Approaches to combat AIDS and its causative agent, the human immunodeficiency virus HIV-1, have thus far proved ineffective. The proposed research program intends to investigate the nuclear import of two HIV-1 proteins which have central roles in HIV infection. We will apply our expertise in the area of the regulation of nuclear import of viral proteins, and build on our observations with respect to these proteins to attempt to establish the mechanistic basis of their nuclear import, and how thi ....Approaches to combat AIDS and its causative agent, the human immunodeficiency virus HIV-1, have thus far proved ineffective. The proposed research program intends to investigate the nuclear import of two HIV-1 proteins which have central roles in HIV infection. We will apply our expertise in the area of the regulation of nuclear import of viral proteins, and build on our observations with respect to these proteins to attempt to establish the mechanistic basis of their nuclear import, and how this differs from the conventional nuclear import pathways used by normal cellular proteins. We already have evidence that nuclear import of HIV-Tat is regulated in novel fashion by cellular factors, and intend, through determining its mechanistic basis, to be able to form the basis of a strategy to block this import pathway specifically, and thereby inhibit HIV replication. This may form the basis in the future of a new pharmaceutical approach to combat HIV-AIDS.Read moreRead less
Inhibition Of Nef-activated Src-family Kinases By CHK
Funder
National Health and Medical Research Council
Funding Amount
$514,307.00
Summary
HIV hijacks infected blood cells to produce its own proteins. Nef is one of these proteins and Nef alone is sufficient to cause an AIDS-like disease. Recently, we discovered that a protein called CHK can inhibit Nef. Our research will determine how CHK inhibits Nef and test the feasibility of drugs based on CHK. Such drugs would slow AIDS progression, assisting conventional therapies and patients' immune systems to combat the infection, leading to longer, healthier, more productive lives.
The project aims to understand how a factor responsible for the production of a type of white blood cell interacts with its receptor. If we knew the molecular details of how this factor works then we would be able to control better diseases, such as osteoporosis and arthritis, where such cells can play havoc by destroying tissue. The project also has implications for certain leukaemias which lose growth control mechanisms in response to this factor.
The Interactions Of Dengue Virus RNA Dependent RNA Polymerase (NS5) With Other Viral And Host Factors.
Funder
National Health and Medical Research Council
Funding Amount
$170,165.00
Summary
Dengue fever is a mosquito-borne disease that is prevalent in tropical countries. It is estimated that 40% of the global population is at risk of dengue infection. Classical dengue fever is not life threatening. However, the more serious disease, dengue haemorrhagic fever-shock syndrome requires intensive medical attention to prevent fatality. A significant number of deaths are recorded each year especially in the underdeveloped countries. Dengue is periodically also a problem in northern Austra ....Dengue fever is a mosquito-borne disease that is prevalent in tropical countries. It is estimated that 40% of the global population is at risk of dengue infection. Classical dengue fever is not life threatening. However, the more serious disease, dengue haemorrhagic fever-shock syndrome requires intensive medical attention to prevent fatality. A significant number of deaths are recorded each year especially in the underdeveloped countries. Dengue is periodically also a problem in northern Australia. There is no cure for dengue fever. The present research aims to use a knowledge-based approach to develop novel antiviral strategies based on preventing the critical protein interactions required for the normal virus life cycle. Two of the most important proteins involved in dengue virus replication are called the NS3 and NS5 proteins. The protein-protein interaction (contact) that occurs between NS5 and NS3 is crucial for the replication of the virus. Little is known about this interaction at present, and the studies we propose will directly address this issue. We have previously shown that a 37 amino acid in the middle of NS5 contains a nuclear localisation signal that can target the normally cytoplasmic protein to the nucleus of the infected cell. What the function of this protein is in the nucleus is not known. We will use a technique called the yeast two-hybrid test to address the question of dengue virus protein interactions in the common bakers yeast. This method is very sensitive and powerful and will provide important insights that will contribute to the development of a rapid high-throughput test to screen the extensive extract collection from Australia's marine biodiversity, held by the Australian Institute of Marine Sciences, to discover suitable inhibitors of NS3-NS5 interaction.Read moreRead less
The Structural Basis Of Ligand-Induced Activation Of The Insulin Receptor
Funder
National Health and Medical Research Council
Funding Amount
$640,825.00
Summary
We aim to understand how insulin binds to and activates its cell-surface receptor. This information has implications for the design of anti-diabetic agents targetted directly to the insulin receptor. Diabetes is a global health problem and is classified by the World Health Organization as an epidemic. The results also have implications for the insulin-like growth factor receptor system and the design of anti-cancer therapeutics directed towards it .
The Role Of Plasma Membrane Microdomains In Regulating Ras-dependent Raf Activation
Funder
National Health and Medical Research Council
Funding Amount
$216,100.00
Summary
In human cancers one or more of the signaling pathways leading from growth factor receptors at the cell surface to the nucleus where cell division is initiated are subverted. For example, a protein called Ras, that regulates a series of major signaling pathways, is mutated in 25% of all human tumours. This leaves Ras and the signaling pathways permanently switched on causing uncontrolled cell proliferation. Our previous work has demonstrated that Ras must be attached to the inner surface of the ....In human cancers one or more of the signaling pathways leading from growth factor receptors at the cell surface to the nucleus where cell division is initiated are subverted. For example, a protein called Ras, that regulates a series of major signaling pathways, is mutated in 25% of all human tumours. This leaves Ras and the signaling pathways permanently switched on causing uncontrolled cell proliferation. Our previous work has demonstrated that Ras must be attached to the inner surface of the cell membrane in order to function properly. This project now seeks to understand exactly how Ras attaches to and interacts with specific sites in the plasma membrane. Its is becoming clear that different isoforms of Ras, called H-, N- and K-ras have different functions in the cell which may in turn result from their different sites of attachment to the cell membrane. This is important because by understanding the precise micro-environment in which the different Ras proteins operate and how they activate subsequent proteins in their signaling networks we will be in a good position to design drugs that selectively compromise the function of each specific Ras isoform. A highly relevant example is provided by K-ras which is mutated in 90% of all pancreatic cancers and 50% of all colon cancers. Clearly the clinical impact of a drug that could selectively neutralise K-Ras function in these tumours is potentially enormous.Read moreRead less
Role Of PAK1 In Colorectal Cancer Growth And Metastasis Regulated By Gastrins
Funder
National Health and Medical Research Council
Funding Amount
$460,070.00
Summary
Increased level of PAK1(a protein kinase) was associated with the progression of colorectal (large bowel) cancer (CRC). Gastrin peptides are growth factors responsible for CRC development. The objective of this project is to determine the role of PAK1 in the regulation of CRC growth and metastasis by gastrin peptides. We will use cell culture, animal models and clinical samples in the program. A successful outcome will lead to the development of new CRC therapies such as inhibitors of PAK1.
Understanding The Role Of Tec In Fcgamma Receptor Mediated Phagocytosis
Funder
National Health and Medical Research Council
Funding Amount
$211,527.00
Summary
The recognition and destruction of bacterial pathogens and other foreign particles by specific immune cells (macrophages) is principally mediated by the Fcgamma class of cell surface antibody receptors. This proposal aims to understand the molecular mechanisms which link receptor activation to the cellular rearrangements required to invaginate or swallow the offending particle. We have used immunofluorescent microscopy and biochemical methods to show that the intracellular tyrosine kinase Tec is ....The recognition and destruction of bacterial pathogens and other foreign particles by specific immune cells (macrophages) is principally mediated by the Fcgamma class of cell surface antibody receptors. This proposal aims to understand the molecular mechanisms which link receptor activation to the cellular rearrangements required to invaginate or swallow the offending particle. We have used immunofluorescent microscopy and biochemical methods to show that the intracellular tyrosine kinase Tec is an important component of the phagocytosis mechanism. Here we plan to use highly selective gene targeting methods to generate a mouse cell culture model system which is devoid of Tec protein. This will allow us to determine whether Tec is essential for Fcgamma-mediated phagocytosis. Reintroduction of mutant versions of the Tec protein into this null background will provide detailed information on the molecular partners of Tec and the individual roles of the various domains within the Tec protein. By studying the molecular mechanism of phagocytosis, we expect to gain an understanding of how to influence the Fcgamma signalling pathway, either to enhance the ability to deal with pathogens, or to restrict the consequences of excessive phagocytosis associated with autoimmune diseases. Tec is an enzyme likely to play an important role between the Fcgamma receptor and actin cytoskeleton rearrangements and therefore is a potentially important drug target.Read moreRead less