The regulation of signalling molecules in Saccharomyces Cerevisiae by inositol polyphosphate 5-phosphatases. Phosphoinositide signalling molecules regulate the actin cytoskeleton, secretion, vesicular trafficking and cell growth and death. We have identified, cloned and characterised a family of signal terminating enzymes called inositol polyphosphate 5-phosphatases (5-phosphatases) that regulate phosphoinositide signalling molecules. We have cloned and characterised four distinct 5-phosphatases ....The regulation of signalling molecules in Saccharomyces Cerevisiae by inositol polyphosphate 5-phosphatases. Phosphoinositide signalling molecules regulate the actin cytoskeleton, secretion, vesicular trafficking and cell growth and death. We have identified, cloned and characterised a family of signal terminating enzymes called inositol polyphosphate 5-phosphatases (5-phosphatases) that regulate phosphoinositide signalling molecules. We have cloned and characterised four distinct 5-phosphatases in the yeast Saccharomyces Cerevisiae and demonstrated by both deletion and overexpression studies that these enzymes regulate the actin cytoskeleton, endocytosis and secretion. This research proposal aims to investigate the signalling complexes the 5-phosphatases form with specific actin binding and or regulatory proteins, investigate the complex interactions of phosphoinositide lipid phosphatases and the roles they play in regulating secretion from the endoplasmic reticulum and finally characterize a novel 5-phosphatase that we have recently identified. Collectively the outcome of these studies will provide novel information about the functionallly significant signalling pathways regulated by this important enzyme family.Read moreRead less
The role of PtdIns(4,5)P2 in cellular responses in Saccharomyces cerevisiae. This grant application falls under the criteria of frontier technologies in genomics/phenomics and complex systems. We are characterizing a highly conserved network of signaling molecules regulated by complex large families of enzymes that regulate the bending of membranes, and cellular events including cell division in plants, yeast and mammalian cells. We have developed cutting edge novel technologies to localize sign ....The role of PtdIns(4,5)P2 in cellular responses in Saccharomyces cerevisiae. This grant application falls under the criteria of frontier technologies in genomics/phenomics and complex systems. We are characterizing a highly conserved network of signaling molecules regulated by complex large families of enzymes that regulate the bending of membranes, and cellular events including cell division in plants, yeast and mammalian cells. We have developed cutting edge novel technologies to localize signaling on specific intracellular membranes and visualise the role cellular lipids play in forming tubules in cells. This project will result in the presentation of Australian research at international forums and support the training of PhD students.Read moreRead less
Investigation of a Phagocytic Synapse in the Uptake of Apoptotic Cells. Rapid clearance of cells that die by apoptosis is crucial for embryonic development, tissue turnover, and after inflammatory events. Specialised phagocytes engulf the apoptotic cell corpses in a way that minimises inflammation and prevents autoimmunity. Genetic studies have identified the key evolutionary receptors involved, but the molecular basis of this phagocytosis is still poorly understood. We have developed, and seek ....Investigation of a Phagocytic Synapse in the Uptake of Apoptotic Cells. Rapid clearance of cells that die by apoptosis is crucial for embryonic development, tissue turnover, and after inflammatory events. Specialised phagocytes engulf the apoptotic cell corpses in a way that minimises inflammation and prevents autoimmunity. Genetic studies have identified the key evolutionary receptors involved, but the molecular basis of this phagocytosis is still poorly understood. We have developed, and seek to establish, an integrated model that incorporates new findings to explain how the distinctive functions of specialised receptors can be orchestrated to achieve this function. A successful outcome to the project will provide new knowledge of value to human health.Read moreRead less
Regulation of MHC-I and ICAM-1 by flavivirus, West Nile. This project investigates the intracellular signalling pathway responsible for the expression of genes which are critical to our immune response. We have demonstrated in a mouse model that high levels of expression of two of these genes in flavivirus encephalitis are associated with a survival advantage. We would expect this project to provide basic new information about the mechanisms of expression of these genes as well as information ab ....Regulation of MHC-I and ICAM-1 by flavivirus, West Nile. This project investigates the intracellular signalling pathway responsible for the expression of genes which are critical to our immune response. We have demonstrated in a mouse model that high levels of expression of two of these genes in flavivirus encephalitis are associated with a survival advantage. We would expect this project to provide basic new information about the mechanisms of expression of these genes as well as information about the interaction of this family of viruses, flavivirus with the host.Read moreRead less
Examination of the Calcium Signalling Dynamics Linked to Integrin Adhesion Utilising a Novel Micro-imaging System. This study aims at increasing our understanding of the fundamental cell processes that allow cells to adhere to surfaces. The proposed study will lead to a greater understanding of the calcium signalling mechanisms that are fundamental to diverse biological phenomena such as, tissue regeneration and repair, blood clotting, cancer metastasis, and neuronal cell function. From a preven ....Examination of the Calcium Signalling Dynamics Linked to Integrin Adhesion Utilising a Novel Micro-imaging System. This study aims at increasing our understanding of the fundamental cell processes that allow cells to adhere to surfaces. The proposed study will lead to a greater understanding of the calcium signalling mechanisms that are fundamental to diverse biological phenomena such as, tissue regeneration and repair, blood clotting, cancer metastasis, and neuronal cell function. From a preventative health perspective, the investigation of platelet calcium signalling will greatly accelerate the development of new pharmaceuticals to tackle acute and chronic cardiovascular diseases, such as stroke, heart attack and artherosclerosis. Read moreRead less
A novel role for the proteins Scribble & Dlg in the formation of cell protrusions and their effects on cell function. Dlg and Scribble are recently discovered proteins that are required during development, immune regulation, neural signalling and tumour suppression. Understanding how they work will enable the development of diagnostic and therapeutic tools that have the potential to influence an enormous range of diseases, from cancer to immunodeficiencies and autoimmune diseases. Researchers at ....A novel role for the proteins Scribble & Dlg in the formation of cell protrusions and their effects on cell function. Dlg and Scribble are recently discovered proteins that are required during development, immune regulation, neural signalling and tumour suppression. Understanding how they work will enable the development of diagnostic and therapeutic tools that have the potential to influence an enormous range of diseases, from cancer to immunodeficiencies and autoimmune diseases. Researchers at the PeterMac perform world-leading research into the biology of Scribble and Dlg, and their role in cancer biology and immune function. The mechanistic insight provided by this project will continue that tradition, and facilitate translation of our basic research into clinical applications in important disease areas.Read moreRead less
Lipid raft and cyotoskeleton organization: How membrane domains give cells direction. For a large number of cells in our body it is imperative that they are able to orientate themselves relative to their environment, sense direction and translate incoming signals. To do so it is hypothesised that lipids on the cell surface are redistributed to form specialized domains. An asymmetric distribution of membrane domains can provide cells with a front and rear end and can further concentrate and co-or ....Lipid raft and cyotoskeleton organization: How membrane domains give cells direction. For a large number of cells in our body it is imperative that they are able to orientate themselves relative to their environment, sense direction and translate incoming signals. To do so it is hypothesised that lipids on the cell surface are redistributed to form specialized domains. An asymmetric distribution of membrane domains can provide cells with a front and rear end and can further concentrate and co-ordinate signalling molecules to a specific site. The project will determine the role of lipid domain in stabilizing cell shape and their remodelling during cell migration, the digestion of foreign particles and the formation of cell-cell contacts.Read moreRead less
Myofibroblast differentiation: from haemopoietic cells to smooth muscle. Until very recently the ability of adult cells with specific differentiated functions to re-differentiate for another function was thought to be extremely limited. However we have shown that cells ultimately derived from the bone marrow can differentiate into fibroblasts, then into myofibroblasts and then into smooth muscle cells. This project will build on these unique findings and determine the molecular mechanisms cont ....Myofibroblast differentiation: from haemopoietic cells to smooth muscle. Until very recently the ability of adult cells with specific differentiated functions to re-differentiate for another function was thought to be extremely limited. However we have shown that cells ultimately derived from the bone marrow can differentiate into fibroblasts, then into myofibroblasts and then into smooth muscle cells. This project will build on these unique findings and determine the molecular mechanisms controlling this process. We hypothesise that the local environment of a cell is critical and will involve a combination of particular extracellular matrix and growth factors as well as mechanical tension and the presence of other cell types.Read moreRead less
Combined genetic and cellular analysis of melanisation to study variation in human pigmentation. This investigation examines variations in the genes that are important determinants of human skin pigmentation and are likely to be associated with skin cancer risk. Our research program will form the basis of future diagnostics based on major genes that determine a persons skin type. Current skin cancer prevention strategies rely predominantly on broad spectrum campaigns that are aimed at increasi ....Combined genetic and cellular analysis of melanisation to study variation in human pigmentation. This investigation examines variations in the genes that are important determinants of human skin pigmentation and are likely to be associated with skin cancer risk. Our research program will form the basis of future diagnostics based on major genes that determine a persons skin type. Current skin cancer prevention strategies rely predominantly on broad spectrum campaigns that are aimed at increasing the general community awareness of the damaging effects of UV radiation. A better understanding of the genetic basis of UV-sensitive skin types will greatly enhance the targeting of such skin cancer-prevention campaigns, provide an understanding of changes that occur in skin pathology, and the mechanisms of sun induced tanning.Read moreRead less
Parallel genetic and cellular analysis of melanogensis: A new paradigm to study variation in pigmentation. This is the first attempt to characterise the differences in human pigmentation using a combined genetic and cellular analysis of melanogenesis. We have the ability to culture the pigmenting cells of the human epidermis and hair follicles called melanocytes from individuals of defined genotype. This will allow us to correlate mutations in melanosomal proteins with functional defects withi ....Parallel genetic and cellular analysis of melanogensis: A new paradigm to study variation in pigmentation. This is the first attempt to characterise the differences in human pigmentation using a combined genetic and cellular analysis of melanogenesis. We have the ability to culture the pigmenting cells of the human epidermis and hair follicles called melanocytes from individuals of defined genotype. This will allow us to correlate mutations in melanosomal proteins with functional defects within the cells in culture using live cell imaging, electron microscopy and biochemical analysis. This will provide a molecular basis to explain the pigmentary characteristics of individuals allowing prediction and diagnosis of their photosensitivity with important implications for skin cancer risk.Read moreRead less