Discovery Of Novel T Cell Oncogenes By Using A Functional Retroviral CDNA Library Screen.
Funder
National Health and Medical Research Council
Funding Amount
$692,470.00
Summary
T cells mature in an organ called the thymus which is located on top of the heart. Blood borne T cell precursors enter the thymus after being resident in the bone marrow. T cell leukaemia is a disease where a blood cell that is committed to becoming a T cell is blocked from maturing into a functional cell. Instead, the leukaemic immature T cell uncontrollably divides to make endless non-functional copies of itself. As a result, normal functional T cells are outcompteted and the immune system is ....T cells mature in an organ called the thymus which is located on top of the heart. Blood borne T cell precursors enter the thymus after being resident in the bone marrow. T cell leukaemia is a disease where a blood cell that is committed to becoming a T cell is blocked from maturing into a functional cell. Instead, the leukaemic immature T cell uncontrollably divides to make endless non-functional copies of itself. As a result, normal functional T cells are outcompteted and the immune system is crippled. Patients generally die due to opportunistic infection. The molecular causes of T cell leukaemia are slowly being discovered. Up to 50% of all human T cell leukaemias overexpress SCL-TAL-1. Other T cell leukaemia-causing genes (oncogenes) include Ras and Notch. Current leukaemia treatments include chemotherapy and bone marrow transplants but even these fail ~30% of the time. Consequently, all T cell oncogenes need to be discovered so that disease-specific treatments can be generated. This proposal will utlise a functional retroviral cDNA library screen to uncover novel T cell lineage commitment genes and T cell oncogenes. This will be accomplished by constructing a coloured [GFP] cDNA library (a library of genes) that will be transfected (inserted) into immature T cells that cannot develop down the T cell pathway owing to the lack of a crucial gene (Rag-1). The T cell oncogene Ras and the T cell lineage commitment gene Notch can move cells past the Rag-1 block. If there is a gene in the cDNA library that can compensate for the lack of Rag-1 and allow the cells to mature we will detect it using high speed flow cytometryic cell sorting (like sieving weevils from flour very quickly). Once we find this cell we will isolate the gene using the colour tag. The potential oncogenes uncovered will provide the foundation for next generation drug development that targets each leukaemia based on its cause.Read moreRead less
Cell death by a special process called apoptosis is a means of deleting unwanted and harmful cells from the body. Extensive apoptosis occurs during foetal development which is required to get rid of many excess cells produced during the growth of the embryo. Selective apoptosis is also essential for the formation of different tissues and organs in developing foetus. In the adult, apoptosis is required for proper functioning of the immune system, to remove virus infected and cancer cells and, in ....Cell death by a special process called apoptosis is a means of deleting unwanted and harmful cells from the body. Extensive apoptosis occurs during foetal development which is required to get rid of many excess cells produced during the growth of the embryo. Selective apoptosis is also essential for the formation of different tissues and organs in developing foetus. In the adult, apoptosis is required for proper functioning of the immune system, to remove virus infected and cancer cells and, in general, to maintain the correct number of cells in the body. As such, misregulation of apoptosis is associated with the pathogenesis of a wide array of diseases. To understand, manage and treat disorders that result from aberrant apoptosis, we need to know at molecular and cellular level, how apoptosis is brought about and how it is regulated. We have been studying these processes in detail for several years. Central to the apoptotic execution of cell death are a group of proteases called caspases, that target many cellular proteins for specific cleavage. The activation of caspases is the crucial step in the initiation of apoptosis and therefore each cell has developed complex ways to control this process. If we understand how these regulatory mechanisms operate, we can then formulate strategies that are targeted towards pathologies involving abnormal apoptosis. In this proposal we will use vinegar fly as a model to study the function of caspases in development. We believe that results from this proposal will have several major benefits. Firstly, they will provide important insight into the mechanisms of developmental apoptosis thereby filling many gaps in our current knowledge. Secondly, the study will endeavour to identify new molecules-pathways that lead to caspase activation. Finally, the proposed studies will shed light on the function of caspases in non-apoptotic pathways.Read moreRead less
Understanding how the brain grows and is organised is one of the great challenges of science. This project seeks to identify key regulators of neural progenitors as these are the building blocks from which all brains cells are derived. This knowledge may also identify new avenues through which to manipulate neural progenitor function. This has implications not only for normal brain development but also potential therapies for neural disorders and disease.
Defining The Role Of Nedd4 In Neural Crest Cell Development
Funder
National Health and Medical Research Council
Funding Amount
$541,565.00
Summary
Neural crest cells are specialised stem cells that give rise to many tissues and organs during embryonic development. We recently identified an essential role for a regulatory protein in neural crest cells. Our research is aimed at understanding how this protein influences the growth of structures such as the heart and facial skeleton. Understanding these processes underpins the ultimate goal of implementing diagnostic and preventative medicine for highly prevalent congenital birth defects.
Autophagy And Growth Signalling In Developmentally Programmed Cell Death
Funder
National Health and Medical Research Council
Funding Amount
$594,133.00
Summary
Cell death is essential for normal development and deregulated cell death results in many diseases. We have recently discovered a potentially novel mechanism of developmental cell death that involves autophagy (a type of self-degradation). Our studies will now examine the mechanism of autophagic cell death and study how cell growth regulation is integrated in this pathway. This will provide us important knowledge into the complex role of autophagy in cancer.
Microtubule Severing: A Role In Mammalian Oocyte And Embryo Viability?
Funder
National Health and Medical Research Council
Funding Amount
$620,251.00
Summary
In all cells, cell division is controlled by a microtubule based structure known as the spindle. Abnormal function of this spindle leads to loss and gain of chromosomes that in oocytes causes early embryo loss and in cells of the body it causes cancer and cell death. We will investigate a family of proteins that modify microtubules and explore the role they play in ensuring cell division happnens safely.
The Hippo Pathway, Neural Stem Cells And Brain Growth
Funder
National Health and Medical Research Council
Funding Amount
$363,137.00
Summary
During organism development, the brain grows to the right size without overgrowing. Neural stem cells are key regulators of brain size. We will define how the Hippo pathway crosstalks with nutrition-induced signals to control proliferation of neural stem cells and brain size. As well as producing important insights into normal growth, we will increase our understanding of brain diseases associated with aberrant brain growth, such as cancer.
Controlling The Pro-survival Protein Mcl-1: Discovering Novel Opportunities And Developing Innovative Approaches To Target Mcl-1 For Treating Cancers
Funder
National Health and Medical Research Council
Funding Amount
$749,415.00
Summary
Cancer cells are often sustained by evading cell death. Thus, a promising approach to develop new cancer treatments aims to restore their ability to commit cell suicide. Proteins related to Bcl-2 are, in this regard, attractive targets because they are prominent barriers to cell death. This project seeks to uncover how a Bcl-2 relative, Mcl-1, is regulated, and to explore how the mechanisms that underpin these processes can be targeted in cancers (melanomas, leukemias) that it sustains.
Evolutionary Conservation Of Caspase Regulatory Mechanisms
Funder
National Health and Medical Research Council
Funding Amount
$585,215.00
Summary
Apoptosis is a highly controlled process by which metazoans eliminate unwanted and dangerous cells. Dysregulation of apoptosis can contribute to many conditions including cancer, autoimmune and degenerative diseases. To develop therapeutic reagents that promote cell death when it fails to occur, or prevent it from happening inappropriately, it is necessary to understand the mechanisms controlling apoptosis. To date, many of the important insights into mammalian cell death signalling have been in ....Apoptosis is a highly controlled process by which metazoans eliminate unwanted and dangerous cells. Dysregulation of apoptosis can contribute to many conditions including cancer, autoimmune and degenerative diseases. To develop therapeutic reagents that promote cell death when it fails to occur, or prevent it from happening inappropriately, it is necessary to understand the mechanisms controlling apoptosis. To date, many of the important insights into mammalian cell death signalling have been informed by studies of apoptotic pathways in simpler, experimentally tractable model organisms. This project will exploit biochemical approaches and powerful yeast-based tools developed by CI-A to further explore cell death pathways of the nematode Caenorhabditis elegans, and compare these with mammalian apoptosis pathways. Key findings will be verified using genetic approaches. Most apoptotic stimuli ultimately kill mammalian, insect or nematode cells by triggering activation of proteases termed caspases. However, the mechanisms by which caspase activity is regulated appear to differ somewhat between mammals and worms. We will address two general possibilities: either these animals really do differ significantly in the upstream regulation of cell death pathways, or that functional counterparts of key components have not hitherto been identified or fully characterised. Understanding the way in which mammalian apoptosis is regulated will aid in the design of diagnostic and therapeutic reagents for the many diseases in which dysregulation of apoptosis has been implicated. This project seeks to define the extent to which apoptotic regulation is conserved between mammals and nematodes. This knowledge will enable researchers to maximise the utility of nematode cell death models for the further elucidation of mammalian cell death regulatory mechanisms, and to explore how apoptosis can be manipulated for clinical benefit.Read moreRead less
Determining The Role Of Rel/NF-kB Transcription Factors In Myeloid Differentiation
Funder
National Health and Medical Research Council
Funding Amount
$500,944.00
Summary
Different types of mature blood cells arise from stem cells in a process involving changes in gene expression that dictate which types of blood cells ultimately develop. A family of gene regulatory proteins called NF-kB transcription factors has been found to control the pattern of gene expression in a particular blood cell precursor called a granulocyte macrophage precursor (GMP) that normally generates two types of mature blood cells called macrophages and neutrophils. In the absence of NF-kB ....Different types of mature blood cells arise from stem cells in a process involving changes in gene expression that dictate which types of blood cells ultimately develop. A family of gene regulatory proteins called NF-kB transcription factors has been found to control the pattern of gene expression in a particular blood cell precursor called a granulocyte macrophage precursor (GMP) that normally generates two types of mature blood cells called macrophages and neutrophils. In the absence of NF-kB proteins, a change in the pattern of gene expression in GMPs leads to an imbalance in production of these two blood cell types that now favours the generation of neutrophils. This work will provide insight into the molecular mechanisms of blood cell development regulated by NF-kB. With disturbances in the balance of blood cell formation representing a hallmark of leukemia, understanding how this process is normally controlled may have important implications for developing therapeutic strategies to combat various types of leukemias.Read moreRead less