In Vivo And In Vitro Studies Of The Human -308 TNF Promoter Polymorphism.
Funder
National Health and Medical Research Council
Funding Amount
$232,131.00
Summary
The identification of genetic variation in region of the DNA that controls expression of the inflammatory cytokine Tumour Necrosis Factor (TNF) and its association with a number of autoimmune and inflammatory diseases, has led to speculation that this genetic difference may play a role in predisposing some people to these diseases. We have isolated an activity, TPF1, that may regulate expression through interaction with this DNA control region. During the tenure of this grant we intend to clarif ....The identification of genetic variation in region of the DNA that controls expression of the inflammatory cytokine Tumour Necrosis Factor (TNF) and its association with a number of autoimmune and inflammatory diseases, has led to speculation that this genetic difference may play a role in predisposing some people to these diseases. We have isolated an activity, TPF1, that may regulate expression through interaction with this DNA control region. During the tenure of this grant we intend to clarify some of these questions, we will generate genetically modified mice that have either of the two genetic forms of the human TNF promoter. These mice will be compared in two models of associated disease, murine Lupus and cerebral malaria. We will also characterise the interactions of TPF1 with other components of the TNF control region. An understanding of the role of TPF1 in controlling TNF expression and an appreciation of the cell types that are able to express the phenotype, will allow the development of more subtle, cell specific strategies to modulate the activity of TNF without completely abolishing expression and may lead to better preventative and therapeutic strategies.Read moreRead less
Molecular Mechanisms For The Cell-type Specific Regulation Of The Tissue-type Plasminogen Activator Gene
Funder
National Health and Medical Research Council
Funding Amount
$490,500.00
Summary
Tissue-type plasminogen activator (t-PA) is an important enzyme that is widely known for its ability to remove blood clots. More recently, t-PA has been shown to influence memory development and under pathological conditions can promote neuronal cell death. t-PA is produced by many cells including the endothelial cells that line the blood vessels, fibroblasts, as well as cells within the central nervous system. The t-PA gene is regulated very differently in these cell types and this project will ....Tissue-type plasminogen activator (t-PA) is an important enzyme that is widely known for its ability to remove blood clots. More recently, t-PA has been shown to influence memory development and under pathological conditions can promote neuronal cell death. t-PA is produced by many cells including the endothelial cells that line the blood vessels, fibroblasts, as well as cells within the central nervous system. The t-PA gene is regulated very differently in these cell types and this project will address the mechanisms underlying the cell-type specific regulation of the t-PA gene. Endothelial cells, fibroblasts and neuronal cell cultures will be used to study the regulation of t-PA expression. Information gained will not only add to the understanding of the broader field of gene regulation, but may also provide clues to manipulate the expression of the t-PA gene in different cells.Read moreRead less
Epigenetic Inheritance Through Meiosis At The Agouti Locus In Mice
Funder
National Health and Medical Research Council
Funding Amount
$182,699.00
Summary
The manifestations of many genetic traits do not conform to the rules of Mendelian inheritance. In humans, some alleles give a completely predictable phenotype, while others display a wide range of phenotypes, described as differences in penetrance and expressivity. As the phenotype associated with a particular gene in humans may be modified by the genotype at unlinked modifying loci and by environmental factors, it is difficult to determine to what extent any single factor is responsible for va ....The manifestations of many genetic traits do not conform to the rules of Mendelian inheritance. In humans, some alleles give a completely predictable phenotype, while others display a wide range of phenotypes, described as differences in penetrance and expressivity. As the phenotype associated with a particular gene in humans may be modified by the genotype at unlinked modifying loci and by environmental factors, it is difficult to determine to what extent any single factor is responsible for variability. In mice, however, a number of examples of variable expressivity have been reported in conditions where genetic background and environment have been controlled. For example, the phenotypes of mice with mutations at the agouti locus can vary substantially between genotypically identical littermates. Epigenetic modifications such as DNA methylation are known to be involved. Furthermore, the phenotypes of the offspring are related to the phenotype of the mother and recent experiments carried out in our laboratory suggest that this is the result of inheritance of the epigenetic state of the allele through the female germline. This is the first report of epigenetic inheritance at an endogenous gene in mammals. The experiments described in this project should help to clarify the mechanisms involved in variable expressivity and epigenetic inheritance. Variable expressivity in combination with epigenetic inheritance may be viewed as an alternative method of inheritance of genetic traits which does not involve DNA mutation, but which can be carried from generation to generation in a semipermanent way. Understanding the mechanisms underlying these phenomena is a challenge for contemporary genetics.Read moreRead less