Structure-function Inter-relationships Of Small Heat-shock Chaperone Proteins
Funder
National Health and Medical Research Council
Funding Amount
$240,990.00
Summary
In vivo, most proteins only function over a narrow temperature or pH range. For example, if the solution containing a particular protein is heated (stressed), the protein will unfold, aggregate and potentially precipitate. The act of protein precipitation is an irreversible process that, in many cases, has deleterious consequences for cell viability. Protein precipitation is associated with a diversity of diseases, e.g. cataract and neurodegenerative diseases such as Alzheimer's, Creutzfeldt-Jak ....In vivo, most proteins only function over a narrow temperature or pH range. For example, if the solution containing a particular protein is heated (stressed), the protein will unfold, aggregate and potentially precipitate. The act of protein precipitation is an irreversible process that, in many cases, has deleterious consequences for cell viability. Protein precipitation is associated with a diversity of diseases, e.g. cataract and neurodegenerative diseases such as Alzheimer's, Creutzfeldt-Jakob and Parkinson's diseases. Nature has evolved cellular mechanisms to minimise protein misfolding, aggregation and precipitation which principally utilise a diverse group of controlling or regulatory proteins called molecular chaperones. Amongst the most important of these are the small heat-shock proteins (sHsps) which are found in all organisms. sHsps function by interacting in a very efficient manner with destabilised proteins to prevent their precipitation. Little is known, however, about the structure of sHsps nor the mechanism by which they perform their chaperone action. This proposal will address these fundamental aspects via the use of a variety of spectroscopic techniques, principally nuclear magnetic resonance (NMR) spectroscopy.Read moreRead less
Structural Characterisation Of Phosphopeptide Recognition By FHA Domains
Funder
National Health and Medical Research Council
Funding Amount
$257,036.00
Summary
Cells require numerous signalling pathways to keep various cellular processes coordinated and under control. One of the most important aspects of signalling is formation of complexes involving two or more different proteins. One of the recently identified players in the formation of these signalling complexes is the so-called forkhead-associated (FHA) module, FHA modules are protein sequences of ~130 amino acids that appear as a part of signalling proteins and bind to specific sequences on signa ....Cells require numerous signalling pathways to keep various cellular processes coordinated and under control. One of the most important aspects of signalling is formation of complexes involving two or more different proteins. One of the recently identified players in the formation of these signalling complexes is the so-called forkhead-associated (FHA) module, FHA modules are protein sequences of ~130 amino acids that appear as a part of signalling proteins and bind to specific sequences on signalling protein partners. Many proteins containing FHA modules are important for the repair of damaged DNA and the stability of chromosomes. The aim of our studies is to understand the molecular and atomic details of how FHA modules bind their partners. This is the first step towards designing therapeutic agents against various forms of cancer where DNA is damaged.Read moreRead less
To Investigate The Role Of ATM Protein In Protecting Against Neurodegeneration
Funder
National Health and Medical Research Council
Funding Amount
$953,662.00
Summary
The overall aim of the project is to employ a rat model to investigate neurodegeneration in patients with ataxia-telangiectasia (A-T). Ataxia-telangiectasia is a complex multisystem disorder characterised by progressive neurological impairment, variable immunodeficiency and cancer predisposition. The rat model recapitulates the neurodegeneration in patients and thus this project will provide important insight into the nature of the defect as well as approaches for the treatment of the disorder.
Development Of Iron Chelators For The Treatment Of Friedreichs Ataxia And The Role Of Frataxin In Iron Metabolism
Funder
National Health and Medical Research Council
Funding Amount
$550,987.00
Summary
Friedreich's ataxia (FA) is a neuro- and cardio-degenerative disease where there is an accumulation of toxic Fe in the mitochondrion. Excitingly, work from our current NHMRC grant showed iron plays a significant role in FA pathology. Importantly, we developed new drugs (Fe chelators) which rescue the cardiac pathology of FA in an animal model. Studies will now assess if our drugs prevent the neurodegeneration of FA in another animal model. This work could lead to novel therapies for FA.
Mitochondrial Iron Overload And Friedreich's Ataxia: The Role Of Frataxin In Iron And Haem Metabolism
Funder
National Health and Medical Research Council
Funding Amount
$606,000.00
Summary
Friedreich's ataxia (FA) is due to the lack of a protein known as frataxin. A variety of studies using Baker's yeast and conditional frataxin knockout (KO) mice have shown that deletion of frataxin leads to the accumulation of toxic iron in their mitochondrion. More recently, a variety of studies have shown that FA patients have iron-loading within their mitochondrion. Iron in the highly redox active environment of the mitochondrion could contribute to the generation of cytotoxic radicals that c ....Friedreich's ataxia (FA) is due to the lack of a protein known as frataxin. A variety of studies using Baker's yeast and conditional frataxin knockout (KO) mice have shown that deletion of frataxin leads to the accumulation of toxic iron in their mitochondrion. More recently, a variety of studies have shown that FA patients have iron-loading within their mitochondrion. Iron in the highly redox active environment of the mitochondrion could contribute to the generation of cytotoxic radicals that cause severe damage. Further, cells deficient in frataxin are sensitive to oxidant stress and Fe chelators rescue oxidant-mediated death of cells from FA patients. Indeed, free radical scavengers have shown to be of use in the treatment of this disease. Studies in DR's lab during this NHMRC grant have shown that frataxin is down-regulated by erythroid differentiation or the haem precursor, protoporphyrin IX (BLOOD 2002;99:3813-22). These data indicate a role for frataxin in Fe metabolism and the pathogenesis of FA. In this study we will continue to examine the role of frataxin in the way cells handle Fe using experimental models developed under the current NHMRC grant. These include transfected cell lines with low frataxin expression generated using an expression vector containing anti-sense frataxin cDNA. Further we obtained the frataxin conditional KO mouse and generated a breeding colony. These animals display many of the pathological features of FA and are the best current model of the disease. Indeed, they will be critical for assessing the role of frataxin in Fe metabolism and as a model to test the ability of Fe-binding drugs to prevent the pathology observed. We designed lipid-soluble chelators that can enter the mitochondrion to bind Fe (Biochim Biophys Acta 2001;1536:133-140) and these ligands will be tested to prevent disease progression in the KO mice. This exciting research is crucial for understanding the pathogenesis of FA and in creating new therapies.Read moreRead less
Pathogenic Repeat Expansions In Ataxia: Advancing Gene Discovery And Genetic Diagnosis
Funder
National Health and Medical Research Council
Funding Amount
$645,205.00
Summary
Hereditary ataxia is a severe neurological disorder that results in impaired coordination and balance and affects 1 in 20,000 Australians. Ataxias are often caused by complex genetic mutations called repeat expansions (RE), which are difficult to detect. Therefore, genetic diagnosis of ataxia remains limited and poorly accessible, leading to a gap in clinical care. In this study, we will utilise modern advances in genetic sequencing technology to diagnose and discover ataxias caused by REs.