Exploring the gene regulation networks governing mitochondrial biogenesis in Arabidopsis. Mitochondria, subcellular organelles that perform many functions indispensable to plant growth and productivity, are dynamic compartments whose protein complement changes dramatically during plant development and under stress. Yet, the cellular processes that regulate the production of these organelles are virtually unknown. By combining conventional approaches with an extremely powerful holistic method for ....Exploring the gene regulation networks governing mitochondrial biogenesis in Arabidopsis. Mitochondria, subcellular organelles that perform many functions indispensable to plant growth and productivity, are dynamic compartments whose protein complement changes dramatically during plant development and under stress. Yet, the cellular processes that regulate the production of these organelles are virtually unknown. By combining conventional approaches with an extremely powerful holistic method for simultaneously examining the expression patterns of every gene in the model plant Arabidopsis, this project will identify proteins that regulate mitochondrial biosynthesis and uncover the gene networks that these proteins control. The project outcomes will provide new opportunities for the rational manipulation of plant growth and productivity.Read moreRead less
Genome Approaches to Investigate Metabolic Coordination in Plant Cells. Metabolism of C and N in legume nodules requires interaction between the symbiotic bacteria and plant organelles, particularly metabolism in plastids and mitochondria. Fixed N is assimilated through the de novo synthesis of purines in both plastids and mitochondria. However, each of the nine pathway enzymes is encoded by a single gene, indicating each protein is targeted to both organelles. Purine metabolism will provide ....Genome Approaches to Investigate Metabolic Coordination in Plant Cells. Metabolism of C and N in legume nodules requires interaction between the symbiotic bacteria and plant organelles, particularly metabolism in plastids and mitochondria. Fixed N is assimilated through the de novo synthesis of purines in both plastids and mitochondria. However, each of the nine pathway enzymes is encoded by a single gene, indicating each protein is targeted to both organelles. Purine metabolism will provide a model to assess the more general occurrence of dual-targeted proteins in plants. The aim is to identify and eventually exploit the signalling mechanism(s) that mediate communication between plastids and mitochondria.Read moreRead less
Functional Effects Of Polymorphic Variation Of The Aromatase (CYP19) Gene On Enzyme Activity:relationship To Disease
Funder
National Health and Medical Research Council
Funding Amount
$237,708.00
Summary
After menopause, oestrogen synthesis changes from an ovarian to an adipose source by concersion of androgens to estrogens, a process catalyzed by aromatase, the product of the CYP19 gene. We will generate mutants of the CYP19 gene that we have previously found in humans by site-directed mutagenesis and observe the effects of these mutants on aromatase function. This research will help with diagnosis and treatment of breast and other cancers and osteoporosis in humans .
Platelet Glycoprotein Proteolysis: Novel Mechanisms And Risk Factors
Funder
National Health and Medical Research Council
Funding Amount
$441,473.00
Summary
Platelets are the richest source of amyloid precursor protein (APP) in the body. Platelet ADAM10 regulates both the expression and function of the major platelet collagen receptor GPVI, and protective APP processing. Coagulation protein Factor X has a role in activation of ADAM10. This activation is disrupted in blood that has been treated with direct oral anticoagulant (DOAC) rivaroxaban. This grant will investigate the implications for people taking rivaroxaban on regulation of APP and GPVI.
Translocated signals regulating stem cell (meristem) activity in legumes. Translocation channels of phloem and xylem allocate nutrients to growing plant organs. They also mediate communication between organs through transport of signals that elicit responses to developmental and environmental cues. The most important sites for signal transduction are the stem cells of root and shoot apical meristems. This project will discover and identify these signals using a metabolomic/proteomic approach an ....Translocated signals regulating stem cell (meristem) activity in legumes. Translocation channels of phloem and xylem allocate nutrients to growing plant organs. They also mediate communication between organs through transport of signals that elicit responses to developmental and environmental cues. The most important sites for signal transduction are the stem cells of root and shoot apical meristems. This project will discover and identify these signals using a metabolomic/proteomic approach and relying on a unique feature of lupin that permits collection of transport fluids. The project will identify ways to modify signal action to enhance performance of legumes.Read moreRead less
The Role Of A Presenilin 2 Truncation (PS2V) In Alzheimer's Disease
Funder
National Health and Medical Research Council
Funding Amount
$552,741.00
Summary
The Presenilin and APP proteins are centrally important in inherited, early onset Alzheimer's disease. We have discovered that a shortened form of Presenilin protein, "PS2V", appears to increase specifically the rate at which the APP protein is cleaved to produce the "Amyloid beta" protein fragment that is found in Alzheimer's disease brains. This occurs when brain cells are under oxidative stress. Understanding this process will facilitate development of appropriate therapeutic strategies for t ....The Presenilin and APP proteins are centrally important in inherited, early onset Alzheimer's disease. We have discovered that a shortened form of Presenilin protein, "PS2V", appears to increase specifically the rate at which the APP protein is cleaved to produce the "Amyloid beta" protein fragment that is found in Alzheimer's disease brains. This occurs when brain cells are under oxidative stress. Understanding this process will facilitate development of appropriate therapeutic strategies for the disease.Read moreRead less
Examination Of The Molecular Pharmacology Of Anthracyclines Induced Via Their Interaction With Iron
Funder
National Health and Medical Research Council
Funding Amount
$618,401.00
Summary
Anthracyclines are highly effective anti-cancer drugs, but their use is limited by toxic effects on the heart. This is thought to be due to these drugs directly binding iron (Fe). Indeed, we showed that anthracyclines induced marked changes in the way heart cells utilise Fe (DR1-3, 38; Mol. Pharmacol. 2002, 2003, 2004, 2005). We were the first to show that anthracyclines prevent Fe release from the criticial Fe storage protein ferritin. This prevents the use of Fe for vital processes eg. DNA and ....Anthracyclines are highly effective anti-cancer drugs, but their use is limited by toxic effects on the heart. This is thought to be due to these drugs directly binding iron (Fe). Indeed, we showed that anthracyclines induced marked changes in the way heart cells utilise Fe (DR1-3, 38; Mol. Pharmacol. 2002, 2003, 2004, 2005). We were the first to show that anthracyclines prevent Fe release from the criticial Fe storage protein ferritin. This prevents the use of Fe for vital processes eg. DNA and haem synthesis. Hence, this effect probably contributes to the cytotoxic activity of anthracyclines on the heart. We showed that novel drugs developed in my lab that bind Fe called chelators show high activity in animals (DR4) and prevent anthracycline-mediated Fe accumulation in ferritin. Importantly, Fe chelators have been shown to inhibit anthracycline-mediated cardiotoxicity. Indeed, the clinically used cardioprotective agent, ICRF-187, is actually an Fe chelator (5, DR6). However, ICRF-187 is not totally successful in terms of its cardioprotective effects and can cause myelosuppression (5, DR6). While the clinically used chelator, desferrioxamine (DFO), can prevent anthracycline-mediated cardiotoxicity, its poor membrane permeability limits its effectiveness. Our chelators are highly permeable and overcome the disadvantages of DFO (DR4). Thus, they are vital to examine for preventing anthracycline-mediated cardiotoxicity. In this proposal we will examine the changes in Fe metabolism induced by anthracyclines and test the hypothesis that novel Fe chelators may prevent the cardiotoxicity of these agents. We also aim to be the first to assess if preparation of anthracyclines which cannot bind iron prevents their cardiotoxicity. This will be done by preparing metal complexes of these drugs which prevent Fe-binding eg. anthracycline-zinc complexes. These studies are important for the development of less cardiotoxic forms of these very useful anti-tumour agents.Read moreRead less
Understanding The Acute And Cumulative Metabolic Effects Of Prolonged Sitting In Adults
Funder
National Health and Medical Research Council
Funding Amount
$416,597.00
Summary
Sedentary behaviour (sitting time) has been linked to an increased risk of chronic illnesses, including type 2 diabetes and obesity, but recent evidence suggests that light-intensity activity (non-exercise activities of daily living) is associated with reduced risk. These studies will examine whether breaking up sitting time with frequent short periods of activity can overcome the negative effects of prolonged sitting on blood glucose and blood fats in overweight older adults.
Is transport of miRNAs essential for plant development? This project will provide knowledge of how a new class of biologically active molecule (micro RNA) regulates expression of genes at sites in the plant that are critical for growth and development. MicroRNAs are believed to influence the size and shape of plants, how rapidly they grow and how well they produce and fill seeds. These molecules are part of a group of bioactive signals that move throughout the plant, functioning like hormones bu ....Is transport of miRNAs essential for plant development? This project will provide knowledge of how a new class of biologically active molecule (micro RNA) regulates expression of genes at sites in the plant that are critical for growth and development. MicroRNAs are believed to influence the size and shape of plants, how rapidly they grow and how well they produce and fill seeds. These molecules are part of a group of bioactive signals that move throughout the plant, functioning like hormones but directly influencing how well critical genes work. Their exploitation holds great promise for manipulating plant performance and enhancing crop yields. Read moreRead less
The Role Of Gonadotropins In Regulating The Production Of Alzheimer's Beta Amyloid
Funder
National Health and Medical Research Council
Funding Amount
$400,278.00
Summary
Currently, about 160,000 Australians suffer from dementia; of which 50-70% are Alzheimer's disease (AD) cases. AD is characterised clinically by memory and personality changes and pathologically by deposition of amyloid. Of particular importance in the disease pathogenesis, is a small molecule called beta amyloid, of which the overproduction is thought to be central to the development of AD. Changes in the levels of the reproductive hormones, particularly low levels of oestrogen during menopause ....Currently, about 160,000 Australians suffer from dementia; of which 50-70% are Alzheimer's disease (AD) cases. AD is characterised clinically by memory and personality changes and pathologically by deposition of amyloid. Of particular importance in the disease pathogenesis, is a small molecule called beta amyloid, of which the overproduction is thought to be central to the development of AD. Changes in the levels of the reproductive hormones, particularly low levels of oestrogen during menopause or testosterone during andropuase, has been associated with the increased risk of developing AD and in altering the levels of beta amyloid. Furthermore, menopause and andropause are also characterised by changes in other reproductive hormones such as the gonadotropins. High levels of the gonadotropins have also been associated with the increased risk of developing AD. Therefore it is important to identify how these changes modify the risk of developing AD. This study examines the role of the gonadotropins in regulating beta amyloid levels in cell culture and in an animal model for AD. Furthermore, this study will assess, in the animal model, the use of gonadotropin lowering agents to reduce levels of beta amyloid. The results from this study will provide important data on how reproductive hormones regulate beta amyloid. Further insight into these mechanisms will provide therapeutic or preventative strategies for AD.Read moreRead less