A NEW LOOK AT THE ROLE(S) OF GLYCOGEN AND SUGAR PHOSPHATES IN SKELETAL MUSCLE CONTRACTILITY
Funder
National Health and Medical Research Council
Funding Amount
$193,224.00
Summary
According to textbooks, glycogen in skeletal muscle is a homogenous molecular species whose sole role in muscle contraction is that of a carbohydrate-energy store. Likewise, sugar phosphates, such as glucose1-phosphate (G1-P), glucose 6-phosphate (G6-P), fructose 6-phosphate (F6-P) and fructose 1,6-bisphosphate (F1,6-bP) are generally presented as negatively charged compounds that act only as substrates-products of intermediary reactions in sugar degradation pathways. However, there is now compe ....According to textbooks, glycogen in skeletal muscle is a homogenous molecular species whose sole role in muscle contraction is that of a carbohydrate-energy store. Likewise, sugar phosphates, such as glucose1-phosphate (G1-P), glucose 6-phosphate (G6-P), fructose 6-phosphate (F6-P) and fructose 1,6-bisphosphate (F1,6-bP) are generally presented as negatively charged compounds that act only as substrates-products of intermediary reactions in sugar degradation pathways. However, there is now compelling evidence that (i) glycogen depletion impairs muscle contractility even when there is no shortage of cellular energy, (ii) there are two molecular forms of glycogen, and (iii) sugar phosphates can act as potent modifiers of functional domains in muscle proteins. This project addresses a number of novel questions regarding the role (s) of glycogen and sugar phosphates in muscle contractility and the cellular mechanisms involved. The knowledge produced will further our understanding of the correlation between Excitation-Contraction coupling and different intracellular glycogen pools, and of the molecular basis of prolonged effects of sugar phosphates on the contractile machinery. Furthermore, this work should also generate valuable insights into complex physiological (e.g. fatigue and aging) and pathological (e.g. atherosclerosis, metabolic myopathies) conditions which are still poorly understood.Read moreRead less
Approaches To Therapy For The Skeletal Muscle Actin Diseases
Funder
National Health and Medical Research Council
Funding Amount
$912,078.00
Summary
We have shown that errors in a crucial muscle protein called actin cause muscle diseases that affect newborn children. These diseases are mainly very severe, causing death within the first year of life. Currently there is no cure. This project will investigate possible therapies for these diseases, such as viral delivery of a normal version of actin and finding a drug to overcome the weakness. Successful outcomes will crucially bring treatment closer for the patients.
Functional Genomic Analyses Of Mitochondrial Disorders
Funder
National Health and Medical Research Council
Funding Amount
$577,001.00
Summary
Mitochondria produce most of the energy required by our bodies. Mutations in genes that make mitochondrial proteins cause mitochondrial dysfunction and lead to neurodegenerative and muscular diseases. We will identify mutations in mitochondrial genes in members of different Bulgarian and Gypsy families and discovery the mechanisms by which the mutations lead to disease.
Identifying Disease Genes For Neurogenetic Disorders Using Next Generation Sequencing
Funder
National Health and Medical Research Council
Funding Amount
$2,523,023.00
Summary
This project aims to identify novel disease genes, in other words, find genes, which have not previously been shown to cause human diseases when they are mutated. The collaborating laboratories on the project in Perth, Sydney, Melbourne and Boston, USA have a successful history in working together in finding human disease genes, harnessing, in the last few years, the now readily available power of next generation DNA sequencing to accelerate disease gene discovery.
The Effects Of ?-actinin-3 On Muscle Metabolism, Human Health And Disease
Funder
National Health and Medical Research Council
Funding Amount
$643,060.00
Summary
We have identified a common genetic variant that results in absence of the fast muscle fibre protein ?-actinin-3 in more than one billion humans worldwide. Loss of ?-actinin-3 influences elite athletic performance, muscle bulk and strength in the general population, response to diet and exercise, and susceptibility to obesity and developing type 2 diabetes. We have also demonstrated that ?-actinin-3 influence disease severity in a variety of inherited and acquired muscle disorders.
Molecular And Clinico-pathological Investigation Of Congenital Myopathies
Funder
National Health and Medical Research Council
Funding Amount
$743,290.00
Summary
Congenital myopathies are inherited disorders causing muscle weakness from birth. Some types lead to early death of the affected child, while others are compatible with life to adulthood. Like any disease of childhood, the congenital myopathies cause considerable trauma to the families concerned. Couples at risk of having another affected child frequently wait for prenatal diagnosis to become available for their particular disease before attempting to have further children. However, prenatal dia ....Congenital myopathies are inherited disorders causing muscle weakness from birth. Some types lead to early death of the affected child, while others are compatible with life to adulthood. Like any disease of childhood, the congenital myopathies cause considerable trauma to the families concerned. Couples at risk of having another affected child frequently wait for prenatal diagnosis to become available for their particular disease before attempting to have further children. However, prenatal diagnosis is only possible once the gene causing a disorder and the mutation in an individual family are identified. In the past, the Laboratories collaborating in this project, the Molecular Neurogenetics Laboratory, Australian Neuromuscular Research Institute, Perth, and the Neurogenetics Research Unit, New Children s Hospital, Sydney, have identified disease genes for congenital myopathies. Prenatal diagnosis is now possible for families whose disease-causing mutation is identified. However the genetic cause of many of the congenital myopathies remains unknown. DNA and other samples have been sent to the Laboratories from around the world, making us reference centres for congenital myopathy research. Part one of the project is to study these and Australasian samples, to identify other congenital myopathy genes. This will help families who currently cannot have prenatal diagnosis. Finding the genes also increases understanding of the diseases by clarifying which proteins are involved. In part two of the project we shall study the mutated proteins, to try to unravel how the gene mutations cause the diseases. The third part of the project is to reevaluate the highly variable muscle pathology in congenital myopathies in cases where the disease gene is now known, in order to investigate genotype-phenotype correlations. Understanding the pathologic basis of the congenital myopathies will ultimately allow us to begin to think rationally about possible treatments.Read moreRead less