Genetic Variation Of Mitochondrial Complex I: Its Role In Rare And Common Diseases
Funder
National Health and Medical Research Council
Funding Amount
$628,415.00
Summary
Our bodies convert food into energy in tiny cellular power plants called mitochondria. Each year about 50 Australian children inherit disorders of mitochondrial energy generation. The most severe disorders cause infant death, while others cause degenerative diseases in later life, particularly affecting brain and muscle. In most cases we lack effective treatments. The genetic causes of mitochondrial disorders are incredibly diverse, with over 70 disease genes known. Some are located on the uniqu ....Our bodies convert food into energy in tiny cellular power plants called mitochondria. Each year about 50 Australian children inherit disorders of mitochondrial energy generation. The most severe disorders cause infant death, while others cause degenerative diseases in later life, particularly affecting brain and muscle. In most cases we lack effective treatments. The genetic causes of mitochondrial disorders are incredibly diverse, with over 70 disease genes known. Some are located on the unique mitochondrial DNA we inherit only from our mothers. Many more genes await discovery. This grant focuses on the most common energy generation disorder, known as Complex I deficiency. Complex I requires 46 separate components to be assembled together in order to work properly, but mutations in the 46 genes encoding these components only seem to explain disease in about half of all patients. Our aim is to identify new disease genes and to determine whether some patients have mutations in two different genes that interact to cause disease, rather than in a single gene. We will use a number of methods to pinpoint where in the genome the causative genes are located and then home in on the exact changes in the genes that cause disease. Identifying these genes will allow us to improve future diagnosis and prevention of mitochondrial disease. We will also generate mice in which one of the Complex I genes has been knocked out. These mice will allow us to better understand the basic disease mechanisms that link gene changes to disease. Understanding the basic biology may allow us to develop new methods of treatment. The mouse models will also be useful for trialling new treatments and for investigating the role of milder mitochondrial problems in common diseases such as diabetes and Parkinson disease. Any new treatments could potentially have wide application.Read moreRead less
Identifying Novel Genes Causing Cytochrome C Oxidase (COX) Deficiency
Funder
National Health and Medical Research Council
Funding Amount
$426,917.00
Summary
Our bodies convert food into energy in tiny cellular power plants called mitochondria. Each year about 50 Australian children inherit disorders of mitochondrial energy generation. The most severe disorders cause infant death, while others cause degenerative diseases in later life, particularly affecting brain and muscle. In most cases we lack effective treatments. The genetic causes of mitochondrial disorders are incredibly diverse, with over 70 disease genes known. Some are located on the uniqu ....Our bodies convert food into energy in tiny cellular power plants called mitochondria. Each year about 50 Australian children inherit disorders of mitochondrial energy generation. The most severe disorders cause infant death, while others cause degenerative diseases in later life, particularly affecting brain and muscle. In most cases we lack effective treatments. The genetic causes of mitochondrial disorders are incredibly diverse, with over 70 disease genes known. Some are located on the unique mitochondrial DNA we inherit only from our mothers. Many more genes await discovery. This study focuses on the mitochondrial disorder cytochrome c oxidase (COX) deficiency, for which we have diagnosed 80 Australian patients. COX requires 13 separate components to be assembled together in order to work properly, but mutations in the genes encoding these components are not present in most patients. We believe that the most common problems will be in genes involved in assembling the components rather than in the components themselves. We will use a number of methods to pinpoint where in the genome the disease genes are located. A key to our strategy is identifying patients likely to have mutations in the same gene. We have identified two such groups, and will do studies that involving fusing two cell lines together to confirm they have the same disorder. We will then perform genetic mapping to look for regions of similarity in the genome using DNA (SNP) chips. We will test how well the genes in such regions are expressed, whether we can correct the problem in cultured skin cells by introducing a healthy copy of that chromosome, and look for gene mutations. Identifying these genes will allow us to improve future diagnosis and prevention and may allow us to develop new methods of treatment. Milder mitochondrial problems also contribute to a range of more common diseases such as diabetes and Alzheimer disease, so any new treatments could potentially have wide applicationRead moreRead less
Functions Of A Novel Conserved DNA Damage Response Protein Family In Telomere Stability
Funder
National Health and Medical Research Council
Funding Amount
$282,825.00
Summary
The free DNA ends of chromosomes, termed telomeres, generally resemble broken DNA. Because broken DNA is a major contributing factor to the onset of cancer, cells try to fix broken ends. However, in case of telomeres, such repair processes have to be prevented because otherwise different chromosomes would fuse with each other. Fused chromosomes are very fragile and cannot be evenly distributed between dividing cells, and are therefore another important trigger of cancer development. Therefore, c ....The free DNA ends of chromosomes, termed telomeres, generally resemble broken DNA. Because broken DNA is a major contributing factor to the onset of cancer, cells try to fix broken ends. However, in case of telomeres, such repair processes have to be prevented because otherwise different chromosomes would fuse with each other. Fused chromosomes are very fragile and cannot be evenly distributed between dividing cells, and are therefore another important trigger of cancer development. Therefore, chromosome ends are covered by a cap, which hides them from the DNA damage response machinery. From these considerations it is clear that there are close connections between the cellular DNA damage response and chromosome ends. Moreover, recently it has become clear that DNA damage proteins are also required to stop normal cells from growing, a process termed senescence. Senescence is a consequence of shortened chromosome ends, and does not occur in cancer cells. Altogether, it is clear that DNA breaks and senescence are two of the major questions for our understanding of cancer development. We have identified a novel conserved protein family that is involved in the response to DNA damage in yeast and humans. In addition, the yeast Mdt1 protein is a very sensitive indicator of changes in the telomere cap. Absence of proteins that organise the cap leads to the addition of several phosphate groups to the Mdt1 protein. We propose that phosphate-coupled Mdt1 prevents chromosome ends from fusion with each other, or from fusing with broken DNA ends after widespread damage. As a consequence, cells that have mild cap defects die at an >1000-fold increased rate in response to DNA damage when they also lack Mdt1. As part of this application we want to find out the precise mechanism by which Mdt1 stabilises chromosome ends, and test our hypothesis that the corresponding human protein termed ASCIZ also has similar functions in protecting chromosome ends.Read moreRead less
The genomics of adaptation in Wolbachia pipientis, an emerging biocontrol agent. Australians are increasingly exposed to insect-transmitted diseases such as dengue fever. Novel biocontrol methods using the bacterium Wolbachia aim to control insect populations to reduce disease transmission. Our research will be the first to investigate genomic variation and the process of adaptation to new insect hosts in Wolbachia. The novel data and understanding of evolutionary processes we generate will be c ....The genomics of adaptation in Wolbachia pipientis, an emerging biocontrol agent. Australians are increasingly exposed to insect-transmitted diseases such as dengue fever. Novel biocontrol methods using the bacterium Wolbachia aim to control insect populations to reduce disease transmission. Our research will be the first to investigate genomic variation and the process of adaptation to new insect hosts in Wolbachia. The novel data and understanding of evolutionary processes we generate will be critical for screening bacterial biocontrol candidates and designing biocontrol release strategies. It will also strengthen the position of Australian research as a world-leader in the fusion of post-genomics and applied microbiology. Read moreRead less
A comparative genomics approach to understanding host-endosymbiont interactions. Australia's unique ecosystems are vulnerable to invasion by exotic pests that threaten agriculture and human health. The bacterial symbiont Wolbachia is found in many major pests of agricultural and medical importance. Our results will give insights into how Wolbachia spreads into host populations and improve its use as a tool to impair insect transmission of disease, e.g. as an agent to carry genes into an insect p ....A comparative genomics approach to understanding host-endosymbiont interactions. Australia's unique ecosystems are vulnerable to invasion by exotic pests that threaten agriculture and human health. The bacterial symbiont Wolbachia is found in many major pests of agricultural and medical importance. Our results will give insights into how Wolbachia spreads into host populations and improve its use as a tool to impair insect transmission of disease, e.g. as an agent to carry genes into an insect population that limit disease transmission. Our results will also make fundamental contributions to understanding host-parasite evolution, host-parasite communication, and insect developmental processes, and will be of interest to a large international community of researchers in this field. Read moreRead less
Diseases Of Aminoacid Transport: Genetic, Molecular And Biochemical Studies
Funder
National Health and Medical Research Council
Funding Amount
$394,173.00
Summary
Aminoacids are essential building blocks of all living things. They are taken up and retained in the body by highly specific pumps on the surface of cells. By understanding the mechanisms that control aminoacids, we will not only uncover pathways common to normal biology but also shed light on mechanisms of disease in humans. Specifically, the aminoacidurias include a number of inherited diseases of aminoacid transport that result in failure of uptake and retention of particular aminoacids. Hart ....Aminoacids are essential building blocks of all living things. They are taken up and retained in the body by highly specific pumps on the surface of cells. By understanding the mechanisms that control aminoacids, we will not only uncover pathways common to normal biology but also shed light on mechanisms of disease in humans. Specifically, the aminoacidurias include a number of inherited diseases of aminoacid transport that result in failure of uptake and retention of particular aminoacids. Hartnup disease is an inherited disorder of neutral aminoacid transport that can lead to a sun-sensitive skin rash, difficulties in controlling movements and walking and other neurological symptoms including mental retardation. A major feature of Hartnup disease is its clinical variability. We have recently identified the main genetic cause for Hartnup disease, and named the gene SLC6A19. We wish to examine whether the clinical variability observed is a consequence of genetic changes and variability in SLC6A19 and other possible genes. Two other aminoacidurias to be studied are dicarboxylic aminoaciduria and iminoglycinuria; both of which are also variable in their clinical consequences ranging from normality to mental retardation. Owing to the relative rarity of these disorders, we are fortunate to have exclusive access to individuals identified by the largest neonatal screening programme for aminoacidurias in the world, based in Canada, and other clinical cohorts within Australia. We will undertake genetic testing to localise and-or confirm the gene(s) involved in these diseases for the first time anywhere and then seek to explain their clinical variability based on functional analyses. We have established a team of researchers with complementary skills from three sites comprising the Australian Aminoaciduria Consortium. Outcomes from this project should impact on the causes and possible therapies for other important medical diseases including motor neurone disease.Read moreRead less
Australian Laureate Fellowships - Grant ID: FL200100068
Funder
Australian Research Council
Funding Amount
$3,328,974.00
Summary
Australian wild animals: environmental change and quantitative genomics. This project aims to determine the effects of changing environments on wild animal populations across Australia. By combining recent advances in genomic technology with a consortium of fourteen long-term studies of mammals, birds and reptiles, it aims to quantify the genetic basis of life-history variation and the potential for evolutionary adaptation in the wild. The project will generate a comprehensive understanding of t ....Australian wild animals: environmental change and quantitative genomics. This project aims to determine the effects of changing environments on wild animal populations across Australia. By combining recent advances in genomic technology with a consortium of fourteen long-term studies of mammals, birds and reptiles, it aims to quantify the genetic basis of life-history variation and the potential for evolutionary adaptation in the wild. The project will generate a comprehensive understanding of the genetic consequences of environmental change, population decline, inbreeding and disease in natural environments. The expected benefits include a coordinated network for long-term wild animal studies in Australia, advanced quantitative skills training, and knowledge transfer for wildlife management and conservation.Read moreRead less
Discovery Early Career Researcher Award - Grant ID: DE210100549
Funder
Australian Research Council
Funding Amount
$417,328.00
Summary
Adaptive evolution and its demographic consequences today. This project aims to provide the first test of whether the rate of adaptative genetic evolution has changed in the recent decades, to quantify how much recent genetic evolution helps animal populations survive, and to increase the ability to study on-going genetic evolution in Australian wildlife. The project is of major significance as many species are currently threatened, or invading, due to rapid environmental changes, in particular ....Adaptive evolution and its demographic consequences today. This project aims to provide the first test of whether the rate of adaptative genetic evolution has changed in the recent decades, to quantify how much recent genetic evolution helps animal populations survive, and to increase the ability to study on-going genetic evolution in Australian wildlife. The project is of major significance as many species are currently threatened, or invading, due to rapid environmental changes, in particular climate change. The anticipated outcome of the project is to deliver new methods, establish a network of international and national collaborators and improve the ability to measure and to forecast how Australian animals adapt to rapidly changing environments.Read moreRead less