Cells recycle old components using a system called the proteasome. Some people are born without parts of the proteasome, and they suffer from a disease associated with inflammation. We have identified the molecular trigger for this inflammation. Our findings are also relevant for patients being treated with proteasome inhibitors. In some of these diseases, such as lupus, inflammation can be a side-effect of proteasome inhibitor therapy, and we can now reduce this and make the treatments safer.
Mechanism Of Proteotoxic Stress Induced Type I Interferon Signalling And Implications For Human Disease
Funder
National Health and Medical Research Council
Funding Amount
$322,952.00
Summary
All cells have a proteasome system to degrade unwanted proteins. Proteasome dysfunction causes a build-up of proteins that triggers, through an unknown mechanism, activation of the immune system leading to inflammation. People with mutations in genes which code for proteasome activity experience a severe disease known as Proteasome-Associated Autoinflammatory Syndrome. We aim to elucidate the link between protein aggregation and immune activation and employ this knowledge in disease treatment.
THE ROLE OF UBIQUITIN LIGASE ADAPTOR PROTEIN NDFIP1 IN NEURONAL DEVELOPMENT
Funder
National Health and Medical Research Council
Funding Amount
$581,813.00
Summary
Many brain diseases are characterized by faulty connections between nerve cells (neurons), in some cases caused by the inability to remove unwanted proteins from the neuron. This function is carried out by the ubiquitin-proteasome system (UPS). We have evidence that a UPS protein called Ndfip1 is important for forming functional brain circuits. We aim to discover whether neuron growth, branching and connectivity is promoted by Ndfip1 targeting of PTEN (phosphatase with tensin homology) to the UP ....Many brain diseases are characterized by faulty connections between nerve cells (neurons), in some cases caused by the inability to remove unwanted proteins from the neuron. This function is carried out by the ubiquitin-proteasome system (UPS). We have evidence that a UPS protein called Ndfip1 is important for forming functional brain circuits. We aim to discover whether neuron growth, branching and connectivity is promoted by Ndfip1 targeting of PTEN (phosphatase with tensin homology) to the UPS.Read moreRead less
Understanding The Mechanisms Of Substrate And Ubiquitin Lysine Specificity During Ubiquitination
Funder
National Health and Medical Research Council
Funding Amount
$573,993.00
Summary
Ubiquitin is a small molecule which controls all facets of a cell's growth and biology, such as growth. Ubiquitin functions by being attached to proteins in cells to alter their function and hence a particular chemical pathway. How ubiquitin is attached to proteins is poorly understood. This studiy will unveil how enzymes termed Ubcs attach ubiquitin to proteins, which is fundamental to understanding how ubiquitn controls cell functions.
Molecular Basis Of Artemisinin Action And Resistance In Plasmodium Falciparum
Funder
National Health and Medical Research Council
Funding Amount
$758,464.00
Summary
The malaria parasite, P. falciparum causes ~450,000 deaths each year. Resistance to the front-line antimalarial drug, artemisinin, is increasing, threatening at least another 100,000 lives per year, and potentially causing an additional ~A$500M in lost productivity. This project will identify the components of the parasite's cellular defence system that underpin resistance and will point to strategies for overcoming resistance to this important drug class.
Mechanisms Of Proteolysis Of Proteins Containing Oxidised Amino Acids
Funder
National Health and Medical Research Council
Funding Amount
$406,320.00
Summary
There is evidence that during ageing, and age-related diseases, proteins which have been chemically modified by oxidation accumulate in the body, and may have deleterious effects. Oxidation of proteins is a process akin to that by which fats go rancid. It has been demonstrated by the applicants to be an important process in formation of cataracts, and in development of the blood vessel disease, atherosclerosis, which is responsible for most heart attacks and stroke. Other important age-related d ....There is evidence that during ageing, and age-related diseases, proteins which have been chemically modified by oxidation accumulate in the body, and may have deleterious effects. Oxidation of proteins is a process akin to that by which fats go rancid. It has been demonstrated by the applicants to be an important process in formation of cataracts, and in development of the blood vessel disease, atherosclerosis, which is responsible for most heart attacks and stroke. Other important age-related diseases, such as Alzheimer s disease and other neurological disorders, are also claimed to be associated with deranged protein oxidation, and accumulation of oxidised products. There is clear evidence that certain defensive mechanisms, such as those acting to remove invading organisms and clear wounds, are also associated with an enhanced production of oxidised proteins. Perhaps the most important component of defense against oxidised proteins is their removal by complete breakdown to constituent components, and excretion. Normally, the machinery for breakdown of proteins is in vast excess over the required rate of degradation. However, clearly in these conditions of accumulation of oxidised proteins, this is no longer the case, or no longer suffices. Mechanisms by which oxidised proteins are degraded are poorly understood, and quite controversial. Therefore, the present studies bring to bear a new approach to studying this issue, which has been developed by the applicants. The aim is to reveal mechanisms involved in the breakdown of proteins containing oxidised amino acids, both in cellular systems, and in vivo. Such an understanding may allow us to envisage how to remove oxidised proteins by therapeutic means and therefore interfere with the development of age-related diseases such as Alzheimer s disease and cataract formation and the diseases of the blood vessels associated with attack and stroke.Read moreRead less
Characterisation Of The Antigen Cross-presentation Pathway In Dendritic Cells
Funder
National Health and Medical Research Council
Funding Amount
$593,888.00
Summary
T cells and Dendritic Cells (DC) are important components of the immune system. DC detect bacterial and viral infections and activate T cells to fight those infections. Our goal is to understand how DC communicate with T cells. This knowledge will allow us to develop new vaccines and to interfere with the mechanisms that enable infectious agents to escape detection.
Novel Mechanisms In Regulating Cytokine Secretion In The Inflammatory Response
Funder
National Health and Medical Research Council
Funding Amount
$323,160.00
Summary
Macrophages are key cells in the immune and inflammatory response. They play a role in many biological processes including wound healing and resistance to tumours and infections. It is also a major cell involved in mediating inflammation and tissue damage in chronic inflammatory diseases such as atherosclerosis and rheumatoid arthritis. The macrophage's role in these processes is achieved in large part by secreting enzymes and other proteins called cytokines to the outside of the cell. These cyt ....Macrophages are key cells in the immune and inflammatory response. They play a role in many biological processes including wound healing and resistance to tumours and infections. It is also a major cell involved in mediating inflammation and tissue damage in chronic inflammatory diseases such as atherosclerosis and rheumatoid arthritis. The macrophage's role in these processes is achieved in large part by secreting enzymes and other proteins called cytokines to the outside of the cell. These cytokines are synthesized by the macrophage and travel through a secretory pathway in the cell, in order to be released to the outside of the cell. There are various quality control mechanisms along the pathway which ensure only correctly made functional protein is secreted out of the cell. One cytokine, called macrophage inhibitory cytokine is produced by the immune cells called macrophages only when they become activated to mount an immune response against invading pathogens. The cell uses a novel mechanism to ensure the quality control of this cytokine. The propeptide of this cytokine targets incorrectly folded cytokine to a protein complex called the proteasome for degradation. This prevents secretion of inactive cytokine. Additionally, the propeptide of the cytokine helps secretion from macrophages by a novel mechanism. Because of these characteristics the cytokine provides a good model to study secretion from macrophages under pro- and anti-inflammatory conditions. In addition, demonstrating that activation of the macrophages causes a major upregulation in the synthesis and secretion of cytokines by novel mechanisms, will further our understanding of how the macrophage operates in fulfilling its role in the immune response.Read moreRead less
Systematically Exploring The Contribution Of Immunoproteasome To Immunodominance And T Cell Function
Funder
National Health and Medical Research Council
Funding Amount
$499,860.00
Summary
Vaccine will help us to fight both infectious diseases and malignancy. However, there are few successful vaccines for infectious agents and there is simply no vaccine to cure any tumor at the moment. So, it is essential for us to learn the basics related to vaccine development. Killer T cells eliminate tumour cells or virally infected host cells by recognising fragments (epitopes) derived from tumour- or virus-derived proteins displayed on a host molecule called MHC. Normally multiple epitopes a ....Vaccine will help us to fight both infectious diseases and malignancy. However, there are few successful vaccines for infectious agents and there is simply no vaccine to cure any tumor at the moment. So, it is essential for us to learn the basics related to vaccine development. Killer T cells eliminate tumour cells or virally infected host cells by recognising fragments (epitopes) derived from tumour- or virus-derived proteins displayed on a host molecule called MHC. Normally multiple epitopes are generated as part of the protein recycling program referred as proteine degradation which is mainly conducted by bundled enzyme complex, called proteasome. Two major forms of proteasomes are expressed by most cells. One called house-keeping proteasome and the other, which replaces the house-keeping one during viral infections is called immunoproteasome. The role that the immunoproteasome plays during anti-viral and anti-tumoral immune responses is not fully understood. In addition, the immunoproteasome is also expressed by a few cell types that do not suppose to need it if its function is entirely to generate better epitopes for MHC to display. In this project, we will sytematically explore the contribution of the immunoproteasome to overall anti-viral and anti-tumoral immune responses in three mouse model systems. The shared feature of these systems is that multiple killer T cell epitopes have been defined, which could potentially provide us with very sensitive assessments. The three systems are anti-influenza, anti-vaccinia virus and anti-tumor antigen (NY-ESO-1) mouse models.Read moreRead less