Regulation Of PtdIns(3,4,5)P3 By Inositol Polyphosphate 5-phosphatases
Funder
National Health and Medical Research Council
Funding Amount
$200,880.00
Summary
Growing cells respond to growth factors by dividing and proliferating. Uncontrolled cell growth leads to cancer. Signals are released from the cell membrane following growth factor stimulation, that communicate via a complex network of intracellular signalling molecules, that instruct the nucleus to divide. One critical signalling network that mediates cell growth are the phosphoinositide messenger molecules. These signals are switched off by a family of proteins called inositol polyphosphate 5- ....Growing cells respond to growth factors by dividing and proliferating. Uncontrolled cell growth leads to cancer. Signals are released from the cell membrane following growth factor stimulation, that communicate via a complex network of intracellular signalling molecules, that instruct the nucleus to divide. One critical signalling network that mediates cell growth are the phosphoinositide messenger molecules. These signals are switched off by a family of proteins called inositol polyphosphate 5-phosphatases. We propose the 5-phosphatases are essential for normal cell growth. Several studies have suggested in their absence tumour formation may occurr. We have identified a new member of this enzyme family called SHIP-2. This proposal aims to investigate the mechanisms by which this enzyme family metabolises signalling molecules and thereby regulates cell growth. We will also characterize how the 5-phosphatases control the normal pathways by which primitive cells differeniate into mature cells.Read moreRead less
Post-genomic investigation of the relict plastid and mitochondrion of malaria parasites. Malaria is a major global health problem. The malaria parasite has two substructures, a relict chloroplast and a mitochondrion, that are excellent targets for new and existing drugs. However, we do not know the key functions of these two compartments. The entire genetic blueprint (genome) is now available for the malaria parasite and I propose to determine exactly which parts of the genome service the rel ....Post-genomic investigation of the relict plastid and mitochondrion of malaria parasites. Malaria is a major global health problem. The malaria parasite has two substructures, a relict chloroplast and a mitochondrion, that are excellent targets for new and existing drugs. However, we do not know the key functions of these two compartments. The entire genetic blueprint (genome) is now available for the malaria parasite and I propose to determine exactly which parts of the genome service the relict chloroplast and mitochondria. This will sketch out a picture of their inner workings. Armed with this information we can take a rational approach to seeking an Achilles? Heel of malaria against which parasite-specific drugs can be developed.Read moreRead less
Inhibition of pro-inflammatory cytokine secretion- A new route to therapeutics of chronic inflammatory disease. Chronic inflammatory diseases, including rheumatoid arthritis and inflammatory bowel disease, affect millions of people leading to considerable suffering, economic loss and premature death. Anti-TNF treatments have recently shown success in the treatment of rheumatoid arthritis, inflammatory bowel disease and other conditions, however, a substantial number of patients (~50%) do not re ....Inhibition of pro-inflammatory cytokine secretion- A new route to therapeutics of chronic inflammatory disease. Chronic inflammatory diseases, including rheumatoid arthritis and inflammatory bowel disease, affect millions of people leading to considerable suffering, economic loss and premature death. Anti-TNF treatments have recently shown success in the treatment of rheumatoid arthritis, inflammatory bowel disease and other conditions, however, a substantial number of patients (~50%) do not respond to the current TNF treatments. Improved anti-TNF strategies would provide enhanced health outcomes and welcome relief to many Australians. In addition, the economic benefit of the TNF market is very substantial. Therefore the potential impact of this research is very high both for health care and economical potential.Read moreRead less
Shaping a signal: studies on non-contiguous residues in an intracellular serpin that constitute a novel nuclear protein import signal. Eukaryotic cells contain membrane-bound organelles like the nucleus, endoplasmic reticulum and mitochondria, and use specific mechanisms to direct proteins from their site of synthesis to their target organelle. In nuclear proteins, sequence motifs termed nuclear localization signals (NLSs) direct engagement with the nuclear pore complex and translocation from cy ....Shaping a signal: studies on non-contiguous residues in an intracellular serpin that constitute a novel nuclear protein import signal. Eukaryotic cells contain membrane-bound organelles like the nucleus, endoplasmic reticulum and mitochondria, and use specific mechanisms to direct proteins from their site of synthesis to their target organelle. In nuclear proteins, sequence motifs termed nuclear localization signals (NLSs) direct engagement with the nuclear pore complex and translocation from cytoplasm to nucleus. All NLSs described so far consist of 5-7 contiguous basic residues. We propose to study a novel NLS that we recently discovered on an intracellular serpin. This comprises non-contiguous residues that together form a basic "patch" on the mature protein, and is the first example of a conformational NLS.Read moreRead less
Functional Characterisation Of N4WBP5 And N4WBP5A, Novel Nedd4-interacting Proteins
Funder
National Health and Medical Research Council
Funding Amount
$480,750.00
Summary
The proteins that make up a cell must be correctly localised in order to perform their normal function. Specialised cellular activities are carried out in distinct compartments within a cell and proteins must correctly localise in them and traffic between them. Intracellular protein trafficking is a highly regulated process involving many components. Recent findings have shown that intracellular trafficking is regulated in many cases by distinct protein modifications. One such modification is ta ....The proteins that make up a cell must be correctly localised in order to perform their normal function. Specialised cellular activities are carried out in distinct compartments within a cell and proteins must correctly localise in them and traffic between them. Intracellular protein trafficking is a highly regulated process involving many components. Recent findings have shown that intracellular trafficking is regulated in many cases by distinct protein modifications. One such modification is tagging of a small protein called ubiquitin to proteins that are being trafficked. A focus of research in our laboratory is the study of a protein, called Nedd4, which directly tags proteins with ubiquitin. We have recently identified two novel proteins that interact with Nedd4 and localise to distinct subcellular compartments that are sites for the correct sorting and delivery of proteins trafficking within the cell. The main aim of our proposal is to characterise how these proteins function. We propose that these proteins are involved in intracellular trafficking and that they may function by targeting Nedd4 to the cellular trafficking machinery. This may be required for Nedd4 to tag molecules with ubiquitin that are involved in intracellular trafficking. Our experiments will test the functional relationship between Nedd4 and the novel proteins and determine the particular trafficking pathways in which these proteins are involved. Defects in cellular processes regulated by Nedd4 and other similar proteins cause a number of human diseases including an inherited form of hypertension and a specific group of cancers. In addition, a large number of human diseases result directly from defects which disrupt intracellular trafficking pathways. The results of this study will provide further insight into this essential cellular process and may ultimately contribute to the development of therapies for diseases resulting from defects in intracellular trafficking.Read moreRead less
The Molecular Basis of Copper Metabolism in Sheep. The unusual copper metabolism of sheep represents a significant agricultural problem. They are very susceptible to copper deficiency, but readily accumulate copper to toxic levels in the liver leading to fatal liver failure. We propose to elucidate the reason for the copper accumulation phenotype of sheep. We are focussing on WND, a copper transporter responsible for copper excretion into bile. We discovered a novel form of sheep WND designated ....The Molecular Basis of Copper Metabolism in Sheep. The unusual copper metabolism of sheep represents a significant agricultural problem. They are very susceptible to copper deficiency, but readily accumulate copper to toxic levels in the liver leading to fatal liver failure. We propose to elucidate the reason for the copper accumulation phenotype of sheep. We are focussing on WND, a copper transporter responsible for copper excretion into bile. We discovered a novel form of sheep WND designated WNDb to distinguish it from the normal form, WNDa. The experiments outlined are designed to understand the function of both proteins in the sheep and their role in copper sequestration.Read moreRead less
Inside our cells is a complex traffic system. The vehicles are vesicles that come in different shapes and sizes and travel to specific destinations in the cell to deliver cargo such as: surface growth factor receptors that are to have their signalling terminated, proteins and lipids destined for the cell wall for growth or development (like neurite outgrowth) and proteins and hormones destined for secretion (like neurotransmitter release). More than 100 human genetic disorders map to defects in ....Inside our cells is a complex traffic system. The vehicles are vesicles that come in different shapes and sizes and travel to specific destinations in the cell to deliver cargo such as: surface growth factor receptors that are to have their signalling terminated, proteins and lipids destined for the cell wall for growth or development (like neurite outgrowth) and proteins and hormones destined for secretion (like neurotransmitter release). More than 100 human genetic disorders map to defects in one of the components of this system. Proteins called small GTPases provide order for this traffic and allow specific cargo to reach specific destinations. They regulate cell functions by acting as switches, turning biochemical processes on and off inside the cell. Ral is a small GTPase enzyme found in brain and broadly distributed in other cells. We have discovered that Ral is part of a large signalling complex. When activated Ral stimulates effectors, either the exocyst or RalBP1. In turn, mild oxidative stress controls a Ral inhibitor protein called ERp57. The research proposed aims to establish the functional role for the Ral signalling complex in cells. We will determine with which vesicle trafficking events Ral is associated, which effector it utilises in that pathway, and how that effector directs the traffic. We will also map the steps that may lead to inactivation of Ral via ERp57 in cells, and propose that this is mediated by mild oxidative stress. Techniques of molecular biology, biochemistry, molecular biology, proteomics and microscopy will be used to establish these functions. The research will lead to increased knowledge of the significance of this protein to cellular and particularly neuronal cell function. This forms the basis for understanding normal cell function and for identification of further factors causing diseases of vesicle transport. In time, such research aids in the development of specific therapies for sufferers of such diseases.Read moreRead less
Structural Studies Of The Jak And Abl Kinases: A Prerequisite For Drug Design
Funder
National Health and Medical Research Council
Funding Amount
$360,965.00
Summary
Protein tyrosine kinases (PTK) are a large, pivotal family of signalling molecules implicated in diseases such as cancer and immune related disorders. This fellowship aims to develop more potent kinase inhibitors of a number of PTKs using Cytopia’s drug discovery capability coupled with the X-ray crystallography expertise within Monash University. This innovative approach will permit a rational structure-based drug discovery platform to be established and will lead to the creation of a portfolio ....Protein tyrosine kinases (PTK) are a large, pivotal family of signalling molecules implicated in diseases such as cancer and immune related disorders. This fellowship aims to develop more potent kinase inhibitors of a number of PTKs using Cytopia’s drug discovery capability coupled with the X-ray crystallography expertise within Monash University. This innovative approach will permit a rational structure-based drug discovery platform to be established and will lead to the creation of a portfolio of phase I therapeutics, which will be of substantial benefit in the medical health area.Read moreRead less
Development Of BRET Detection Systems: Tools For Functional Proteomics And Drug Discovery
Funder
National Health and Medical Research Council
Funding Amount
$376,320.00
Summary
The internal structure of articular cartilage is critical to its biomechanical function. Cartilage is one of the most intricate and difficult tissues to examine in-vivo. Maintenance of its functional characteristics depends heavily of the internal microstructure of the tissue, while conventional arthroscopy can only give a view of the surface and provides no information on the internal structure. Biopsy examination can also destroy the integrity of the tissue, making it impossible to concurrentl ....The internal structure of articular cartilage is critical to its biomechanical function. Cartilage is one of the most intricate and difficult tissues to examine in-vivo. Maintenance of its functional characteristics depends heavily of the internal microstructure of the tissue, while conventional arthroscopy can only give a view of the surface and provides no information on the internal structure. Biopsy examination can also destroy the integrity of the tissue, making it impossible to concurrently examine the structure and function of the tissue. The structure-function relationship is thus critical to the study and the advancement of clinical treatment techniques for cartilage disorders. Osteoarthritis is characterized by severe disruption to the cartilage matrix. The emergence of autologous chondrocyte implant (ACI) therapy as a method for repairing cartilage defects has further increased interest in clinical techniques for the examination of cartilage structure and function. The development of confocal microscopy facilitates internal examination of loaded tissue for the first time, enabling direct examination of the association between structure and function of the tissue. A prototype confocal arthroscope has been developed to facilitate clinical examination of cartilage structure. This, in turn, allows the functional characteristics of the tissue to be deduced. Cartilage exhibits little intrinsic repair making biopsies undesirable. Thus, with respect to cartilage in particular, the developed technologies promise to enable examination to a level of detail which was previously impossible. The current prototype arthroscope has demonstrated the feasibility of a genuine clinical instrument. This grant application seeks funds to conduct initial clinical trials in order to gain sufficient practical feedback to enable design and construction of a clinically ready system.Read moreRead less