Insulin triggers glucose uptake into fat and muscle tissue, a process that is defective in type 2 diabetes. Insulin does this by triggering a complex cascade of actions once it binds to muscle and fat cells. We will analyse the function of a crucial protein within this cascade. This protein is mutated in humans with severe insulin resistance and our proposed project will dissect how this protein works potentially providing a novel drug target to treat diabetes.
Analysis Of The Role Of Vesicle Docking/Fusion Proteins In Trafficking Of The Glut4 Glucose Transporter In Adipocytes
Funder
National Health and Medical Research Council
Funding Amount
$212,036.00
Summary
The objective of these studies is to understand the molecular mechanisms that are involved in the control of blood glucose levels by the hormone insulin. Elevated blood glucose levels following a meal stimulate the pancreas to release insulin into the circulation. Insulin acts to reduce blood sugar levels by stimulating the uptake of glucose into fat and muscle and suppressing glucose production by the liver. Defects in insulin action in these tissues are the primary cause of Type II diabetes. T ....The objective of these studies is to understand the molecular mechanisms that are involved in the control of blood glucose levels by the hormone insulin. Elevated blood glucose levels following a meal stimulate the pancreas to release insulin into the circulation. Insulin acts to reduce blood sugar levels by stimulating the uptake of glucose into fat and muscle and suppressing glucose production by the liver. Defects in insulin action in these tissues are the primary cause of Type II diabetes. The debilitating effects of Type II diabetes, the dramatic increase its incidence, and the expense of treating the symptoms of diabetic complications have lead to the realization that the disease represents a major health problem requiring substantial research and development efforts. The project will focus on insulin regulation of glucose uptake in fat cells. Insulin promotes glucose uptake into fat by activating an intracellular signaling pathway that triggers the translocation of a unique glucose transporter protein (Glut4) from storage sites inside the cell to the cell surface. Glut4 translocation is mediated by small membrane vesicles that function to sequester the glucose transporter inside cells in the absence of insulin, and to shuttle Glut4 to the cell surface in response to the hormone. Despite the central importance of this event to the maintenance of normal blood glucose levels, it is poorly understood. The studies will be directed towards investigating the cellular machinery involved in the latter stages of insulin-stimulated glucose uptake- the vesicle-mediated delivery of Glut4 to the cell surface. The objective of these studies is to better understand the molecular basis for Glut4 translocation, and regulation by the insulin signaling cascade. Accomplishment of this goal may suggest potential drug intervention strategies aimed at enhancing insulin-stimulated Glut4 translocation and promoting improved control of blood glucose levels in Type II diabetes.Read moreRead less
Molecular Dissection Of The Munc18c:Syntaxin4 Complex Required For Insulin-regulated Exocytosis In Adipocytes
Funder
National Health and Medical Research Council
Funding Amount
$601,008.00
Summary
When blood glucose levels are high, insulin signals to fat and muscle cells to remove glucose from the blood. The uptake of glucose relies on membrane fusion events that deliver a specific glucose transporter protein to the cell surface in response to insulin signals. This process is affected in Type II diabetes. Our research will characterise the regulation of these membrane fusion events and will be important for understanding how insulin signals are communicated in health and disease.
Many bacterial pathogens invade host cells to replicate and avoid detection by the host. These pathogens interact with the host and by manipulating it to its benefit they establish an environment to survive in. A detailed understanding of the targeted hosts pathways and which are essential for pathogen survival is knowledge that will allow future development of therapeutic intervention strategies.
The Role Of Dysferlin In Muscular Dystrophy And Skeletal Muscle Membrane Repair.
Funder
National Health and Medical Research Council
Funding Amount
$316,667.00
Summary
Patients who lack the protein dysferlin have muscular dystrophy. These patients are unable to repair their muscle membranes, which get damaged during normal activities. A defect in membrane repair is a new pathway implicated in the muscular dystrophies, and it is likely that other patients will also have defective muscle membrane repair. We will find out how dysferlin mediates its role in membrane repair, and identify other dysferlin-interacting proteins, as these may also underlie disease.