Regulation Of SRC-Family And Focal Adhesion Kinase Function
Funder
National Health and Medical Research Council
Funding Amount
$381,338.00
Summary
Cells in our bodies stick to one another and to the cementing material called extracellular matrix surrounding them. An ezyme called focal adhesion kinase (FAK) is a major regulator of cell stickiness. It can catalyze the covalent attachment of a chemical group called phosphate to specific cellular protein. This proposal aims at studying how FAK is regulated by insulin stimulation and how FAK is regulated by a tumour suppressor called PTEN. Results of the study will shed light on how abberration ....Cells in our bodies stick to one another and to the cementing material called extracellular matrix surrounding them. An ezyme called focal adhesion kinase (FAK) is a major regulator of cell stickiness. It can catalyze the covalent attachment of a chemical group called phosphate to specific cellular protein. This proposal aims at studying how FAK is regulated by insulin stimulation and how FAK is regulated by a tumour suppressor called PTEN. Results of the study will shed light on how abberrations in the regulation and PTEN contribute to the development of development defects, heart attack, and the spreading of cancer cells.Read moreRead less
Regulation Of The Tumour Suppressor PTEN By Phosphorylation And Oligomerization
Funder
National Health and Medical Research Council
Funding Amount
$241,650.00
Summary
The tumour suppressor PTEN is an enzyme involved in controlling cell growth, cell death, and cell migration. PTEN was identified as a tumour suppressor because many tumour cells were found to carry mutations in the PTEN gene that cause the loss of PTEN protein or the loss of PTEN enzyme activity. Hereditary mutations of the PTEN gene are the causes of a rare genetic disease called Cowden's disease. Cowden's disease patients are predisposed to developing skin, thyroid, and breast cancers. In labo ....The tumour suppressor PTEN is an enzyme involved in controlling cell growth, cell death, and cell migration. PTEN was identified as a tumour suppressor because many tumour cells were found to carry mutations in the PTEN gene that cause the loss of PTEN protein or the loss of PTEN enzyme activity. Hereditary mutations of the PTEN gene are the causes of a rare genetic disease called Cowden's disease. Cowden's disease patients are predisposed to developing skin, thyroid, and breast cancers. In laboratory conditions, increasing the abundance of PTEN in tumour cells such as brain and prostate tumour cells can suppress their growth, hence its role as a tumour suppressor. In addition to its role as a tumour suppressor, PTEN controls cancer cell spreading. Although much is known about the involvement of PTEN in cancer formation and the spreading of cancer cells, how PTEN suppresses tumour cell growth and spreading is not fully understood. The enzyme activity of PTEN enhances the removal of a chemical group called phosphate group from proteins and the fat-soluble compounds called phospholipids in the cell membrane. The ability of PTEN to suppress cell growth and spreading is due to its enzyme activity. However, exactly how the enzyme activity of PTEN is regulated is not well understood. In order for PTEN to efficiently enhance the removal of phosphate group from specific cellular proteins and phospholipids, PTEN needs to be located in close vicinity to these proteins and phospholipids. However, exactly how PTEN moves to the locations where these proteins and phospholipids are present remains elusive. This proposal aims at studying the regulation of PTEN enzyme activity and movement inside the cells. Results of the proposed studies will shed new light on how PTEN gene mutations contribute to cancer formation and the spreading of cancer cells and may facilitate the search for the cure of cancers.Read moreRead less
Alzheimer's Disease And Related Disorders: Mechanism Of Tau Pathology In Established And Novel Transgenic Animal Models
Funder
National Health and Medical Research Council
Funding Amount
$423,017.00
Summary
Alzheimer's disease (AD) is a devastating neurodegenerative disease for which no cure is available. It affects more than 15 million people worldwide. There are estimates that by 2040, approximately 500'000 Australians will suffer from AD, with associated health costs of about 3% of the GDP. AD is characterized by two major brain lesions, beta-amyloid plaques and neurofibrillary tangles (NFTs). The latter contain a protein called tau which is in a fibrillar and highly phosphorylated state. We wer ....Alzheimer's disease (AD) is a devastating neurodegenerative disease for which no cure is available. It affects more than 15 million people worldwide. There are estimates that by 2040, approximately 500'000 Australians will suffer from AD, with associated health costs of about 3% of the GDP. AD is characterized by two major brain lesions, beta-amyloid plaques and neurofibrillary tangles (NFTs). The latter contain a protein called tau which is in a fibrillar and highly phosphorylated state. We were the first to establish a transgenic animal model of pre-tangles and, together with Dr. Hutton's laboratory, of NFT formation. We could further show that injections of beta-amyloid into brains of our tau mutant mice enhanced the NFT pathology in these mice. By Functional Genomics we identied genes and proteins, which are induced by tau expression. The specific aim of this proposal is to determine whether oxidative stress enhances the tau pathology in our tau mutant mice and whether distinct brain areas are particularly susceptible to this kind of stress. The reason for addressing this question is twofold: On the one hand, we have found in our mice that reactive oxygen species are increased, secondly it is known that some brain areas in the AD brain are degenerating, whereas others are not. A second aim is to develop novel tau transgenic models where individual interactions of tau with cellular proteins are disturbed. Finally, we want to determine whether the two kinases BMX and FAK and the phosphatase PPV regulate tau phosphorylation in vivo. Together, we hope that our efforts lead to a better understanding of the pathogenic mechanisms in AD and related disorders. As pathocascades are likely to be shared between a range of diseases, these findings may also contribute to other fields of research, such as Parkinson's disease. Ultimately, these efforts will assist in the development of a safe treatment of AD.Read moreRead less
The Role Of Protein Tyrosine Phosphatases Regulating Eph RTK-signalling And Modulating Invasive Tumour Cell Properties.
Funder
National Health and Medical Research Council
Funding Amount
$303,828.00
Summary
The Ephs and interacting ephrins are proteins on the cell surface, which enable orientation of cells that move within the body tissues and organs, but also in tumours. Eph proteins have tyrosine kinase enzyme activity that becomes active after binding ephrins on neighbouring cells. Once active, they instruct these cells to change their shape and their adhesion to the substratum or between each other, and to become more motile. In adult organisms Ephs and ephrins are low in most cells, but they r ....The Ephs and interacting ephrins are proteins on the cell surface, which enable orientation of cells that move within the body tissues and organs, but also in tumours. Eph proteins have tyrosine kinase enzyme activity that becomes active after binding ephrins on neighbouring cells. Once active, they instruct these cells to change their shape and their adhesion to the substratum or between each other, and to become more motile. In adult organisms Ephs and ephrins are low in most cells, but they re-appear in many tumors. For example, when normal cells in the skin (melanocytes) become tumor cells, they often will have Ephs and ephrins on their surface. It is believed that these proteins will now affect if these melanoma cells will migrate and to which locations within the body. In our studies we will examine what controls the activity of Eph proteins. In particular, a class of enzymes called tyrosine phosphatases are known to regulate the function of tyrosine kinase receptors, however it is not clear which particular phosphatase regulates EphA3, the focus of our studies. We will find out, which set of phosphatases regulates EphA3 function and whether exposure to oxidative conditions, such as UV radiation, also activates Ephs and instructs tumour cells to become more motile and to invade other areas of the body. The understanding of this mechanism will help to understand the cause of cancers such as melanoma and might offer possibilities to optimise new strategies for its treatment.Read moreRead less