Regulation Of Tissue-type Plasminogen Activator Gene Expression In Endothelial Cells And In Transgenic Mice
Funder
National Health and Medical Research Council
Funding Amount
$244,009.00
Summary
Tissue-type plasminogen activator (t-PA) is an enzyme which plays an important role in the removal of blood clots from the circulation. One of the major sites of production of t-PA are endothelial cells which line the blood vessel wall. The rate of t-PA production is greatly influenced by factors released from other cells. One of these factors is tumour necrosis factor (TNF). The t-PA gene is switched off in endothelial cells exposed to TNF. One of the aims of this project is to understand how t ....Tissue-type plasminogen activator (t-PA) is an enzyme which plays an important role in the removal of blood clots from the circulation. One of the major sites of production of t-PA are endothelial cells which line the blood vessel wall. The rate of t-PA production is greatly influenced by factors released from other cells. One of these factors is tumour necrosis factor (TNF). The t-PA gene is switched off in endothelial cells exposed to TNF. One of the aims of this project is to understand how the t-PA gene is suppressed by TNF in human endothelial cells and in transgenic mice. The transgenic mice we have available express the regulatory region of the t-PA gene (called the gene promoter) connected to a reporter gene called LacZ. We will use these animals to visualise the expression pattern of LacZ expression under normal conditions and in mice treated with TNF. The results of these experiments will provide new information as to how the t-PA gene is controlled in cells and in the body.Read moreRead less
The Role Of Ikaros In Establishing Regulatory Networks For Lymphocyte Development
Funder
National Health and Medical Research Council
Funding Amount
$345,809.00
Summary
Ikaros is a protein that regulates gene expression during development of lymphocytes from blood stem cells. Ikaros has a profound importance in normal and malignant lymphocyte development, but we still do not know how it controls these processes. The aim of my study is to identify genes regulated by Ikaros and the molecular mechanisms of their regulation. This study will contribute to understanding of the regulatory network controlling the development and function of lymphocytes.
Gene Transcription In Activated T Cells: A Model Of Chromatin Remodeling.
Funder
National Health and Medical Research Council
Funding Amount
$477,500.00
Summary
Cells of the immune system respond to invasion of the body by infectious or other damaging agents by switching on the production of a large array of proteins that are critical for an orchestrated immune response. Some of these proteins, referred to as cytokines, are secreted by the cells and act as intercellular messengers to affect the function of other cells need for an immune response. Switching on the production of these cytokines requires the genes that produce them to interpret the complex ....Cells of the immune system respond to invasion of the body by infectious or other damaging agents by switching on the production of a large array of proteins that are critical for an orchestrated immune response. Some of these proteins, referred to as cytokines, are secreted by the cells and act as intercellular messengers to affect the function of other cells need for an immune response. Switching on the production of these cytokines requires the genes that produce them to interpret the complex signaling pattern to which the cell has been exposed. These complex signaling patterns are interpreted in the nucleus by molecular switches that lie beside the genes in the DNA. The incorrect production of these proteins is involved in immune diseases such as autoimmunity, allergy and leukemia. Genes are housed in the nucleus of the cell, packaged into a structure known as chromatin. When the gene is not producing protein it is tightly packaged in chromatin but when it is activated to produce protein this packaging is altered to allow the gene to see the signals being received by the cell and produce protein. We have identified a protein within the nucleus that is critical in allowing certain cytokine genes to see the signals being received in the nucleus. By investigating the role of this protein (called c-Rel) in chromatin reorganization in immune cells, we hope to better define the steps required for appropriate gene activation in an immune response. This knowledge, in turn, will lead to the identification of novel therapeutic targets to control immune responsesRead moreRead less
Functional Analysis Of The P160 Myb-binding Protein - A Regulator Of Multiple Transcription Factors?
Funder
National Health and Medical Research Council
Funding Amount
$376,697.00
Summary
The c-myb gene is a key molecular regulator of normal blood cell production, but alterations to this gene can also lead to leukaemia. The protein (Myb) encode by the c-myb gene acts as a transcription factor, ie, it controls the activity of other genes. There is good evidence that interactions with other proteins can regulate the activity of Myb. Our laboratory has identified what we believe is one such protein - p160 - that binds to a part of Myb that reduces its activity, and thus that is like ....The c-myb gene is a key molecular regulator of normal blood cell production, but alterations to this gene can also lead to leukaemia. The protein (Myb) encode by the c-myb gene acts as a transcription factor, ie, it controls the activity of other genes. There is good evidence that interactions with other proteins can regulate the activity of Myb. Our laboratory has identified what we believe is one such protein - p160 - that binds to a part of Myb that reduces its activity, and thus that is likely to be responsible for regulating Myb. However, it has recently become apparent that p160 interacts with a number of other transcription factors in addition Myb. The primary aim of this project is to elucidate precisely how p160 interacts with Myb and what the consequences of this interaction are. A range of experimental approaches, which range from in vitro to genetic studies, will be employed to do this. We will test a specific role of p160 suggested by our preliminary studies - that of a transporter of transcription factors between the nucleus and the cytoplasm of the cell. Because of the wide range of transcription factors that p160 interacts with, its effects on the function of the cell are likely to be profound. For this same reason, it is difficult to specifically predict the possible medical-health implications of this work However, what we know to date is consistent with a role for p160 as a tumour suppressor gene. Moreover, parts of this project aim to generate genetic information and tools which will help in determining whether p160 does play such a role and generally, in identifying any other associations of p160 with particular diseases.Read moreRead less
Effects Of The Atrial Natriuretic Factor Enhancer And The 5'HS4 Insulator On The Probability Of Gene Expression.
Funder
National Health and Medical Research Council
Funding Amount
$534,628.00
Summary
Complex organisms contain many different types of cells, which can have completely different appearances and functions. All of these cells contain the same genes; the differences between them are achieved by the selective use of the genes. The means by which the selective use of genes is accomplished is a key to understanding how complex organisms develop, and how that development goes awry in cancer, heart disease, and other common disorders. A very large body of evidence indicates that gene re ....Complex organisms contain many different types of cells, which can have completely different appearances and functions. All of these cells contain the same genes; the differences between them are achieved by the selective use of the genes. The means by which the selective use of genes is accomplished is a key to understanding how complex organisms develop, and how that development goes awry in cancer, heart disease, and other common disorders. A very large body of evidence indicates that gene regulation is accomplished by the interaction of protein factors with segments of DNA flanking the gene. One hypothesis underlying our work is that the flanking DNA elements act primarily to increase the probability that a gene will be active rather than silent. We will ask if removing a known regulatory element from the gene for Atrial Natriuretic Factor (ANF) in mice reduces the likelihood of ANF being expressed by heart cells when the heart is stressed. This experiment will also shed new light on an extremely common disease state in humans (cardiac hypertrophy). In a second experiment, we will use a new experimental system we have developed to ask if a gene regulatory element is able to dial up the amount of expression from a gene, as well as to switch the gene on. Our previous work suggested this was not the case, but we wish to conduct a more rigorous test. Another hypothesis is that no DNA element is able to completely shield a transferred gene from the regulatory elements surrounding it. Accordingly, we will test a DNA element that has been proposed to insulate any gene from all influences of surrounding genes, and ask if it is able to create an autonomously expressing gene at any site within the genome. Because they deal with functions that are common to all genes, these experiments will provide information that should be applicable to a broad array of efforts to manipulate gene expression.Read moreRead less
Osteoporosis is a pathological loss of bone that affects many Australians. It occurs because of an excessive release of calcium from bone that is caused by the overactivity of the cells that break down bone, osteoclasts. We have studied two genes that are involved in the way these cells work and by a close examination of the the way they are regulated we hope to understand how osteoclasts are derived and how their activity is controlled. In particular we will look at two newly dicovered osteocla ....Osteoporosis is a pathological loss of bone that affects many Australians. It occurs because of an excessive release of calcium from bone that is caused by the overactivity of the cells that break down bone, osteoclasts. We have studied two genes that are involved in the way these cells work and by a close examination of the the way they are regulated we hope to understand how osteoclasts are derived and how their activity is controlled. In particular we will look at two newly dicovered osteoclast regulators called PPAR-gamma and PPAR-delta. These offer the opportunity for the development in the future of new, alternative drugs for the treatment of osteoporosis.Read moreRead less
All cells in the blood are the descendants of a single cell type, the stem cell. Stem cells are found in the bone marrow and throughout life have the unique ability to generate more of themselves (termed self-renewal) as well as to produce the functional cell types of the blood, ie. red and white blood cells. This project concentrates on the processes by which these stem cells can achieve these two functions. What are the genes that enable a stem cell to have this self-renewal characteristic and ....All cells in the blood are the descendants of a single cell type, the stem cell. Stem cells are found in the bone marrow and throughout life have the unique ability to generate more of themselves (termed self-renewal) as well as to produce the functional cell types of the blood, ie. red and white blood cells. This project concentrates on the processes by which these stem cells can achieve these two functions. What are the genes that enable a stem cell to have this self-renewal characteristic and conversely what are the genes that are activated when a cell becomes committed to become, for example, a white blood cell ? We have identified a gene, Pax5, which is essential in the process whereby a stem cell commits to become a lymphocyte . Our aim is to understand the function of Pax5 as a model for understanding how the commitment process as a whole works in the blood. These studies, as well as having an underlying fundamental scientific importance, are relevant to the clinical development of a number of stem cell therapies which rely on boosting stem cell production in procedures such as bone marrow transplantation for leukaemia and immune deficiency. In addition a number of characterised human blood malignancies indicate that inappropriate lineage commitment may be a factor in cancer.Read moreRead less