Deciphering The Molecular Steps Leading To The Potentiation Of Neuronal Exocytosis By Arachidonic Acid
Funder
National Health and Medical Research Council
Funding Amount
$273,000.00
Summary
Release of hormones and neurotransmitters relies on a process called exocytosis which involves SNARE proteins: syntaxin1A and SNAP-25 on the target plasma membrane and VAMP on the vesicular membrane. Availability of the t-SNARE on the plasma membrane is believed to play a major role in controlling the amount of exocytosis. Syntaxin1A bound to Munc18 constitute an 'unproductive-reserve' pool of closed Syntaxin that cannot interact with SNAP-25. Intracellular messengers capable of releasing Syntax ....Release of hormones and neurotransmitters relies on a process called exocytosis which involves SNARE proteins: syntaxin1A and SNAP-25 on the target plasma membrane and VAMP on the vesicular membrane. Availability of the t-SNARE on the plasma membrane is believed to play a major role in controlling the amount of exocytosis. Syntaxin1A bound to Munc18 constitute an 'unproductive-reserve' pool of closed Syntaxin that cannot interact with SNAP-25. Intracellular messengers capable of releasing Syntaxin1A from Munc18 thereby making it available to interact with SNAP-25, are foreseen to play a major role in potentiating exocytosis - a process with ramification for memory and learning. We have identified arachidonic acid, a lipidic messenger which fullfil this role. For the first time we are in a position to manipulate at the molecular level different pools of SNARE proteins with direct implications for our understanding of the mechanism of secretion. Very few models are currently available to understand how learning and memory occur in the brain. Our research points to a new direction: the amount of 'active' and 'unproductive-reserve' pools of SNARE proteins present on the plasma membrane of neurosecretory cells are in dynamic equilibrium and arachidonic acid, a second messenger capable of trans-synaptic action, can modify this equilibrium resulting in an increase of the amount of 'active' SNARE thereby potentiating the amount of transmitter-hormone released by exocytosis. Importantly, this research lays the basis for a dynamic view of the secretory mechanism with important implications for treatment of diseases such as diabetes and neurodegenerative diseases. Our hope is that by understanding at the molecular level how secretory cells regulate the amount of their secretion, we will be in a position to modify these parameters in order to counteract illnesses of the nervous system.Read moreRead less
Linkage Infrastructure, Equipment And Facilities - Grant ID: LE170100096
Funder
Australian Research Council
Funding Amount
$325,000.00
Summary
High resolution atomic force microscopy facility for bionanotechnology. This project aims to establish a collaborative high resolution atomic force microscopy facility. Nanoscale surface structure and the complex structure/mechanical-functional relationships underpin many biological processes, and understanding cell systems at the molecular level is expected to lead to scientific knowledge and therapeutic and other biotechnological applications. Expected outcomes include innovations in advanced ....High resolution atomic force microscopy facility for bionanotechnology. This project aims to establish a collaborative high resolution atomic force microscopy facility. Nanoscale surface structure and the complex structure/mechanical-functional relationships underpin many biological processes, and understanding cell systems at the molecular level is expected to lead to scientific knowledge and therapeutic and other biotechnological applications. Expected outcomes include innovations in advanced manufacturing in the pharmaceutical and medical devices industries, underpinning economic returns from new industries.Read moreRead less
Linkage Infrastructure, Equipment And Facilities - Grant ID: LE170100206
Funder
Australian Research Council
Funding Amount
$550,000.00
Summary
Lattice light sheet microscopy for imaging biology in real space and time. This project aims to establish a Lattice Light-Sheet Microscope (LLSM) Facility, to provide the dedicated computing infrastructure needed for terabyte-scale image acquisition and handling. Lattice light sheet microscopy allows four-dimensional imaging of live biological specimens from individual molecules to small organisms. The microscope images live specimens without phototoxicity or photobleaching, enabling prolonged i ....Lattice light sheet microscopy for imaging biology in real space and time. This project aims to establish a Lattice Light-Sheet Microscope (LLSM) Facility, to provide the dedicated computing infrastructure needed for terabyte-scale image acquisition and handling. Lattice light sheet microscopy allows four-dimensional imaging of live biological specimens from individual molecules to small organisms. The microscope images live specimens without phototoxicity or photobleaching, enabling prolonged imaging of significant physiological or biophysical events. Expected outcomes include high impact discoveries and publications in fundamental research, rapid solutions for industry-focussed projects and opportunities for collaboration, research and development. The imaging is expected to reveal key scientific insights and showcase biology to the public.Read moreRead less
Molecular insights into bacterial metal ion homeostasis and toxicity. This project aims to measure bacterial cellular metal concentrations, elucidate mechanisms cells use to adapt to changing extracellular metal concentrations, and reveal the molecular targets of metal toxicity. Metal ions are essential to all forms of life, and half of all proteins use metal ions for cellular chemical processes. However, how cells precisely balance sufficient metal ions for essential cellular chemistry without ....Molecular insights into bacterial metal ion homeostasis and toxicity. This project aims to measure bacterial cellular metal concentrations, elucidate mechanisms cells use to adapt to changing extracellular metal concentrations, and reveal the molecular targets of metal toxicity. Metal ions are essential to all forms of life, and half of all proteins use metal ions for cellular chemical processes. However, how cells precisely balance sufficient metal ions for essential cellular chemistry without accumulating a toxic excess (metal homeostasis) is poorly understood. Discovering the roles of metal ions in bacterial cells will be key to defining the chemical biology of living systems and will provide information essential to understanding how microbes adapt to changing environments.Read moreRead less
Linkage Infrastructure, Equipment And Facilities - Grant ID: LE120100224
Funder
Australian Research Council
Funding Amount
$250,000.00
Summary
Multi-mode fluorescence microscope for visualising the dynamics of cellular processes at the single-molecule level. Fluorescence is the emission of light by a substance that has absorbed light of a different wavelength. This fluorescence microscopy facility will allow the visualisation of the dynamic processes that define life at the molecular level. This insight will help us understand cellular function and how it is impaired in various diseases including cancer and neurodegenerative disorders ....Multi-mode fluorescence microscope for visualising the dynamics of cellular processes at the single-molecule level. Fluorescence is the emission of light by a substance that has absorbed light of a different wavelength. This fluorescence microscopy facility will allow the visualisation of the dynamic processes that define life at the molecular level. This insight will help us understand cellular function and how it is impaired in various diseases including cancer and neurodegenerative disorders such as Parkinson’s and Alzheimer’s disease.Read moreRead less
New molecular tools to study the mechanisms of bacterial metal homeostasis. This project aims to provide new insight into how metal ion uptake is regulated. It will precisely measure the cellular concentrations of metal ions, reveal the roles of metal ions in essential cellular processes, and identify the molecular targets of metal toxicity. Metal ions are essential to all forms of life and are used by up to half of all proteins to facilitate cellular chemical processes. The intended outcome of ....New molecular tools to study the mechanisms of bacterial metal homeostasis. This project aims to provide new insight into how metal ion uptake is regulated. It will precisely measure the cellular concentrations of metal ions, reveal the roles of metal ions in essential cellular processes, and identify the molecular targets of metal toxicity. Metal ions are essential to all forms of life and are used by up to half of all proteins to facilitate cellular chemical processes. The intended outcome of the research is to provide new fundamental knowledge of the roles of metal ions in bacterial cells; knowledge that will be key to defining the chemical biology of living systems and will provide information essential to understanding how microbes adapt to changing environments.Read moreRead less
Plasmonic nanoparticles for probing and perturbing the spatial organisation of membrane proteins. Receptors on the surface of cells provide vital functions and represent a large fraction of drug targets. It is believed that the spatial organisation of receptors can effect their function. This project will test this hypothesis by combining nanotechnology with biophysics to watch and manipulate the spatial organisation of receptors.
Tuning Molecular Translocaton by Close-Field Electroporation. This project aims to determine the underlying mechanisms by which DNA and other molecules are able to migrate across the cell membrane in response to highly localised electric fields. It has recently been shown that focusing of electric fields at the cellular level, using an array of small electrodes, results in unexpectedly high cell transfection efficiencies. It has been termed 'close-field electroporation'. Here it is proposed t ....Tuning Molecular Translocaton by Close-Field Electroporation. This project aims to determine the underlying mechanisms by which DNA and other molecules are able to migrate across the cell membrane in response to highly localised electric fields. It has recently been shown that focusing of electric fields at the cellular level, using an array of small electrodes, results in unexpectedly high cell transfection efficiencies. It has been termed 'close-field electroporation'. Here it is proposed to establish the properties of the electric fields around cells and cell membrane interactions with these fields that enable molecular translocation. This fundamental science could have broad implications in the domains of drug delivery, gene therapy and neural stimulation.Read moreRead less
Molecular mechanisms of mechanosensation and shape regulation in cells. This project aims to explore how cells physically sense and respond to the surrounding environment on a molecular level. Physical distortion of erythrocytes doubles their glucose consumption and increases cation membrane flux five-fold. This mechanism involves opening of the mechanosenstive ion channel Piezo1. This project will include a kinetic description of these phenomena, with a goal to establish a predictive mathematic ....Molecular mechanisms of mechanosensation and shape regulation in cells. This project aims to explore how cells physically sense and respond to the surrounding environment on a molecular level. Physical distortion of erythrocytes doubles their glucose consumption and increases cation membrane flux five-fold. This mechanism involves opening of the mechanosenstive ion channel Piezo1. This project will include a kinetic description of these phenomena, with a goal to establish a predictive mathematical model of the regulation of cell-shape and volume. The project will provide an understanding of mechanisms operating when cells and tissues are succumbing to trauma and invasion, and how to control these processes on a molecular level.Read moreRead less
Elucidating the determinants of cation import across the kingdoms of life. The metal ion manganese is essential to all forms of life. This project aims to investigate how this poorly abundant cation is selectively acquired from the chemical complexity of the environment for import into cells by using state-of-the-art biochemical and microbiological techniques. This project expects to define the fundamental basis for how bacterial, archaeal and eukaryotic plastid cation-selective importers can di ....Elucidating the determinants of cation import across the kingdoms of life. The metal ion manganese is essential to all forms of life. This project aims to investigate how this poorly abundant cation is selectively acquired from the chemical complexity of the environment for import into cells by using state-of-the-art biochemical and microbiological techniques. This project expects to define the fundamental basis for how bacterial, archaeal and eukaryotic plastid cation-selective importers can discriminate manganese from chemical similar cations to achieve selective uptake. The expected outcomes of this work will be an understanding of the fundamental basis for selective metal import in biological systems. This should provide benefits for industry through synthetic biological applications of this knowledge. Read moreRead less