Defining The Role Of VEGF And Vascular Formation In Craniofacial Development
Funder
National Health and Medical Research Council
Funding Amount
$636,417.00
Summary
Aberrant neural crest cell development gives rise to common congenital malformations such as cleft lip and/or palate and cardiac outflow tract defects that effect over 1% of all births. As the aetiology of these disorders are largely unknown it is critical to understand the cell and molecular mechanisms coordinating NCC development such that alternative therapies may be devised to target the underlying pathological defects and to provide definitive diagnostic / prognostic tools.
Blimp-1: A Master Regulator Of B-lymphocyte Terminal Differentiation?
Funder
National Health and Medical Research Council
Funding Amount
$154,250.00
Summary
B lymphocytes are the antibody-producing cells of the immune system. They are formed in the bone marrow, and are exported to the body to circulate, searching for signs of infection. These circulating cells are not fully mature, but when they encounter an invader, with the help of other immune cells, they change. Most become antibody-producing cells, the final, operational cells of the B cell lineage. A few cells are set aside as memory cells that can rapidly become antibody-producing cells shoul ....B lymphocytes are the antibody-producing cells of the immune system. They are formed in the bone marrow, and are exported to the body to circulate, searching for signs of infection. These circulating cells are not fully mature, but when they encounter an invader, with the help of other immune cells, they change. Most become antibody-producing cells, the final, operational cells of the B cell lineage. A few cells are set aside as memory cells that can rapidly become antibody-producing cells should the same infection occur again. This is the basis of vaccination. The secretion of antibodies into the serum (that can bind to and eliminate an invader anywhere in the body) is the main function of B lymphocytes. This project will study the genes that allow B cells to become antibody-secreting cells (called ASC). We will focus on the gene for Blimp-1, the B lymphocyte-induced maturation protein, which has been called the master regulator of ASC formation. This claim is based largely on circumstantial evidence, and has not been directly tested genetically. We have made a mouse in which the Blimp-1 gene has been altered so that we can disable it in carefully controlled way. Using this knockout mouse, we can directly test the requirement for Blimp-1 in ASC and in other cell types. We will study these animals, using many tests that can accurately measure the behaviour of isolated cells, or the immune responses of the animals. We will examine other genes that are thought to be required for ASC to form or to perform their work, to see if loss of Blimp-1 (a known gene silencer) has impacted on these other genes. In this way, we expect to identify the genetic program that drives a B cell to become a mature ASC. Using this knowledge, we hope eventually to be able to study diseases of ASC in humans (as occur in allergy, asthma, rheumatoid arthritis and leukaemia). This information may also be used to improve the outcome of vaccination.Read moreRead less
Genetic Analysis Of Cell Death Pathways, Drug Resistance And Oncogenic Co-operativity In IL-3 Dependent Cell Lines
Funder
National Health and Medical Research Council
Funding Amount
$445,270.00
Summary
The ultimate fate of most of our cells is to die by committing suicide, because they are no longer required, are no longer functioning, or are potentially harmful. This normal physiological process is termed apoptosis . Inappropriate apoptosis can contribute to cell loss following heart attacks, stroke or neurodegenerative diseases, such as Alzheimer s or Parkinson s disease. Conversely, when cell death fails to occur, abnormal cells can accumulate and lead to cancer. In addition, because drugs ....The ultimate fate of most of our cells is to die by committing suicide, because they are no longer required, are no longer functioning, or are potentially harmful. This normal physiological process is termed apoptosis . Inappropriate apoptosis can contribute to cell loss following heart attacks, stroke or neurodegenerative diseases, such as Alzheimer s or Parkinson s disease. Conversely, when cell death fails to occur, abnormal cells can accumulate and lead to cancer. In addition, because drugs that are used to treat cancer may exert their effect by inducing apoptosis, a failure of this suicide response may cause resistance to chemotherapy. The genes of the apoptosis pathway function either to promote or inhibit cell death. We have found that some genes in the apoptosis pathway allow apoptosis to proceed rapidly, but do not decide the fate of the cell. Other genes are required for a cell to commit to die. If these genes are mutated then apoptosis does not occur and a functional cell may survive. The distinction between cells that decide fate and those that do not is crucial because it is only the genes that decide cell fate that can act as cancer genes, and are valid targets for therapy. We use a model in which apoptosis is caused by removal of a growth factor, using cell lines derived from mice that lack particular genes in the cell death pathway. These cells proliferate normally in the presence of growth factor, and allow us to determine the role of the genes when growth factor is withdrawn. Because these cells are sensitive to chemotherapeutic drugs, we can also determine the contribution these genes make to cancer drug sensitivity. Using this system, we have discovered that Puma, a gene known to be required for apoptosis in response to radiation, is also a critical activator of apoptosis following growth factor withdrawal. We will determine the manner in which Puma is regulated by growth factors, as well as identify and characterise other key components.Read moreRead less
Regulation Of Ribosomal Gene Transcription By C-MYC During Differentiation And Lymphomagenesis.
Funder
National Health and Medical Research Council
Funding Amount
$287,261.00
Summary
A fundamental question in medical biology revolves around how cells respond to the demands to grow and produce proteins, particularly in the setting of the rapid growth of cancer cells. One of the important facets of cellular growth is the production of new proteins needed for all areas of cell life. It is well known that cellular growth involves the production of proteins and this in turn requires the transcription or duplication of ribosomal RNAs (rRNAs). The control of rRNA synthesis, however ....A fundamental question in medical biology revolves around how cells respond to the demands to grow and produce proteins, particularly in the setting of the rapid growth of cancer cells. One of the important facets of cellular growth is the production of new proteins needed for all areas of cell life. It is well known that cellular growth involves the production of proteins and this in turn requires the transcription or duplication of ribosomal RNAs (rRNAs). The control of rRNA synthesis, however, is not well understood. We have identified a novel process to link a cancer causing gene c-MYC to the control of protein production in cells through regulation of rRNA synthesis. Our experiments will examine the hypothesis that c-MYC directly affects the production of rRNA . Finally we will test the link between the ability of c-MYC to cause malignant growth of cells and its role in increasing synthesis of rRNA. These findings may lay the basis for new treatments for disorders of regulated cell growth such as cancer.Read moreRead less
De-differentiation Of Committed Cells Into Haematopoietic Stem Cells By The Instructive Role Of The Transcription Factor HOXB4
Funder
National Health and Medical Research Council
Funding Amount
$683,040.00
Summary
Blood stem cells are long-lived and can give rise to every cell type of the blood system and due to these properties they are currently used in the clinics. Despite their importance, our knowledge of the mechanisms the control the multiplication of these rare cells is very scarce. This proposal aims to identify key factors that have the potential to convert mature, easy available blood cells into stem cells. This knowledge has to potential to lead to novel system that allow the expansion of stem ....Blood stem cells are long-lived and can give rise to every cell type of the blood system and due to these properties they are currently used in the clinics. Despite their importance, our knowledge of the mechanisms the control the multiplication of these rare cells is very scarce. This proposal aims to identify key factors that have the potential to convert mature, easy available blood cells into stem cells. This knowledge has to potential to lead to novel system that allow the expansion of stem cells for transplantations in the future.Read moreRead less
Revealing How Transcription Factors Search The DNA To Control Preimplantation Development In Mammals
Funder
National Health and Medical Research Council
Funding Amount
$605,251.00
Summary
The development of mammalian embryos relies on proteins that bind to DNA to activate different genes. While several proteins regulating genes during embryonic development have been identified, it remains unknown how these proteins find their specific DNA targets. We will apply new non-invasive methods to analyse the movement of DNA–binding proteins in intact mouse embryos undergoing normal development, and will determine the molecular mechanisms that control DNA–protein interactions.
Regulation Of TNF Expression In Inflammation And Cancer
Funder
National Health and Medical Research Council
Funding Amount
$728,447.00
Summary
By studying a spontaneous mutation in mice, we have found an error in the TNF gene (a major factor in many inflammatory diseases) that causes severe arthritis, heart valve disease and gut inflammation. We have also identified new regulators of TNF expression, which might be useful therapeutic targets to limit inflammation. We intend to study the role of these regulators in controlling the expression of TNF, and the link between chronic inflammation and the development of cancer.
Enrichment, Differentiation And Functional Analysis Of Growth Hormone Progenitor Cells From The Adult Mouse Pituitary
Funder
National Health and Medical Research Council
Funding Amount
$469,500.00
Summary
Many important bodily functions including growth, metabolism, onset of puberty, fertility, lactation and the ability to cope with stress are controlled by hormones secreted by the pituitary gland. Consequently, insufficient hormone production by the pituitary gland (hypopituitarism) results in life-threatening conditions which are a significant clinical problem. Growth Hormone (GH) deficiency is the most common form of pituitary hormone deficiency, affecting 1:3,500 individuals. Currently, GH de ....Many important bodily functions including growth, metabolism, onset of puberty, fertility, lactation and the ability to cope with stress are controlled by hormones secreted by the pituitary gland. Consequently, insufficient hormone production by the pituitary gland (hypopituitarism) results in life-threatening conditions which are a significant clinical problem. Growth Hormone (GH) deficiency is the most common form of pituitary hormone deficiency, affecting 1:3,500 individuals. Currently, GH deficiency is treated by daily injections of growth hormone at a cost of $30,000 to $50,000 per patient per annum. However, even with daily injections and despite the cost, it is difficult to mimic the naturally fluctuating hormone levels in the body, resulting in incomplete growth rescue. Long term injections also have severe side effects that can lead to cardiovascular problems, abnormal bone density, diabetes and cancers of various types. To overcome the disadvantages of hormone therapy we are investigating a new cell replacement therapy to treat GH deficiency. This approach requires knowledge about the mechanism by which GH-secreting cells are generated and maintained in the adult pituitary. For the first time, we have isolated a type of progenitor (unspecialised) cell from adult mouse pituitary that is capable of dividing and generating GH-secreting cells. Our current research aims to further purify these cells and to show that they are capable of secreting GH in response to biologically relevant signals. In addition, we will test whether these cells can grow and develop into functional cells when introduced into mice. In particular, we will test whether the progenitor cells can rescue dwarfism using a mouse model of GH deficiency. This pioneering study will provide the first insight into the possibility of cell therapy for the pituitary, and may ultimately lead to the development of better therapies for patients with GH deficiency.Read moreRead less