide us with novel insights into how multicellular organisms regulate the structure and stability of their chromosomes.Read moreRead less
Molecular mechanisms of stem cell self-renewal. Muscle growth and regeneration is critically dependent on its stem cell compartment. We have discovered that the p38 MAPK pathway is essential for stem cell self-renewal in the C2C12 myogenic cell line. This proposal seeks to understand the molecular basis of stem cell self-renewal in skeletal muscles, data that may be applicable to many stem cell systems, and to the enormous promise of stem cell therapies for injury and diseases of the aged. We wi ....Molecular mechanisms of stem cell self-renewal. Muscle growth and regeneration is critically dependent on its stem cell compartment. We have discovered that the p38 MAPK pathway is essential for stem cell self-renewal in the C2C12 myogenic cell line. This proposal seeks to understand the molecular basis of stem cell self-renewal in skeletal muscles, data that may be applicable to many stem cell systems, and to the enormous promise of stem cell therapies for injury and diseases of the aged. We will attempt to alter the balance of stem cell production by enforced p38 expression, and take microarray and proteomics approaches to define stem cell pathways.Read moreRead less
Preventing genetic damage with BIX - a novel player in the DNA damage response pathway. Defects in the DNA damage-response pathway underpin many human genetic disorders and diseases, including cancer. A detailed understanding of this process has enormous implications for future medicine. Our characterization of a novel protein involved in DNA damage signalling will help in screening inhibitors of this pathway that could be applied in chemo-and/or radiotherapy. This proposal will place Australia ....Preventing genetic damage with BIX - a novel player in the DNA damage response pathway. Defects in the DNA damage-response pathway underpin many human genetic disorders and diseases, including cancer. A detailed understanding of this process has enormous implications for future medicine. Our characterization of a novel protein involved in DNA damage signalling will help in screening inhibitors of this pathway that could be applied in chemo-and/or radiotherapy. This proposal will place Australia among the leaders in this internationally significant and highly competitive area of research leading to the creation of new compounds. Capture of this technology will create the opportunity for IP income, novel exports and new enterprises for Australia.Read moreRead less
Oxidative Damage and Cell Ageing. This research will benefit Australia by providing a fundamental understanding of how cells age. This will have immediate international impact at the scientific level and will inform strategies to reduce the rate of ageing and alleviation of age-related disorders. In the longer term the research may provide commercial and social outcomes by identifying antioxidant systems that will provide a genuine benefit in reducing ageing.
Cellular Responses to Oxidative Damage: Cell Aging. The aim of this project is to identify the mechanisms by which oxidative stress and free radical damage cause cell aging. This work will make a significant contribution to our understanding of the aging process in cells by identifying the major reactive oxygen species that contribute to cell aging, which defence systems and antioxidants provide the greatest degree of protection, what damage accumulates as cells age and which genetic systems ar ....Cellular Responses to Oxidative Damage: Cell Aging. The aim of this project is to identify the mechanisms by which oxidative stress and free radical damage cause cell aging. This work will make a significant contribution to our understanding of the aging process in cells by identifying the major reactive oxygen species that contribute to cell aging, which defence systems and antioxidants provide the greatest degree of protection, what damage accumulates as cells age and which genetic systems are activated as during the process.Read moreRead less
Regulation of mammalian heart development by transcription factors FHL2, GATA-4 & FOG-2. FHL2 is involved in many biological processes including intracellular signaling and gene transcription. GATA and FOG proteins are critical for the development of diverse tissues, including the heart. Knowledge gained in this project will advance our understanding of many cellular processes, including heart development, and will contribute to our knowledge in Biology, Zoology and Veterinary Science. More spe ....Regulation of mammalian heart development by transcription factors FHL2, GATA-4 & FOG-2. FHL2 is involved in many biological processes including intracellular signaling and gene transcription. GATA and FOG proteins are critical for the development of diverse tissues, including the heart. Knowledge gained in this project will advance our understanding of many cellular processes, including heart development, and will contribute to our knowledge in Biology, Zoology and Veterinary Science. More specifically, it will contribute to Stem Cell research, a 'hot' area in the biotechnology industry, particularly towards building a strong base of expertise, skills and technological capability in this new field, and may even lead to the development of a commercial product e.g. a heart muscle cell-coated biomaterial to aid failing heart.Read moreRead less