All cells in the blood are the descendants of a single cell type, the stem cell. Stem cells are found in the bone marrow and throughout life have the unique ability to generate more of themselves (termed self-renewal) as well as to produce the functional cell types of the blood, ie. red and white blood cells. This project concentrates on the processes by which these stem cells can achieve these two functions. What are the genes that enable a stem cell to have this self-renewal characteristic and ....All cells in the blood are the descendants of a single cell type, the stem cell. Stem cells are found in the bone marrow and throughout life have the unique ability to generate more of themselves (termed self-renewal) as well as to produce the functional cell types of the blood, ie. red and white blood cells. This project concentrates on the processes by which these stem cells can achieve these two functions. What are the genes that enable a stem cell to have this self-renewal characteristic and conversely what are the genes that are activated when a cell becomes committed to become, for example, a white blood cell ? We have identified a gene, Pax5, which is essential in the process whereby a stem cell commits to become a lymphocyte . Our aim is to understand the function of Pax5 as a model for understanding how the commitment process as a whole works in the blood. These studies, as well as having an underlying fundamental scientific importance, are relevant to the clinical development of a number of stem cell therapies which rely on boosting stem cell production in procedures such as bone marrow transplantation for leukaemia and immune deficiency. In addition a number of characterised human blood malignancies indicate that inappropriate lineage commitment may be a factor in cancer.Read moreRead less
Epigenetic Silencing Of Retroelements In Mammalian Stem Cells: A Role For RNA Interference?
Funder
National Health and Medical Research Council
Funding Amount
$296,980.00
Summary
Now that the human genome has been sequenced, all the genes which encode the bricks and mortar of our cells have been defined. A major question remains: how are all these genes controlled and co-ordinated? What turns them on or off at precisely the right time? In this project we wish to test whether a newly-discovered mechanism of turning genes off in plants and flies also works in mammals. If we demonstrate this mechanism then it may help us to improve gene therapy - a novel form of medical tre ....Now that the human genome has been sequenced, all the genes which encode the bricks and mortar of our cells have been defined. A major question remains: how are all these genes controlled and co-ordinated? What turns them on or off at precisely the right time? In this project we wish to test whether a newly-discovered mechanism of turning genes off in plants and flies also works in mammals. If we demonstrate this mechanism then it may help us to improve gene therapy - a novel form of medical treatment in which healthy genes are used to replace defective genes in cells. Both inherited diseases, like hemophilia, and acquired diseases, like cancer, have been considered appropriate targets for gene therapies. Surprisingly, however, the promises of gene therapy have not kept up with expectations. In attempting to achieve clinically relevant results, viruses (masters of forcing infected cells to do their bidding) have been harnessed to deliver healthy genes into diseased cells. A major problem has been that the modified, safe viruses used clinically have not been efficient at achieving sustained production of healthy gene products. In examining the question of what turns gene off, we will attack the problem of sustainability of gene therapy by defining the mechanisms involved in switching gene therapy viruses off. If we can understand what switches viral genes off in cells, then we should be able to devise means to avoid the 'off switch' and thereby provide durable treatments for many types of cancer. In the studies described , we will attack this problem using a number of different, but complementary approaches.Read moreRead less
Regulation Of Adult Colonic Crypt Homeostasis And Activation Of Colon Cancer Metastasis Genes By C-Myb
Funder
National Health and Medical Research Council
Funding Amount
$666,116.00
Summary
Regulation of normal colon biology and activation of genes involved colon cancer The c-myb gene is essential for the normal biology of the blood system and the colon. This gene is involved in regulating the balance between the production of new cells and their timely removal once they have completed their assigned tasks. There is a large body of evidence that supports the role of c-myb in the regulation of the blood system. We believe that the rules that govern the production of the huge number ....Regulation of normal colon biology and activation of genes involved colon cancer The c-myb gene is essential for the normal biology of the blood system and the colon. This gene is involved in regulating the balance between the production of new cells and their timely removal once they have completed their assigned tasks. There is a large body of evidence that supports the role of c-myb in the regulation of the blood system. We believe that the rules that govern the production of the huge number of cells needed to have a healthy blood system are similar if not identical to the rules used by the colon. This is because the colon also produces a massive number of cells each with special tasks and a defined life span of a few days. It is this rapid expansion of cell numbers and the programmed short life span of cells that necessitates multiple controls and very tight regulation. Furthermore if this process is hijacked by genetic changes that undermine these controls then there are numerous opportunities to initiate and potentiate malignant change or cancer. This project examines the role of the same genes in two contexts. Firstly when the genes are expressed at normal, highly regulated levels associated with the normal biology of the colon. The second context is when these genes are permitted to be over-expressed and thus drive processes for longer or in inappropriate situations leading to malignant growth.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
CesA (cellulose synthase) genes of Arabidopsis; all doing the same job or specialists cooperating to make the most abundant biopolymer. The biosphere makes more cellulose than any other polymer with fibre industries depending on its physical properties and atmospheric carbon dioxide levels depending on its stability as a carbon sink. Demonstrations that cellulose production needs CesA genes drove recent progress in elucidating the mechanism of synthesis. CesA proteins all look very similar but i ....CesA (cellulose synthase) genes of Arabidopsis; all doing the same job or specialists cooperating to make the most abundant biopolymer. The biosphere makes more cellulose than any other polymer with fibre industries depending on its physical properties and atmospheric carbon dioxide levels depending on its stability as a carbon sink. Demonstrations that cellulose production needs CesA genes drove recent progress in elucidating the mechanism of synthesis. CesA proteins all look very similar but if all do the same job, why do plants need so many and why do none seem redundant? We will make gene interchanges in transgenic plants, build chimeric genes and identify where each CesA protein operates. This will identify their individual and cooperative contributions to cellulose production.Read moreRead less
Function of a new splicing factor, RBM4. New genomic knowledge is revolutionizing our world. However our understanding of the basic mechanisms of RNA maturation, especially regulation of splicing lags significantly behind our understanding of related genomic processes. This project is a genetic approach to help elucidate the function of new splicing factors and characterize the way in which specific RNA sequences are recognized. It should promote the better understanding of regulatory events inv ....Function of a new splicing factor, RBM4. New genomic knowledge is revolutionizing our world. However our understanding of the basic mechanisms of RNA maturation, especially regulation of splicing lags significantly behind our understanding of related genomic processes. This project is a genetic approach to help elucidate the function of new splicing factors and characterize the way in which specific RNA sequences are recognized. It should promote the better understanding of regulatory events involved in controlling gene expression during development and differentiation. Results from this project will also provide new insights into the 'multifunctionality' of cellular proteins and will illustrate the importance of RNA studies in molecular medicine.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
Proteomic and Transcriptional Profiling of Cartilage. Gene expression and signalling pathways that regulate cartilage formation, and its orderly transition to bone, are poorly described. Our studies will, for the first time, combine two complementary cutting-edge approaches, protein identification by proteomic analysis, and mRNA profiling by microarray analysis, to define these pathways and develop a comprehensive catalogue of proteins and gene expression patterns during cartilage development a ....Proteomic and Transcriptional Profiling of Cartilage. Gene expression and signalling pathways that regulate cartilage formation, and its orderly transition to bone, are poorly described. Our studies will, for the first time, combine two complementary cutting-edge approaches, protein identification by proteomic analysis, and mRNA profiling by microarray analysis, to define these pathways and develop a comprehensive catalogue of proteins and gene expression patterns during cartilage development and bone formation. This information will provide insight into the regulation of cartilage differentiation, maturation and structure, and will provide a critical platform for the development of more sophisticated cartilage and bone biomaterials for improved tissue repair and regeneration.Read moreRead less
This is a study of the biological system of epigenetics. Every cell in our body has the same genetics, or library of information contained in the form of DNA sequence. Epigenetics is the system that controls how this DNA is used in a particular situation, or what books are opened and read. During embryonic development, cells know what they want to become, e.g., a muscle cell, and, once they take on an identity, remember that they are when they duplicate themselves during growth. Epigenetics does ....This is a study of the biological system of epigenetics. Every cell in our body has the same genetics, or library of information contained in the form of DNA sequence. Epigenetics is the system that controls how this DNA is used in a particular situation, or what books are opened and read. During embryonic development, cells know what they want to become, e.g., a muscle cell, and, once they take on an identity, remember that they are when they duplicate themselves during growth. Epigenetics does not achieve this through changing genetics the library always stays intact. Rather, it acts by using proteins or chemicals to make DNA functional in one way, or another. Genomic imprinting is a special type of epigenetics. While an embryo has received identical genetic information from each of its parents, the epigenetic information received from each parent was not entirely the same. Some genes which behave differently according to what parent they came from. For example, a gene that makes a growth factor protein is active only if received from the father. If received from the mother, it is inactive, and makes no protein. Genes behaving in this way are known as imprinted genes. We are trying to discover what epigenetic mechanisms are behind this behaviour of imprinted genes. One way we are approaching this problem is to study germ cells the cells giving rise to eggs and sperm. These cells are unusual in that their imprinted genes behave in the same way regardless of whether they were received from the mother or father, i.e., like any other gene. If we can understand why this is the case, we will be better able to understand why imprinted genes behave the way they do in the rest of the cells of the body. Broadly, the mechanisms we uncover should further our understanding of germ cell development, gene expression, and disease. Perturbations in the epigenetic profile are likely causes of human disease, including cancer.Read moreRead less