Investigating The Physiological And Biochemical Role Of SOCS5 In The Immune System
Funder
National Health and Medical Research Council
Funding Amount
$405,940.00
Summary
Asthma affects millions of people worldwide and is a complex inflammatory disease of the lung. Asthma manifests as recurrent episodes of wheezing, breathlessness, chest tightening, and coughing. Three key proteins called; interleukin 4 (IL-4), interleukin 13 (IL-13) and interleukin 5 (IL-5) are produced by a subset of white blood cells (T helper cells; Th2) and are thought to be responsible for the asthma response. Normally these proteins act to coordinate the body s immune defence against paras ....Asthma affects millions of people worldwide and is a complex inflammatory disease of the lung. Asthma manifests as recurrent episodes of wheezing, breathlessness, chest tightening, and coughing. Three key proteins called; interleukin 4 (IL-4), interleukin 13 (IL-13) and interleukin 5 (IL-5) are produced by a subset of white blood cells (T helper cells; Th2) and are thought to be responsible for the asthma response. Normally these proteins act to coordinate the body s immune defence against parasite infection. In other words, asthma is thought to arise through inappropriate IL-4 and IL-13 activity in the absence of a parasite infection. Extra IL-13 is commonly found in the lungs of asthmatics and is thought to help trigger asthma attacks. IL-13 is a validated target for drugs that could be used in the treatment of asthma. The SOCS genes were discovered in our laboratory and by genetically deleting the genes in mice we have demonstrated a critical role for SOCS1, SOCS2 and SOCS3 in regulating the immune response and the action of growth hormone. My hypothesis is that SOCS5 is an important physiologic regulator of the asthma response. This proposal will investigate the basic biochemical processes underlying the regulation of IL-4 and IL-13 action and the relationship to development of asthma and immune disease. I plan to induce asthma attacks in mice that lack the genes for SOCS4 and SOCS5. If the severity of the attacks is greater in the absence of these proteins this will indicate that SOCS4 and-or SOCS5 are important negative regulators of IL-4 and IL-13. This has the potential to open up a completely new strategy for the development of drugs that could be used in the prevention and treatment of asthma.Read moreRead less
Characterization Of Novel Regulators Of Erythropoiesis
Funder
National Health and Medical Research Council
Funding Amount
$437,545.00
Summary
Mature red and white blood cells develop from hemopoietic stem cells in the adult bone marrow. The production of red blood cells is primarily controlled by the hormone erythropoietin (epo). The availability of this hormone in a recombinant form has aided in the treatment of numerous forms of anaemia resulting from kidney failure, malignancies, and AIDS. Previously we had identified that the protein Lyn must be present inside primitive red blood cells for epo to stimulate them to become mature fu ....Mature red and white blood cells develop from hemopoietic stem cells in the adult bone marrow. The production of red blood cells is primarily controlled by the hormone erythropoietin (epo). The availability of this hormone in a recombinant form has aided in the treatment of numerous forms of anaemia resulting from kidney failure, malignancies, and AIDS. Previously we had identified that the protein Lyn must be present inside primitive red blood cells for epo to stimulate them to become mature functional cells. We have identified six molecules which interact with Lyn in red blood cells. We have shown that amolecule called HS1 is important for epo function in individual red blood cells and now we plan to investigate its functions in whole animals, including mice that lack the HS1 gene. We have also shown that a molecule called Trip1 is important for red blood cell development. Interestingly, this molecule also interacts with the thyroid hormone receptor and can influence the effects of epo and thyroid hormone on red blood cell development. The interplay between these two hormones will be looked at in more detail both at the cell and whole animal levels in normal mice and those lacking the thyroid hormone receptor gene. The third Lyn binding molecule we isolated is a novel gene-we have named it ankyrin repeat protein in line with the molecules it is related to. This gene is expressed in red blood cells and we aim to investigate what role it plays in the development of these cells. The fourth gene is also novel and is closely related to another called AFAP-110, which can exert effects on the structure of a cell. Its role in red blood cell structure will also be investigated. Finally, the last two molecule we have identified are both novel and are unrelated to any other known proteins. As above, the effects of these two molecules on red blood cell development will be investigated.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.
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
The Structural Basis Of Cytokine Signalling Inhibition
Funder
National Health and Medical Research Council
Funding Amount
$239,473.00
Summary
Cell-cell communcation is vital for the correct functioning of the body. Cells need to be told the correct time to divide, to produce certain enzymes or chemicals, to migrate and also when to apoptose, or die. Cells receive these signals through the binding of small soluble proteins called cytokines. Cytokines bind to specialized receptors on the surface of the cell and initiate an intracellular signaling cascade that passes the correct message to the nucleus. It is important that cells react to ....Cell-cell communcation is vital for the correct functioning of the body. Cells need to be told the correct time to divide, to produce certain enzymes or chemicals, to migrate and also when to apoptose, or die. Cells receive these signals through the binding of small soluble proteins called cytokines. Cytokines bind to specialized receptors on the surface of the cell and initiate an intracellular signaling cascade that passes the correct message to the nucleus. It is important that cells react to these protein messengers however it is just as vital that they don't overreact. Many human diseases, especially inflammatory diseases such as rheumatoid arthritis and type II diabetes, are due to aberrant cytokine signaling. To ensure this doesn't occur, cells have evolved a mechanism to quickly switch off the signaling cascade after it has started. This mechanism involves an entire family of proteins, the Suppressors of Cytokine Signalling (SOCS) family. These proteins can act via two distinct mechanisms. The first is to directly block the JAK-STAT proteins, proteins that initiate the intracellular part of the signaling cascade. The second mechanism has been less well studied, it involves the SOCS proteins upregulating the degradation of signaling intermediates. The SOCS proteins can do this through the action of a 40 residue domain called the SOCS box. The SOCS box directs proteins bound to other domains of the SOCS proteins to be degraded by interacting with a complex called an E3 ubiquitin ligase. This project involves determining the three-dimensional atomic structure of the SOCS-E3 ligase interaction and investigating biophysical aspects of the interaction. This information will lead to a fuller understanding of the mechanism of signaling inhibition and will provide information crucial to the design of SOCS inhibitors. Such inhibitors would be therapeutically important in the treatment of a number of human diseases such as cancer, arthritis and type II diabetes.Read moreRead less
Recent evidence suggests that the Siah proteins are involved in sensing low oxygen levels in cells, and subsequently activating processes to help the cell survive under these conditions. Low oxygen conditions occur in cancer and sites of inflammation, suggesting that inhibiting Siah may improve patient outcomes in diseases such as cancer and arthritis. We aim to perform a high throughput screen for drugs that inhibit Siah protein function and to test these in cancer cells.
Structural Characterisation Of SNARE Protein Complexes Involved In Insulin-regulated Glucose Transport
Funder
National Health and Medical Research Council
Funding Amount
$320,803.00
Summary
Insulin-regulated glucose transportation is defective in type 2 diabetes, a disease that is a major health problem worldwide and in some cases can lead to death. The aim of this work is to investigate the molecular structure and function of proteins critical to the transportation and delivery of glucose to muscle and fat cells, which will lead to the validation of new therapeutic targets and the development of new treatments for diabetes.
Role Of FHA Domains As Protein-protein Interaction Modules In Cell Signalling
Funder
National Health and Medical Research Council
Funding Amount
$191,973.00
Summary
The proper processing of information in cells involves the association of different proteins to signalling complexes. We will decipher the role the so-called FHA module plays in the formation of protein complexes. FHA modules are present in several proteins that are important for the repair of damaged DNA and the stability of chromosomes. Understanding the structure and function of this module will be relevant for various forms of cancer where DNA is damaged.