The Influence Of Alpha Actinins On Human Performance
Funder
National Health and Medical Research Council
Funding Amount
$542,500.00
Summary
There is a wide variation in skeletal muscle function in the general population. At one end of the spectrum are elite athletes who excel in a specialised area of sprint, power or endurance performance, while at the other end of the spectrum are individuals with muscle weakness due to inherited muscle disease. Part of this variation in human muscle performance is due to the genetic makeup of the individual. For example, world class sprinters have muscles which are genetically predisposed to gener ....There is a wide variation in skeletal muscle function in the general population. At one end of the spectrum are elite athletes who excel in a specialised area of sprint, power or endurance performance, while at the other end of the spectrum are individuals with muscle weakness due to inherited muscle disease. Part of this variation in human muscle performance is due to the genetic makeup of the individual. For example, world class sprinters have muscles which are genetically predisposed to generate maximal force at high speed. Similarly, the severity of muscle disease in an affected individual is influenced, in part, by other genes that affect normal muscle performance. The genes responsible for normal variations in muscle function in humans are unknown. The alpha-actinins are structural components of skeletal muscle. The two forms of alpha-actinin in skeletal muscle interact with a number of proteins involved in human muscle disease and thus likely contribute to the severity of muscle weakness in affected patients. Alpha-actinin-3 is present only in fast (type 2) fibres - the muscle fibres responsible for perfomance at high speed. We have identified a genetic change that results in absence of this protein in 1 in 5 people in the general population, without causing disease. We now have evidence that this genetic change, and hence whether or not muscle contains alpha-actinin-3, influences muscle performance in elite athletes. We will now use a variety of approaches to study the alpha-actinins in normal and diseased skeletal muscle. We will study the effect of changes (mutations) in the alpha-actinins in the muscle cells grown in the laboratory and in animal models. This work will impact on our understanding of how normal skeletal muscle functions, and the factors that influence human diversity in the general population.Read moreRead less
The maintenance of optimum health and function of living cells, and consequently that of the whole organism, depends on how cells respond to a multitude of physical and chemical stimuli that continually bombard them. The majority of the chemical stimuli such as hormones and neurotransmitters impart their actions not by directly entering the cell, but instead, by binding to a specific receiver protein at the cell surface called a receptor. In one class of such receptors called G protein coupled r ....The maintenance of optimum health and function of living cells, and consequently that of the whole organism, depends on how cells respond to a multitude of physical and chemical stimuli that continually bombard them. The majority of the chemical stimuli such as hormones and neurotransmitters impart their actions not by directly entering the cell, but instead, by binding to a specific receiver protein at the cell surface called a receptor. In one class of such receptors called G protein coupled receptors, the transmission of the message to the interior of the cell involves yet another protein called G protein. It is extremely important to unravel how each of these components, the stimulating agent, the receptor and G protein, works in order to understand how the cells respond to various chemical signals. To make this process even more complex, it was recently shown that another newly discovered group of proteins called receptor activity modifying proteins (RAMPs) too play a critical role in some systems. Understanding what actually is the role of these new players, and how they team-up with the other components to elicit a specific response to a chemical stimulus, forms the basis of this proposal. Such knowledge is central to the unraveling of the processes involved in the maintenance of health, abnormalities that lead to disease, and in the development of new treatments.Read moreRead less
Molecular Characterisation Of Receptor Activity Modifying Proteins (RAMPs)
Funder
National Health and Medical Research Council
Funding Amount
$340,399.00
Summary
The maintenance of optimum health and function of living cells, and consequently that of the whole organism, depends on how cells respond to a multitude of physical and chemical stimuli that continually bombard them. The majority of the chemical stimuli such as hormones and neurotransmitters impart their actions not by directly entering the cell, but instead, by binding to a specific receiver protein at the cell surface called a receptor. In one class of such receptors called G protein-coupled r ....The maintenance of optimum health and function of living cells, and consequently that of the whole organism, depends on how cells respond to a multitude of physical and chemical stimuli that continually bombard them. The majority of the chemical stimuli such as hormones and neurotransmitters impart their actions not by directly entering the cell, but instead, by binding to a specific receiver protein at the cell surface called a receptor. In one class of such receptors called G protein-coupled receptors, the transmission of the message to the interior of the cell involves yet another protein called G protein. These receptors are the most abundant type of cell surface receptors and form the targets for nearly 50% of currently used therapeutic drugs. It is, therefore, extremely important to unravel how each of these components works. To make this process even more complex, it was recently shown that another newly discovered group of proteins called receptor activity modifying proteins (RAMPs) too play a critical role in some systems. We have shown that RAMPs interact with many G protein-coupled receptors and that they have a wider range of actions than has previously been appreciated. Moreover, it has been shown that the RAMP-receptor interface is a viable target for drug development. Understanding the extent to which RAMPs interact with G protein-coupled receptors, how they interact with the receptors and the consequences of this interaction forms the basis of the current proposal. Such knowledge is central to the unraveling of the processes involved in the maintenance of health, abnormalities that lead to disease, and in the development of new treatments.Read moreRead less
The Influence Of Alpha Actinins On Human Performance In Health And Disease
Funder
National Health and Medical Research Council
Funding Amount
$480,989.00
Summary
We have identified a common genetic variation that results in absence of the fast muscle fibre protein, a-actinin-3, in over 1 billion people worldwide. Loss of a-actinin-3 influences elite athletic performance and skeletal muscle function in the general population by altering efficiency of muscle metabolism. We will now study mice and humans to determine how a-actinin-3 deficiency influences normal muscle function with age, response to exercise and the severity of human muscle disease.