Defining The Role And Contribution Of Cdc37 To Signal Transduction And Tumourigenesis By Src-family Kinases
Funder
National Health and Medical Research Council
Funding Amount
$411,430.00
Summary
Cells respond to extracellular stimuli, such as growth factors and hormones, by activating intracellular networks of signaling molecules. It is the activation of these signaling networks that is ultimately responsible for mediating the biological responses of cells to extracellular stimuli (e.g. insulin stimulating glucose metabolism by cells). Members of the Src-family of tyrosine kinases are paramount among signaling molecules, as they are able to directly initiate the activation of a cascade ....Cells respond to extracellular stimuli, such as growth factors and hormones, by activating intracellular networks of signaling molecules. It is the activation of these signaling networks that is ultimately responsible for mediating the biological responses of cells to extracellular stimuli (e.g. insulin stimulating glucose metabolism by cells). Members of the Src-family of tyrosine kinases are paramount among signaling molecules, as they are able to directly initiate the activation of a cascade of signaling networks that regulate the activity of the cell. Significantly though, the inappropriate activation of Src-family kinases has been implicated in the development of cancer, particularly breast and colon cancer, in humans. To fulfill their signaling functions however, Src-family kinases must first be folded into an active conformation upon their synthesis in the cell then be maintained in this conformation. Although previous studies, including our own, have implicated a class of proteins called molecular chaperones in this process, little is known about how the folding of Src-family kinases by these proteins is achieved and regulated. The overall aim of this study is to determine how the folding of Hck, one member of the Src-family of tyrosine kinases, into a conformation that enables it to participate in signaling networks is achieved and regulated. It is expected that the results from this study will provide significant new insight into how this process might influence the ability of cells to respond to extracellular stimuli and potentially contribute to the conversion of a normal cell into one with tumourigenic properties. Findings from this project may be particularly important in the context of human cancer. A better knowledge of how the signaling activity of Src-family kinases is regulated by molecular chaperones might provide a new avenue of investigation for the identification of novel chemotherapeutic agents.Read moreRead less
Escape From BRAF-induced Human Melanocyte Senescence In The Genesis Of Melanoma
Funder
National Health and Medical Research Council
Funding Amount
$601,776.00
Summary
Melanoma is the most lethal form of skin cancer and activation of the MAPK growth pathway is a crucial step in the initiation of this cancer, but alone is insufficient, as most melanocytes with active MAPK exist in a growth arrested state. The mechanisms responsible for arresting melanocytes in the presence of active MAPK will be investigated. This project will discover why some melanocytes develop into melanomas whereas most do not.
Analysis Of Intracellular Signalling And Biological Activities Of The GM-CSF Receptor Family Using Constitutive Mutants
Funder
National Health and Medical Research Council
Funding Amount
$505,699.00
Summary
The cytokines GM-CSF, IL-3 and IL-5 stimulate the growth and actions of a wide range of blood cells. Each binds to a receptor on the cell surface which then triggers the generation of a number of signals inside the cell; it is these signals that are responsible for the cytokine?s actions. We have previously generated a panel of constitutive mutant forms of the beta subunit which is shared by the GM-CSF, IL-3 and IL-5 receptors. These constitutive mutants trigger signals even in the absence of th ....The cytokines GM-CSF, IL-3 and IL-5 stimulate the growth and actions of a wide range of blood cells. Each binds to a receptor on the cell surface which then triggers the generation of a number of signals inside the cell; it is these signals that are responsible for the cytokine?s actions. We have previously generated a panel of constitutive mutant forms of the beta subunit which is shared by the GM-CSF, IL-3 and IL-5 receptors. These constitutive mutants trigger signals even in the absence of the cytokine; importantly, the different mutants appear to trigger only a subset of the signals generated by the normal receptor. The aim of this project is to use our panel of constitutive beta subunit mutants to determine how the GM-CSF, IL-3 and IL-5 receptors generate signals inside the cell and how these signals lead to the various biological actions of the receptors on blood cell growth and maturation. Findings from this research will be relevant to the understanding and treatment of diseases which involve abnormal growth or function of blood cells such as leukaemia and inflammatory diseases.Read moreRead less
The Regulation Of 14-3-3 Protein Function By Post-translational Modification
Funder
National Health and Medical Research Council
Funding Amount
$212,036.00
Summary
The cells of our body have control mechanisms that prevent them from growing abnormally. However, when cells become cancerous they escape the normal checks and controls and are able to survive, divide and grow uncontrollably. In the last decade the molecular basis of several of the control mechanisms involved in preventing cancerous growth have been uncovered. However, our understanding is far from complete and recent research reports suggest that we have thus far overlooked a whole level of reg ....The cells of our body have control mechanisms that prevent them from growing abnormally. However, when cells become cancerous they escape the normal checks and controls and are able to survive, divide and grow uncontrollably. In the last decade the molecular basis of several of the control mechanisms involved in preventing cancerous growth have been uncovered. However, our understanding is far from complete and recent research reports suggest that we have thus far overlooked a whole level of regulation of cell growth control. Signals that instruct a normal cell to divide are propogated by pathways of interacting molecules within the cell. These pathways are regulated by switch mechanisms that either modify the interacting molecules, thereby inactivating their activity or by controlling when and where the molecules are allowed to interact. This spatial and temporal control mechanism is mediated by a family of specialised molecules, called 14-3-3 proteins. Recent research indicates that the function of these 14-3-3 proteins is also tightly controlled, although as yet we don't understand how. This research proposal attempts to discover the molecular mechanism of regulation of 14-3-3 function. An understanding of this process may provide new molecular targets for the development of therapeutics against cancer.Read moreRead less
Ras Signalling And Cholesterol Efflux From Late Endosomes
Funder
National Health and Medical Research Council
Funding Amount
$276,598.00
Summary
Accumulation of cholesterol is a hallmark of early atherosclerotic lesions, known as foam cell formation. Hence the stimulation of cholesterol removal (efflux) from macrophages has great therapeutic potential. High Density Lipoproteins (HDL) and apolipoprotein A-I (apoA-I) stimulate efflux via activation of HDL-apoA-I receptors and poorly understood signalling pathways. This application is investigating the role of the Ras-MAPK signalling pathway in promoting efflux from late endosomes.