Cytokine Secretion: A Model For Protein Trafficking.
Funder
National Health and Medical Research Council
Funding Amount
$204,111.00
Summary
TNF-a is an inflammatory cytokine with important roles in host defense, tumour regulation and energy homeostatis, however the oversecretion of TNF-a is also a major cause of septic shock, rheumatoid arthritis, Chron?s disease and the cachexia of cancer. TNF-a synthesis and its release from the surface of cells are relatively well understood. However little is known about its trafficking through the secretory pathway of cells. Understanding this process has the potential to provide new ways of co ....TNF-a is an inflammatory cytokine with important roles in host defense, tumour regulation and energy homeostatis, however the oversecretion of TNF-a is also a major cause of septic shock, rheumatoid arthritis, Chron?s disease and the cachexia of cancer. TNF-a synthesis and its release from the surface of cells are relatively well understood. However little is known about its trafficking through the secretory pathway of cells. Understanding this process has the potential to provide new ways of controlling the secretion of TNF-a. In previous work we have characterized transport vesicles and cytoskeletal proteins involved in secretory pathways of epithelial cells. We now propose to focus on the characterization of transport vesicles, and the roles of actin and myosins involved in TNF-a secretion in macrophages. These studies will rely on introducing new technology to this line of research. Fluorescent tagged constructs of TNF-a will be expressed and viewed in living cells to analyse the secretory pathway and measure the transport of TNF-a from its site of accumulation in the Golgi complex to the cell surface. This work aims to identify membrane-bound vesicles and vesicle-associated proteins that target TNF-a for secretion. We will begin to investigate the role of actin and myosins, using drugs and microinjected peptides to block their function. Overall these studies will provide important cell biological information about protein trafficking in cells. Cytokine secretion is important in immunity and cancer, information important to both fields will be gained from these studies.Read moreRead less
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
Identification Of The Plasmodium Falciparum Translocon That Exports Parasite Proteins Into Their Erythocytic Hosts.
Funder
National Health and Medical Research Council
Funding Amount
$409,027.00
Summary
Up to 10% of the world's population will suffer from malaria in any given year and for over a million this disease will be fatal. This devastating disease is caused by the parasite Plasmodium falciparum that infects and destroys our red blood cells. Infected red cells are greatly modified by the parasites so they can feed and avoid elimination by the human immune system. We wish to investigate the red blood cell modification process and assess it as a potential target for anti-malarial drugs.