Mechanism Of Action Of Sec1p-like Proteins In Membrane Trafficking
Funder
National Health and Medical Research Council
Funding Amount
$234,936.00
Summary
One of the most important evolutionary changes that has occurred is the development of intracellular compartments. All eukaryotic cells possess numerous membrane-encased structures which provide the basis for intracellular specialisation. For example, in order to degrade unwanted components cells have developed degradative enzymes. It is vital for the cell that these enzymes are sequestered away from other cellular components to avoid destruction of valuable molecules. In addition, the cell has ....One of the most important evolutionary changes that has occurred is the development of intracellular compartments. All eukaryotic cells possess numerous membrane-encased structures which provide the basis for intracellular specialisation. For example, in order to degrade unwanted components cells have developed degradative enzymes. It is vital for the cell that these enzymes are sequestered away from other cellular components to avoid destruction of valuable molecules. In addition, the cell has developed a complex assembly line of modifications that are added to proteins in a specific order as they travel to their final destination within the cell. This necessitates the accurate passage of molecules between compartments, a process known as vesicle transport. To orchestrate the complex network of vesicular transport steps between all of the various intracellular compartments it is necessary to employ complex machinery to guide and check that these steps occur with high fidelity. The goal of our research proposal is to define the function of one of the molecules involved in this control process, the so-called Sec1p proteins. The strength of our proposal lies in the diversity of our approach. We intend to explore the molecular advantages of a relatively simple eukaryotic organism, a yeast cell, and apply the findings obtained from this cell to a more complex but highly related vesicular transport process; that of the insulin-regulated movement of a glucose transporter in mammalian fat and muscle cells. While we intend to apply our findings to the treatment of patients with diabetes, it is our ultimate goal to be able to learn more about this fundamental cell biological process so that we can apply our knowledge to understanding many different disease states.Read moreRead less
Signalling Networks As Targets For Antibody Therapy In Glioma.
Funder
National Health and Medical Research Council
Funding Amount
$526,683.00
Summary
Antibodies are a major component of the bodies immune system that bind (i.e. stick) to foreign substances such as viruses. Once bound, these antibodies can activate other parts of the immune system, which help destroy the foreign substance. Analogous to the situation above, a number of institutions are testing antibodies that bind to cancer cells, in order to determine if they are able to destroy these cells. It is also possible to generate antibodies that bind to receptors on the surface of can ....Antibodies are a major component of the bodies immune system that bind (i.e. stick) to foreign substances such as viruses. Once bound, these antibodies can activate other parts of the immune system, which help destroy the foreign substance. Analogous to the situation above, a number of institutions are testing antibodies that bind to cancer cells, in order to determine if they are able to destroy these cells. It is also possible to generate antibodies that bind to receptors on the surface of cancer cells and block their function. If you target a receptor critical to the growth or survival of a cancer cell in this way, then swtiching-off this signal may inhibit tumor growth. In this proposal we plan to test a panel antibodies that recognize receptors important to the growth of brain cancer. Two of these antibodies have been generated and the other two will be made as part of this proposal. A key aspect of this proposal will be testing these antibodies in combination to determine how many receptors need to be targeted in order to get complete tumor regressions in animal models. Overall this work will help us identify new therapeutic strategies for the treatment of brain cancer. Finally, we will also analyze the way different receptors interact together in brain cancer cells.Read moreRead less
Molecular Mechanisms Of Receptor Activation And Signalling
Funder
National Health and Medical Research Council
Funding Amount
$571,980.00
Summary
Fundamental to our ability to respond to both immediate and long-term environmental changes and stresses is the coordinated regulation of cellular functions by hormonal and neurotransmitter stimuli. The great majority of such stimuli are sensed by G-protein coupled receptors (GPCR), complex glycoprotein molecules on the surface of most cells that selectively bind and are activated by various hormones and neurotransmitters. Although GPCRs are a superfamily of proteins that now compromise several ....Fundamental to our ability to respond to both immediate and long-term environmental changes and stresses is the coordinated regulation of cellular functions by hormonal and neurotransmitter stimuli. The great majority of such stimuli are sensed by G-protein coupled receptors (GPCR), complex glycoprotein molecules on the surface of most cells that selectively bind and are activated by various hormones and neurotransmitters. Although GPCRs are a superfamily of proteins that now compromise several hundred distinct but structurally-related members, the molecular mechanisms involved in their activation and, thus, their regulation of vital cellular functions, remains unclear. Based on insights that we have gained from the development and characterisation of several alpha1-adrenergic receptor mutants, we have developed a model of receptor activation. In this application we are proposing to further test and to extend the hypotheses underlying this model. Importantly, the functions regulated by GPCR include vital responses, such as the maintenance of circulatory homeostasis by augmenting heart pump function and by constricting vascular smooth muscle to maintain blood pressure. In addition, disordered cellular regulation by GPCR has been implicated in a wide variety of diseases, including hypertension, congestive heart failure and cardiac hypertrophy. Thus, the studies detailed here to further understand the molecular mechanisms of receptor activation have broad implications for our knowledge of critical physiological control systems, and may lead to novel therapeutic approaches to treat a variety of diseases.Read moreRead less
Molecular Regulation Of Metabolism And Body Composition By Ski Via Crosstalk With Nuclear Hormone Receptor Signalling.
Funder
National Health and Medical Research Council
Funding Amount
$558,441.00
Summary
Obesity is a common and burdensome health problem in the community which leads to diabetes and heart disease. A number of factors, including hormones play important roles in determing risk of obesity. This study proposes to investigate whether the Ski gene which is a regulatory factor for many hormones affects metabolism in transgenic mouse models of altered Ski function. The proposed studies may identify Ski as a target for therapy for obesity and improvement in sketal muscle metabolism.
Role Of IGF Binding Protein-3 (IGFBP-3) And IGFBP-5 As Modulators Of Nuclear Hormone Signalling
Funder
National Health and Medical Research Council
Funding Amount
$465,750.00
Summary
The insulin-like growth factors are small proteins involved in the growth of most tissues. Their actions are regulated by binding to larger proteins (known as IGFBPs) in the bloodstream and outside the cell. However, some IGFBPs are also found inside cells, where they seem to carry out other functions. We believe that two of these binding proteins, IGFBP-3 and IGFBP-5, change the way cells respond to vitamin A and vitamin D. These two vitamins are important in cell growth and in the way certain ....The insulin-like growth factors are small proteins involved in the growth of most tissues. Their actions are regulated by binding to larger proteins (known as IGFBPs) in the bloodstream and outside the cell. However, some IGFBPs are also found inside cells, where they seem to carry out other functions. We believe that two of these binding proteins, IGFBP-3 and IGFBP-5, change the way cells respond to vitamin A and vitamin D. These two vitamins are important in cell growth and in the way certain cells perform specialised functions. In test-tube experiments, IGFBP-3 and IGFBP-5 interact directly with the receptors that regulate the effects of these hormones. If the same thing happens inside the cell, IGFBP-3 and IGFBP-5 could change the way these receptors respond to signals from outside the cell. We will investigate what effect these IGFBPs have in living cells and in whole animals and how this may relate to human disease. If we are able to understand how IGFBP-3 and IGFBP-5 affect the way cells respond to vitamin A and D, then we may be able to develop new ways to treat certain human diseases.Read moreRead less