Characterisation of the oxygen-sensing asparaginyl hydroxylase, FIH-1, and hydroxylase-specific antagonists. This research will provide fundamental information on how cells and whole organisms can sense and respond accordingly to oxygen deficiency. This information is fundamental for our understanding of embryo development and adult life in different environments, and central to the diagnosis and treatment of diseases such as stroke, cardiovascular disease, and cancer. This research will contrib ....Characterisation of the oxygen-sensing asparaginyl hydroxylase, FIH-1, and hydroxylase-specific antagonists. This research will provide fundamental information on how cells and whole organisms can sense and respond accordingly to oxygen deficiency. This information is fundamental for our understanding of embryo development and adult life in different environments, and central to the diagnosis and treatment of diseases such as stroke, cardiovascular disease, and cancer. This research will contribute to our basic knowledge of these processes, provide invaluable information about the specific genes and proteins involved, and provide direct information about the therapeutic potential of specific drugs or inhibitors designed to target this oxygen response in human disease.Read moreRead less
Investigating the molecular function of alpha-Haemoglobin stabilising protein. The research described in this proposal will provide new insights into haemoglobin regulation and redox chemistry in erythrocytes. Deregulation of these processes gives rise to a number of debilitating diseases, including varieties of anaemia and thalassaemia-in Australia it is estimated that 3% of the population could be carriers of b-thalassaemia mutations. Given the contribution of free aHb to the pathology of b-th ....Investigating the molecular function of alpha-Haemoglobin stabilising protein. The research described in this proposal will provide new insights into haemoglobin regulation and redox chemistry in erythrocytes. Deregulation of these processes gives rise to a number of debilitating diseases, including varieties of anaemia and thalassaemia-in Australia it is estimated that 3% of the population could be carriers of b-thalassaemia mutations. Given the contribution of free aHb to the pathology of b-thalassaemia, understanding the specific aHb-binding factor, AHSP is a goal of national significance. In the long term, manipulation of AHSP function through gene therapy may have a direct role in the treatment of thalassaemia.Read moreRead less
NMR Of Red Cells: Plasma Membrane Oxidoreductase, And Cation Transport
Funder
National Health and Medical Research Council
Funding Amount
$192,388.00
Summary
An interesting paradox exists with respect to the 'central' function of the red blood cell (RBC): it delivers the main oxidising capacity to the body (O2), but it also carries the chemically opposite functionality in its membrane, namely reducing capacity. The reduction of many oxidised proteins and metabolites in blood plasma is mediated by a plasma-membrane oxido-reductase (PMOR). Ascorbic acid (vitamin C) dramatically accelerates this rate of reduction but its precise molecular role is unknow ....An interesting paradox exists with respect to the 'central' function of the red blood cell (RBC): it delivers the main oxidising capacity to the body (O2), but it also carries the chemically opposite functionality in its membrane, namely reducing capacity. The reduction of many oxidised proteins and metabolites in blood plasma is mediated by a plasma-membrane oxido-reductase (PMOR). Ascorbic acid (vitamin C) dramatically accelerates this rate of reduction but its precise molecular role is unknown; neither is the immediate source of the reducing equivalents (electrons) known. Novel, non-invasive, 13C NMR methods have been developed, and others are planned in this project, to study the rate of reduction of Otest? compounds, including 13C-ferricyanide, and reactions of 13C-ascorbate. This will provide a quantitative understanding of the kinetics of the redox reactions in the intact cell. The transfer of negative charges (electrons) from the cell, in the longer term (minutes) inevitably must be matched by the movement of cations (positive charges). The main cation flux is mediated by Na+, K+-ATPase, but various cation exchange pathways are also involved in the total Oionic economy? of the cell. Of special interest will be the calcium-activated K+ (or Gardos) channel. This Oopens? inappropriately in malaria, sickle cell anaemia, and under blood bank storage conditions, and this is thought to be the basis of some of the pathological events in these conditions. The alkali-metal cation exchange pathway ( Na+-Li+) is more activate in the red cells of many patients with hypertension. So, multiple-quantum NMR methods will be used to monitor membrane transport and binding of cations to characterise the kinetics and regulation of the K+-channel, and the Na+-Li+ exchange reactions. The significance will lie in a basic understanding of, and possible 'diagnostic methods' for the biochemical processes that occur in red blood cells in health and disease.Read moreRead less