Involvement of cell coupling in vascular function: Development of a computational model. Gap junctions are intercellular channels which enable the production of coordinated responses in multicellular tissues and organs. Blood vessels are comprised of endothelial cells surrounded by smooth muscle cells and gap junctions exist within and between these layers. The present proposal will determine the fundamental role of gap junctions in regulating blood flow and blood pressure. Our data will enable ....Involvement of cell coupling in vascular function: Development of a computational model. Gap junctions are intercellular channels which enable the production of coordinated responses in multicellular tissues and organs. Blood vessels are comprised of endothelial cells surrounded by smooth muscle cells and gap junctions exist within and between these layers. The present proposal will determine the fundamental role of gap junctions in regulating blood flow and blood pressure. Our data will enable us to develop a computational model of the vascular wall and so predict how changes in electrical properties, as occur during pressure changes, can influence blood flow. Since ageing is accompanied by an increase in blood pressure, our results will contribute to a better understanding of blood flow regulation in our ageing population.Read moreRead less
Suction pipette measurements of mammalian rod photoreceptor recovery following intense bleaching exposures. The aim of this project is to discover the events and processes that prevent retinal photoreceptors from recovering instantaneously following the cessation of exposure to extremely bright illumination. Recordings will be made from single rod photoreceptors cells isolated from the mammalian retina. The work will uncover the relative roles of the 'photoproducts' created when rhodopsin abso ....Suction pipette measurements of mammalian rod photoreceptor recovery following intense bleaching exposures. The aim of this project is to discover the events and processes that prevent retinal photoreceptors from recovering instantaneously following the cessation of exposure to extremely bright illumination. Recordings will be made from single rod photoreceptors cells isolated from the mammalian retina. The work will uncover the relative roles of the 'photoproducts' created when rhodopsin absorbs light: e.g. intermediates such as metarhodopsin and opsin. The molecular knowledge obtained will help us to understand why it is that the visual system recovers so slowly after the eye has experienced very intense light.Read moreRead less
The first stage of vision: transduction and adaptation in retinal photoreceptors. The project aims to provide a detailed understanding of the molecular steps involved in the first stage of vision - the conversion of light into a neural signal in the rod and cone photoreceptors of the retina. The significance of this is that it will explain the initial events that enable us to see, and will help explain the deficits that occur when the process fails. The outcome will be a comprehensive understand ....The first stage of vision: transduction and adaptation in retinal photoreceptors. The project aims to provide a detailed understanding of the molecular steps involved in the first stage of vision - the conversion of light into a neural signal in the rod and cone photoreceptors of the retina. The significance of this is that it will explain the initial events that enable us to see, and will help explain the deficits that occur when the process fails. The outcome will be a comprehensive understanding of how our photoreceptors respond with extreme sensitivity, yet great rapidity, and over an enormous range of light intensities, thus endowing us with our remarkable sense of vision.Read moreRead less
Linkage Infrastructure, Equipment And Facilities - Grant ID: LE0882701
Funder
Australian Research Council
Funding Amount
$300,000.00
Summary
Establishment of a confocal/multiphoton microscope for imaging of living systems. This facility will allow us to study the dynamic changes in living systems, from the smallest unicellular organisms in the ocean through to the sophisticated neural networks of the living brain. Not only will this imaging facility allow us to understand how living systems work, we will also be able to explore the dynamic changes that underlie human disease and injury.
ION CHANNELS FORMED BY SMALL PROTEINS FROM VIRUSES. Movements of ions across cell membranes through protein ion channels are essential for normal cell function. We have found that some small proteins from viruses can form ion channels. Studying these simple channels should give us clues about the function of more complex channels, such as those in the brain, as well as giving us information about the viruses themselves. We will test whether a small protein from Ross River virus forms ion channel ....ION CHANNELS FORMED BY SMALL PROTEINS FROM VIRUSES. Movements of ions across cell membranes through protein ion channels are essential for normal cell function. We have found that some small proteins from viruses can form ion channels. Studying these simple channels should give us clues about the function of more complex channels, such as those in the brain, as well as giving us information about the viruses themselves. We will test whether a small protein from Ross River virus forms ion channels and will also test the effects of selected mutations in proteins from influenza and AIDS viruses that we have shown previously to form ion channels.Read moreRead less
Linkage Infrastructure, Equipment And Facilities - Grant ID: LE0989408
Funder
Australian Research Council
Funding Amount
$150,000.00
Summary
A multiple-ion membrane inlet mass spectrometer. There is a compelling need for a modern isotope-ratio mass spectrometer to facilitate a range of innovative studies of chemical and biochemical processes. Mass spectrometers operated with a thin permeable membrane over a vacuum inlet allow small gas molecules to be continuously monitored inside specific gas or liquid phase sample chambers. The proposed instrumentation will enable simultaneous and highly sensitive measurement of 10 different isot ....A multiple-ion membrane inlet mass spectrometer. There is a compelling need for a modern isotope-ratio mass spectrometer to facilitate a range of innovative studies of chemical and biochemical processes. Mass spectrometers operated with a thin permeable membrane over a vacuum inlet allow small gas molecules to be continuously monitored inside specific gas or liquid phase sample chambers. The proposed instrumentation will enable simultaneous and highly sensitive measurement of 10 different isotopic species and the capability for detection of hydrogen. This equipment will provide the many researchers and students with opportunities to determine isotopic signatures of isolated chemical reactions through to complex biochemical systems of whole living cells.Read moreRead less
Disorder as a novel determinant of photosynthetic structure and function: an experimental study. Australia enjoys a world reputation in photosynthesis research, typified by hosting the 2001 International Photosynthesis Congress. It also has a claim to fame for theoretical work in non-equilibrium thermodynamics concerning production of disorder or entropy, yielding new insights into planetary climates. This experimental project investigates the novel relation between entropy/entropy production ....Disorder as a novel determinant of photosynthetic structure and function: an experimental study. Australia enjoys a world reputation in photosynthesis research, typified by hosting the 2001 International Photosynthesis Congress. It also has a claim to fame for theoretical work in non-equilibrium thermodynamics concerning production of disorder or entropy, yielding new insights into planetary climates. This experimental project investigates the novel relation between entropy/entropy production and the structure/function of the solar powerhouse of plants (chloroplasts), and addresses fundamental questions at the interface of biology and physics. The research explores chloroplasts as a manifestation of the all-pervading Second Law of Thermodynamics, advancing Australia's contribution to basic science and helping to train researchers.Read moreRead less
Using the fractionation of hydrogen and carbon isotopes to analyse the mechanisms of the primary processes of photosynthesis. The primary processes of CO2 fixation and reduction in photosynthesis leave their signatures in the isotopic composition of organic matter. Although these signatures are used widely in geochemistry, biology and climatology to infer the dynamics and history of the biosphere, the information they provide about the mechanisms of the processes that produce them has not been e ....Using the fractionation of hydrogen and carbon isotopes to analyse the mechanisms of the primary processes of photosynthesis. The primary processes of CO2 fixation and reduction in photosynthesis leave their signatures in the isotopic composition of organic matter. Although these signatures are used widely in geochemistry, biology and climatology to infer the dynamics and history of the biosphere, the information they provide about the mechanisms of the processes that produce them has not been exploited fully. We propose to map the underlying biochemistry responsible for fractionation of hydrogen isotopes, to assess its ability to indicate the water relations of plants, and to use carbon-isotope discrimination to probe the catalytic chemistry of the CO2-fixing enzyme, Rubisco.Read moreRead less
Controlling the rate of transcription and translation of Rubisco transgenes effectively in higher-plant plastids. Genetic transformation of the circular genome of the plastids provides a containable means for modifying plant growth by manipulating photosynthesis. Although the transformation mechanism is precise, predicting the level of foreign gene expression is difficult because the amounts of messenger RNA and protein produced by foreign genes in plastids varies widely, even when the protein a ....Controlling the rate of transcription and translation of Rubisco transgenes effectively in higher-plant plastids. Genetic transformation of the circular genome of the plastids provides a containable means for modifying plant growth by manipulating photosynthesis. Although the transformation mechanism is precise, predicting the level of foreign gene expression is difficult because the amounts of messenger RNA and protein produced by foreign genes in plastids varies widely, even when the protein assembles without difficulty. This project will devise strategies for controlling this variability that will facilitate attempts to exploit plastid transformation for transplanting better versions of the photosynthetic CO2-fixing enzyme, Rubisco, into plants to improve their growth efficiency in terms of water, fertiliser and light use.Read moreRead less
Molecular analysis of photosynthetically-linked, active CO2 uptake and CO2 signal transduction by cyanobacteria (blue-green algae). Cyanobacteria (blue-green algae) have evolved a very efficient means of capturing and concentrating CO2 for photosynthetic fixation into sugars, the basic building blocks for cell growth. This process is dependent on the operation of several unique, active uptake systems for CO2 and HCO3-, with their genetic expression regulated by CO2 supply. This proposal will cap ....Molecular analysis of photosynthetically-linked, active CO2 uptake and CO2 signal transduction by cyanobacteria (blue-green algae). Cyanobacteria (blue-green algae) have evolved a very efficient means of capturing and concentrating CO2 for photosynthetic fixation into sugars, the basic building blocks for cell growth. This process is dependent on the operation of several unique, active uptake systems for CO2 and HCO3-, with their genetic expression regulated by CO2 supply. This proposal will capitalize on our progress in describing the functional genetics of this process and aims to elucidate the mechanism of active CO2 uptake and the way that cells sense the ambient CO2 concentration. The information gained is likely to be useful for designing improved crops.Read moreRead less