Identification And Characterisation Of A Gene Causing Insulin Hypersecretion In A Mouse Model Of Diabetes Susceptibility
Funder
National Health and Medical Research Council
Funding Amount
$430,320.00
Summary
Diabetes is a disorder primarily characterised by the inability to produce and secrete the pancreatic hormone insulin, which regulates plasma sugar levels. This results in increased sugar levels which cause diabetic complications such as retinopathy and nephropathy. The inability to produce and secrete insulin is due to both defects in function as well as a reduction in pancreatic beta cells. Paradoxically it has been shown that some patients who are at risk of develping diabetes actually secret ....Diabetes is a disorder primarily characterised by the inability to produce and secrete the pancreatic hormone insulin, which regulates plasma sugar levels. This results in increased sugar levels which cause diabetic complications such as retinopathy and nephropathy. The inability to produce and secrete insulin is due to both defects in function as well as a reduction in pancreatic beta cells. Paradoxically it has been shown that some patients who are at risk of develping diabetes actually secrete more insulin than normal. Furthermore it has been suggested that this increase in insulin secretion actually may be associated with the decreased production and secretion of insulin characteristic of diabetes. The DBA-2 mouse is a model of reduced insulin production and secretion when exposed to high sugar levels or diabetes. However we have shown that in the normal non-stressed state DBA-2 mice actually secrete more insulin than normal and that this occurs from a very early age, suggesting that this trait is inherited. We have subsequently performed genetic studies and have identified a segment of DNA containing 10 genes associated with increased insulin secretion in DBA-2 mice. The level of one of these genes we have called Hip1 is increased 5-fold in DBA-2 mice, providing a candidate gene for increased insulin secretion in this model of diabetes susceptibility. However, whether Hip1 is also responsible for reduced insulin production and secretion in the DBA-2 mouse is not known. Therefore the overall hypothesis of this project is that the gene Hip1 which is associated with increased insulin secretion is also responsible for reduced insulin production and secretion when DBA-2 mice are exposed to high sugar or obesity. Determining why Hip1 is increased and whether it results in diabetes in DBA-2 mice may provide a reasonable candidate for the development of therapeutic interventions which may prevent the progression of diabetes in some patients.Read moreRead less
Kallikrein Gene Variants In Prostate Cancer: Analysis Of Gene Regulation And Diagnostic/Prognostic Use
Funder
National Health and Medical Research Council
Funding Amount
$486,801.00
Summary
Prostate cancer is the most common male cancer in Australia. However, early detection through screening programs has proven challenging, and about 30% of the 10,000 new cases diagnosed annually already have advanced disease. Hence, there is a fundamental need for increased basic research in prostate cancer etiology (cause) and tumour biology, and a critical requirement for methods that will assist in earlier detection of the disease and predict progression. A family of proteins called kallikrein ....Prostate cancer is the most common male cancer in Australia. However, early detection through screening programs has proven challenging, and about 30% of the 10,000 new cases diagnosed annually already have advanced disease. Hence, there is a fundamental need for increased basic research in prostate cancer etiology (cause) and tumour biology, and a critical requirement for methods that will assist in earlier detection of the disease and predict progression. A family of proteins called kallikreins (including prostate specific antigen, PSA) are often associated with clinical features of prostate cancer. We will characterise genetic variants (polymorphisms) in kallikrein genes that are consistently over-produced in prostate cancer, and determine whether they cause more protein to be produced in cells grown in the laboratory and in tumour tissue, and-or give rise to different expression products or splice variants. We will use bioinformatics (computer programs) to characterise published kallikrein gene sequences and to examine them for genetic variants that might be related to changes in gene expression or to splice variants. We will then use a case-control study, involving 1200 men with prostate cancer and 1200 healthy men, to determine whether these gene variants are associated with an increased risk of prostate cancer or with clinical aspects of the disease. Finally, we will examine the functional significance of the gene variants. This project represents an important and novel combination of molecular biology with the study of clinical disease at the population level, in the relatively new field of molecular epidemiology. It will clarify the role of kallikrein gene variants in prostate cancer risk and progression. The technologies may ultimately prove useful clinically for diagnosis of prostate cancer or for monitoring of treatment and prognosis, and hopefully will assist in clinical decision-making.Read moreRead less
Discovery Early Career Researcher Award - Grant ID: DE120100434
Funder
Australian Research Council
Funding Amount
$375,000.00
Summary
Estrogen-mediated regulation of gene expression via transcriptional and translational control: complementary, synergistic or opposing responses? Hormones dictate cellular behaviour by activating pre-programmed responses. The sex hormone estrogen affects cell fate by regulating the gene expression, but it is unknown to which extent this response occurs via activation of genes or control of already transcribed gene. The project will investigate how the cell integrates the complex estrogen signals.