Molecular Basis Of Ca2+-dependent Disruption Of EC-coupling And Weakness In Skeletal Muscle
Funder
National Health and Medical Research Council
Funding Amount
$530,976.00
Summary
One major cause of weakness in skeletal muscle appears to stem from damage to the mechanism controlling release of calcium ions from internal stores and consequent contraction. This project examines whether the damage is due to excessive levels of intracellular calcium ions activating enzymes that cut a particular vital molecule controlling calcium release. The findings could identify a major factor in muscle weakness in muscular dystrophy and other conditions and lead to specific therapies.
Role Of Nitric Oxide And Reactive Oxygen Species In Excitation-contraction Coupling In Skeletal Muscle.
Funder
National Health and Medical Research Council
Funding Amount
$163,250.00
Summary
Excitation-contraction (E-C) coupling is a term used to broadly describe the sequence of cellular events that starts with an electrical signal at the surface membrane of a muscle cell and which then ultimately leads to muscle contraction. Although the overall sequence is known, there remain many gaps in our understanding of the mechanisms involved not only related to normal muscle function but to how this function may be impaired by excessive exercise and disease. Many cellular metabolites contr ....Excitation-contraction (E-C) coupling is a term used to broadly describe the sequence of cellular events that starts with an electrical signal at the surface membrane of a muscle cell and which then ultimately leads to muscle contraction. Although the overall sequence is known, there remain many gaps in our understanding of the mechanisms involved not only related to normal muscle function but to how this function may be impaired by excessive exercise and disease. Many cellular metabolites contribute towards the normal control of muscle contraction, while others contribute to its impairment. Reactive oxygen species (ROS), which includes nitric oxide (NO) and related molecules, are metabolic factors often referred to as cellular oxidants. They are thought to have an essential role in controlling normal muscle function. Paradoxically, they are also implicated in the impairment of muscle function associated with fatigue, disease and aging. How these molecules both control normal muscle activity and also contribute to impairment of such function remains unclear. Thus, the central aim of this project is to identify the mechanisms by which the cellular oxidants, NO and other ROS, both control normal E-C coupling in skeletal muscle fibres and how they contribute to muscle fatigue. Clearly, understanding how skeletal muscle normally contracts is essential in order to better understand how muscle function can become impaired with exercise, disease and age. The work from this study will provide insight into both normal muscle physiology and how muscles fatigue and ultimately provide new methodologies and drugs that may combat fatigue, disease and age related changes to muscle function.Read moreRead less
DHPR ? Subunit Binding To A Variably Spliced Region Of RyR1: A Role In EC Coupling And Myotonic Dystrophy
Funder
National Health and Medical Research Council
Funding Amount
$555,892.00
Summary
We have uncovered a communication pathway between two ion channel molecules in muscle cells that underlies human movement. The pathway is critical in normal mobility and is disrupted in myotonic dystrophy. We will study the molecular components of this pathway to understand normal body function and abnormal function in mytotonic dystrophy. The work will facilitate the design of drugs to relieve the mytotonic dystrophy myopathy and form new and much needed class of specific muscle relaxants.
Many human muscle diseases are caused by mutations in genes encoding skeletal muscle actin. Actin is a major building block of the sarcomere, the engine of muscle contraction. Our studies have identified a mutation in chaperonin, the main protein-folding complex responsible for actin folding, which results in a muscle defect. These results have led to a novel hypothesesis, which we test in this grant, namely that as the chaperonin complex can act as a modulator of of muscle disease.
Decrypting The Excitation Contraction Coupling Machinery In Skeletal Muscle
Funder
National Health and Medical Research Council
Funding Amount
$914,869.00
Summary
Skeletal muscle function is dependent upon the fine control of calcium levels. When communication of key proteins in muscle are compromised, calcium levels are uncontrolled leading to severe disabilities. The molecular pathways that control signalling between key muscle proteins is currently unknown and shedding light on this topic will aid in the discovery of therapies for muscle-associated disabilities in disease and with aging.