The Structural Basis For The Control Of Cardiac And Skeletal Muscle By The Troponin Complex
Funder
National Health and Medical Research Council
Funding Amount
$369,003.00
Summary
Many key physiological processes are controlled by large, multi-protein complexes. These molecular machines ensure that signals transmitted in the body are correctly interpreted and amplified so as to control key body functions. The Troponin protein complex is one such large multi-protein complex which is the switch used to control both heart and skeletal muscle contraction in the body. The Troponin complex responds to increasing cellular calcium levels, switching the muscle on at high calcium. ....Many key physiological processes are controlled by large, multi-protein complexes. These molecular machines ensure that signals transmitted in the body are correctly interpreted and amplified so as to control key body functions. The Troponin protein complex is one such large multi-protein complex which is the switch used to control both heart and skeletal muscle contraction in the body. The Troponin complex responds to increasing cellular calcium levels, switching the muscle on at high calcium. When calcium returns to its normal basal level, the Troponin complex switches the muscle off. Naturally occurring genetic errors can lead to the malfunction of the Troponin complex. This, in turn, can lead to severe and possibly fatal diseases of the heart and muscle systems. To gain an understanding of these molecular diseases, it is important to understand the structure, dynamics and function of the Troponin complex. This project will use a newly-developed magnetic resonance method to monitor changes in the Troponin structure as a function of calcium level. Each component of the Troponin complex will be labeled with magnetic tags, allowing the determination of both structure and dynamics of Troponin, both in solution and in active muscle fibres. The study will result in a molecular understanding of how the Troponin switch works. This will give great insight in how mutations result in cardiac and muscular diseases.Read moreRead less
A Novel Patch-fluorimetry Technique For Investigating Structural Changes During Gating Of Mechanosensitive Ion Channnels
Funder
National Health and Medical Research Council
Funding Amount
$387,018.00
Summary
Membrane proteins, especially membrane channels play an important role in regulating the flow of substances across the cell. Dysfunction in these channels can lead to a variety of diseases. Thus approximately 60% of drug development is targeted against such proteins. In our research, we are looking at membrane channels found in bacteria. Understanding the function of these channels will help us develop novel anti-bacterial agents. It will also aid to understand a role of ion channels in disease.
Computational Study Of Selectivity, Gating And Mutation In The Acetylcholine Receptor And Potassium Channels
Funder
National Health and Medical Research Council
Funding Amount
$301,393.00
Summary
One way cells in living organisms communicate with each other is via the passage of charged particles across the cell membrane. This takes place through ion channels, large protein molecules that span the membrane and allow small molecules or ions to pass through a central pore. Malfunction of ion channels is known to underlie a variety of disorders including epilepsy, hypertension, kidney disease, heart attack, deafness. Channels also provide promising targets for making new broad spectrum anti ....One way cells in living organisms communicate with each other is via the passage of charged particles across the cell membrane. This takes place through ion channels, large protein molecules that span the membrane and allow small molecules or ions to pass through a central pore. Malfunction of ion channels is known to underlie a variety of disorders including epilepsy, hypertension, kidney disease, heart attack, deafness. Channels also provide promising targets for making new broad spectrum antibiotics and antivirals. This project aims to study two important types of ion channel: acetylcholine receptors that convey signals between nerve and muscle cells, and potassium channels that regulate the nerve impulses themselves. The binding of the neurotransmitter acetylcholine released from a nerve cell to acetylcholine receptors in the muscle cell prompts the opening of a cation conductive pore. The resulting influx of ions initiates a cascade of events ending in the contraction of the muscle fibre. However, the way in which this channel opening is initiated and how ions move into the muscle cell remain to be determined. Potassium channels are primarily used to rapidly 'switch off' nerve impulses so that subsequent messages can be passed through the nerve cell. To do this they have to be highly discriminatory, allowing only potassium to pass across the cell membrane and not sodium that would initiate another impulse. Although we now know what these tiny proteins look like, it is not clear how they differentiate between types of ions while still allowing many millions to pass each second. We will use computer simulations to study how these two type of channel open and close, and how they discriminate between different ion types. Using sophisticated computational techniques on Australia's most powerful supercomputers we aim to elucidate this fundamental area of human biology in the hope of deriving treatments for some debilitating neuromuscular diseases.Read moreRead less