Molecular Determinants Of Subcellular Localisation And Function Of The Transmembrane 4 Superfamily Protein, PETA-3
Funder
National Health and Medical Research Council
Funding Amount
$322,911.00
Summary
Several years ago we identified the cell membrane protein PETA-3-CD151 based on its ability to cause activation of blood platelets, suggesting a role in thrombosis. More recently we found that the protein is present in a variety of tissues, although its distribution in those tissues is often restricted. It is abundant in a variety of cancer cells, and is present on tissue mast cells that mediate allergic reactions. PETA-3-CD151 forms complexes with molecules (integrins) that are associated with ....Several years ago we identified the cell membrane protein PETA-3-CD151 based on its ability to cause activation of blood platelets, suggesting a role in thrombosis. More recently we found that the protein is present in a variety of tissues, although its distribution in those tissues is often restricted. It is abundant in a variety of cancer cells, and is present on tissue mast cells that mediate allergic reactions. PETA-3-CD151 forms complexes with molecules (integrins) that are associated with cell adhesion and migration, and antibodies to this protein inhibit cell movement. Thus PETA-3-CD151 appears to be involved in cellular interactions that are critical for normal tissue development and function, and may be involved in several disease processes including cancer invasion and metastasis. The molecular basis of PETA-3-CD151 function is not understood and is the focus of this application.Read moreRead less
Regulation Of Hedgehog Signalling Through Intracellular Trafficking Events
Funder
National Health and Medical Research Council
Funding Amount
$220,500.00
Summary
The hedgehog signalling cascade plays a role in forming almost every organ of the body during development of an embryo. Perturbation of the function of key members of this pathway during embryonic development often results in death in utero or severe childhood abnormalities. In addition, disruption to this pathway also results in a range of cancers, most notably the extremely common skin cancer basal cell carcinoma. In this proposal we aim to investigate in detail the regulatory mechanisms which ....The hedgehog signalling cascade plays a role in forming almost every organ of the body during development of an embryo. Perturbation of the function of key members of this pathway during embryonic development often results in death in utero or severe childhood abnormalities. In addition, disruption to this pathway also results in a range of cancers, most notably the extremely common skin cancer basal cell carcinoma. In this proposal we aim to investigate in detail the regulatory mechanisms which operate to ensure that this complex pathway of interacting molecules functions correctly during embryonic development. By understanding how this regulation occurs we will gain valuable insight into how disruption of this pathway results in such a range of disease, as well as into how agents which modulate this pathway may potentially act in a therapeutic setting.Read moreRead less
The mechanisms and roles of receptor clustering in cell activation and wound healing by growth factors. Growth factors regulate cell proliferation, migration and differentation by interaction with receptors. Such receptors are usually localized at the cell surface, and require intracellular transduction systems to transmit the signal to the cell interior. We have recently shown the hormone-induced clustering of heterologous hormone receptors in cells, and that this occurs with the co-clustering ....The mechanisms and roles of receptor clustering in cell activation and wound healing by growth factors. Growth factors regulate cell proliferation, migration and differentation by interaction with receptors. Such receptors are usually localized at the cell surface, and require intracellular transduction systems to transmit the signal to the cell interior. We have recently shown the hormone-induced clustering of heterologous hormone receptors in cells, and that this occurs with the co-clustering of downstream signalling molecules at sites of engagement with the extracellular matrix. In addition, we have found that cells presented with an extracellular matrix respond better to subsequent growth factor stimulation. The project aims to determine the cellular mechanisms underlying receptor clustering and the basis of the receptor-extracellular matrix interaction. This will enhance our understanding of growth factor function in a number of conditions, including wound healing. We will extend our in vitro results to the animal model to define parameters for enhanced wound repair.Read moreRead less
Characterisation Of A New Family Of Proteins Involved In Cell Signalling, RNA Metabolism And Cancer
Funder
National Health and Medical Research Council
Funding Amount
$200,880.00
Summary
We have discovered a novel RNA-binding protein (G3BP-2) that is involved in responding to external signals, such as growth factors, at the level of gene expression. Other RNA-binding proteins belonging to the same broad group of proteins are responsible for a host of disease states in mammals including mental retardation, myotonic dystrophy, Huntington?s disease and cancers. Considering the wealth of knowledge accumulated that implicates these proteins to human dysfunction surprisingly few of th ....We have discovered a novel RNA-binding protein (G3BP-2) that is involved in responding to external signals, such as growth factors, at the level of gene expression. Other RNA-binding proteins belonging to the same broad group of proteins are responsible for a host of disease states in mammals including mental retardation, myotonic dystrophy, Huntington?s disease and cancers. Considering the wealth of knowledge accumulated that implicates these proteins to human dysfunction surprisingly few of these RNA-binding proteins have been identified. We have shown that the novel protein discovered in our laboratory is perturbed in cancer and we are interested in characterising its putative role in cancer. The results established in our laboratory so far would indicate that generally, G3BP-2 is expressed in normal tissue and it expression changes in some cancers studied so far. Considering that G3BP-2 lies in a pathway known to be involved in cancer progression it is important to understand what effects the inappropriate expression of G3BP-2 may have on cancer progression and survival. This project is designed to characterise what signals the cell uses to control these proteins and in turn which genes these may effect. In this way we may be able to determine how external signals may effect tumour progression and on what genes this influence is expressed. It would be hoped that this project would increase our understanding of cancer and potentially lead to new diagnostic reagents and therapies in the treatment of cancer.Read moreRead less
Regulation Of The Tumour Suppressors APC And BRCA1 By Nuclear Export
Funder
National Health and Medical Research Council
Funding Amount
$530,874.00
Summary
Cancer cells lack the ability to control their own growth, and thus continously divide in their local environment, leading to tumour formation. Tumour suppressor proteins, like APC and BRCA1, normally function as regulators to help cells respond to outside signals and to stop growing when necessary. The inactivation and altered cellular localisation of tumour suppressor proteins can contribute to cancer development. We have found that the APC and BRCA1 proteins, whose inactivation leads to devel ....Cancer cells lack the ability to control their own growth, and thus continously divide in their local environment, leading to tumour formation. Tumour suppressor proteins, like APC and BRCA1, normally function as regulators to help cells respond to outside signals and to stop growing when necessary. The inactivation and altered cellular localisation of tumour suppressor proteins can contribute to cancer development. We have found that the APC and BRCA1 proteins, whose inactivation leads to development of colon cancer and breast cancer, respectively, contain signals that dictate their movement within the cell. Our novel preliminary findings reveal that APC and BRCA1 are able to move in and out of the cell nucleus. We aim to define how this occurs, and examine how the regulation of their cellular location affects the normal function of these cancer-suppressing proteins. Finally, abnormalities in the nuclear passage of APC or BRCA1 might explain their altered cellular location in cancer cells.Read moreRead less
Regulated Shuttling Of Beta-catenin And IQGAP1 Between Nucleus And Plasma Membrane In Migrating Cells
Funder
National Health and Medical Research Council
Funding Amount
$511,703.00
Summary
Inherited gene mutations that cause colon cancer kill 4,700 Australians every year. About 1 in 21 Australians develop colorectal cancer by age 75. Activation of the beta-catenin protein is a critical switch in the path to colon cancer. We discovered that beta-catenin, and another protein it interacts with called IQGAP1, move between different cellular compartments. We plan to study this process in more detail, as it relates to how beta-catenin works and to understanding its role in cancer.
Molecular, genetic and cellular analysis of melanisation in human pigmentation. This investigation examines variations in the genes that determine human skin pigmentation and are likely to be associated with skin cancer risk. Our research program will form the basis of future diagnostics based on major genes that determine a persons skin type. Current skin cancer prevention strategies rely predominantly on broad spectrum campaigns that are aimed at increasing the general community awareness of ....Molecular, genetic and cellular analysis of melanisation in human pigmentation. This investigation examines variations in the genes that determine human skin pigmentation and are likely to be associated with skin cancer risk. Our research program will form the basis of future diagnostics based on major genes that determine a persons skin type. Current skin cancer prevention strategies rely predominantly on broad spectrum campaigns that are aimed at increasing the general community awareness of the damaging effects of ultraviolet (UV) radiation. A better understanding of the genetic basis of UV-sensitive skin types will greatly enhance the targeting of such skin cancer-prevention campaigns, provide an understanding of changes that occur in skin pathology, and the mechanisms of sun induced tanning.Read moreRead less
Targeting Of The APC Tumour Suppressor To Mitochondria: Implications For APC Regulation And Cellular Function
Funder
National Health and Medical Research Council
Funding Amount
$390,116.00
Summary
Inherited mutations in the APC gene cause colon cancer, and kills 4,700 Australians every year. About 1 in 21 Australians develop colorectal cancer by the age of 75. APC mutations change cells in different ways, triggering the cancer process. We have discovered a new pathway, involving altered movement of APC to mitochondria in tumour cells. This study will investigate how this cancerous change may help our understanding of colon cancer progression.
The regulated movement of membrane receptors and ligands between the cell surface and intracellular compartments is vital to many cellular operations, including communication between cells and their environment. However, the molecular details of these sorting events remain poorly defined. Determination of the mechanisms that control the cellular distribution of receptors is critical for understanding normal cellular processes and in pathological processes like tumorigenesis.