Inactivation Of HERG Potassium Channels: Dynamic Changes In The Outer Pore Structure
Funder
National Health and Medical Research Council
Funding Amount
$422,716.00
Summary
Sudden cardiac death, due to disturbances in the normal electrical activity of the heart, is one of the leading causes of death in Australia and its incidence is increasing. Tackling the problem of cardiac arrhythmias is therefore one of the major challenges for cardiology in the 21st century. Two factors are greatly limiting progress in this area, the inability to predict who is most at risk and a paucity of treatment options. To address these problems, we need to better understand the basic me ....Sudden cardiac death, due to disturbances in the normal electrical activity of the heart, is one of the leading causes of death in Australia and its incidence is increasing. Tackling the problem of cardiac arrhythmias is therefore one of the major challenges for cardiology in the 21st century. Two factors are greatly limiting progress in this area, the inability to predict who is most at risk and a paucity of treatment options. To address these problems, we need to better understand the basic mechanisms underlying arrhythmias. The rhythm of the heart beat is controlled by electrical signals mediated by the flow of ions through specialised proteins called ion channels. Of the channels that contribute to cardiac electrical activity, potassium ion channels encoded by the Human ether-a-go-go-related gene (HERG) have been of particular interest for three reasons. Firstly, mutations in HERG are the cause of one third of cases of congenital long QT syndrome, an inherited cause of sudden cardiac death. Secondly, HERG is the molecular target for the vast majority of drugs that cause drug-induced long QT syndrome, the commonest cause of drug-induced arrhythmias and cardiac death. Thirdly, HERG channels have very unusual biophysical properties, which has led to the suggestion that they may act as an endogenous anti-arrhythmic agent . Accordingly, the major objective of the proposed research program is to understand the molecular and structural basis of the unusual properties of HERG channels. We will use a combination of molecular and electrical techiques in conjunction with computer modeling to probe the micoscopic motions in the channel that underly the unusual biophyscial properties of these channels. This work will facilitate a better understanding of how clinically identified mutations in HERG contribute to the increased risk of cardiac arrhythmias. More generally, it will improve our understanding of how cardiac ion channels maintain the normal rhythm of the heart.Read moreRead less
MEASURING AND MODELLING VISUAL CORTICAL PLASTICITY
Funder
National Health and Medical Research Council
Funding Amount
$612,693.00
Summary
We are the product of both our genes and our environment. Scientists have already shown that the physical structure of our brain can be changed by our experiences. But how much can it be changed? Our experiments will address this question for a particular case: how far our visual experiences can affect the structure of the part of our brain that processes visual images. This will help us understand the delicate balance between our genes and our environment in shaping who we are.
Investigation Of Biological Ion Channels: Theoretical Formulation, Computer Simulation And Experimental Verification
Funder
National Health and Medical Research Council
Funding Amount
$677,292.00
Summary
All electrical activities in the brain are regulated by opening and closing of ion channels. Thus, undertanding their mechanisms at a molecular level is a fundamental problem in neurobiology. There are many different types of ion channels, each type fulfilling a different role. For the first time, a group of American scientists have determined the shape of one type of ion channels. Using this newly unveiled information, we propose to build a mathematical theory of ion channels. And then, making ....All electrical activities in the brain are regulated by opening and closing of ion channels. Thus, undertanding their mechanisms at a molecular level is a fundamental problem in neurobiology. There are many different types of ion channels, each type fulfilling a different role. For the first time, a group of American scientists have determined the shape of one type of ion channels. Using this newly unveiled information, we propose to build a mathematical theory of ion channels. And then, making use of a powerful supercomputer, we propose to follow the motion of ions as they move through the channel, study how a channel can select only the correct type of ions to traverse it and determine how many ions a single channel is capable of processing per second. The predictions made by our theory and computer simulations will be checked experimentally. If the predictions and experimental findings do not agree, we will modify the theory and make new predictions.Read moreRead less