Sustaining neuronal communication through bulk endocytosis. Brain activities such as learning and memory rely on the ability of neurons to communicate. This research will improve our understanding of how synaptic vesicles recycle during periods of intense synaptic activity. This is a fundamental process relevant to neuronal communication, insulin release, hormone secretion, and allergic responses in health and disease and therefore has broad significance. This work will enhance Australia's exist ....Sustaining neuronal communication through bulk endocytosis. Brain activities such as learning and memory rely on the ability of neurons to communicate. This research will improve our understanding of how synaptic vesicles recycle during periods of intense synaptic activity. This is a fundamental process relevant to neuronal communication, insulin release, hormone secretion, and allergic responses in health and disease and therefore has broad significance. This work will enhance Australia's existing strength in cell biology and neuroscience and provide high quality training for an undergraduate student and post-doctoral scientist.Read moreRead less
Membrane excitability and cellular calcium regulation in the peripheral nervous system under different (patho)-physiological conditions and in inflammatory disease. Studies of cytokine action on neurons and muscle give new insights into functional responses of the nervous system to systemic inflammation and sepsis. In some countries, sepsis is the third most frequent cause of death following heart attack. Elucidating the pathomechanisms allows to develop therapeutic strategies. Electrophysiology ....Membrane excitability and cellular calcium regulation in the peripheral nervous system under different (patho)-physiological conditions and in inflammatory disease. Studies of cytokine action on neurons and muscle give new insights into functional responses of the nervous system to systemic inflammation and sepsis. In some countries, sepsis is the third most frequent cause of death following heart attack. Elucidating the pathomechanisms allows to develop therapeutic strategies. Electrophysiology, Ca2+ regulation and optical membrane potentiometry allow us to monitor early changes in disease on a (sub)cellular level. Experiments on Ca2+ regulation and ion channel function in muscle with different cholesterol membrane contents will help to understand pathomechanisms in high cholesterol diseases, e.g. obesity, on the membrane level long before cardiovascular effects become prominent.Read moreRead less
Assessing the physiological roles of ubiquitination in regulating neuronal ion channels, receptors and transporters. Significant alterations in the activity neuronal transporters and receptors occur during tissue injury and regeneration as well as in many neurodegenerative disease states. Modulation of the pathways that control these transporters is an emerging therapeutic target, however, the molecular basis of these control mechanisms remain poorly understood. The outcome of this project will ....Assessing the physiological roles of ubiquitination in regulating neuronal ion channels, receptors and transporters. Significant alterations in the activity neuronal transporters and receptors occur during tissue injury and regeneration as well as in many neurodegenerative disease states. Modulation of the pathways that control these transporters is an emerging therapeutic target, however, the molecular basis of these control mechanisms remain poorly understood. The outcome of this project will be a thorough characterisation of a novel regulatory paradigm in neurons that is likely to be crucial for neuronal development and regeneration, and will potentially provide novel therapeutic targets for various neuronal diseases.Read moreRead less
G-protein coupled receptor-mediated calcium signalling in parasympathetic neurons. External chemical stimuli act on specific cell-surface receptors of neurons resulting in an increase in the intracellular calcium ion concentration which acts as a second messenger to alter neuronal excitability. There are, however, many receptors acting through a number of closely related proteins involving complex intracellular signalling pathways which remain poorly understood. This project uses molecular, elec ....G-protein coupled receptor-mediated calcium signalling in parasympathetic neurons. External chemical stimuli act on specific cell-surface receptors of neurons resulting in an increase in the intracellular calcium ion concentration which acts as a second messenger to alter neuronal excitability. There are, however, many receptors acting through a number of closely related proteins involving complex intracellular signalling pathways which remain poorly understood. This project uses molecular, electrical and fluorescence techniques to elucidate the molecular basis for these interactions by identifying the roles individual proteins play in integrating diverse extracellular stimuli and neuronal excitablility in the peripheral nervous system.Read moreRead less
Functional ubiquitination of neuronal voltage-gated sodium channels. Alterations in the electrical properties of excitable cells occur during tissue injury and regeneration as well as many disease states. Preventing or controlling these changes is a key strategic therapeutic aim. It is, however, only through a comprehensive understanding of the molecular mechanisms that regulate cellular excitability that we can identify these therapeutic targets. The major outcome of this project will be a thor ....Functional ubiquitination of neuronal voltage-gated sodium channels. Alterations in the electrical properties of excitable cells occur during tissue injury and regeneration as well as many disease states. Preventing or controlling these changes is a key strategic therapeutic aim. It is, however, only through a comprehensive understanding of the molecular mechanisms that regulate cellular excitability that we can identify these therapeutic targets. The major outcome of this project will be a thorough characterisation of a novel pathway that is potentially crucial in the development, homeostasis and regeneration of the nervous system. Disruption of normal function of this system may underlie the hyperexcitability observed in mannu neurodegenerative conditions.Read moreRead less
Glycerotoxin, a unique tool to investigate the dynamic interactions between N-type Ca2+ channels and the exo-endocytic machinery. Communication between neurons relies on exocytosis, a process in which synaptic vesicles containing a neurotransmitter release their content in the extracellular synaptic cleft. We have recently discovered a unique neurotoxin called glycerotoxin (GLTx), which selectively activates Ca2+ channels (Cav2.2), linked with the exocytic machinery in the Central Nervous System ....Glycerotoxin, a unique tool to investigate the dynamic interactions between N-type Ca2+ channels and the exo-endocytic machinery. Communication between neurons relies on exocytosis, a process in which synaptic vesicles containing a neurotransmitter release their content in the extracellular synaptic cleft. We have recently discovered a unique neurotoxin called glycerotoxin (GLTx), which selectively activates Ca2+ channels (Cav2.2), linked with the exocytic machinery in the Central Nervous System. GLTx provide a new tool to further dissect the role of Cav2.2 in controlling neurotransmitter release. GLTx also greatly facilitates synaptic vesicle recycling, suggesting an unexpected link between Cav2.2 activation and the compensatory endocytic machinery. Our goal is to investigate functional coupling between Cav2.2 and the exo- and endocytic machineries using GLTx.Read moreRead less
Mechanism of glutamate transport from experimental and simulation studies. Glutamate transporters play key roles in shaping the electrical signaling in the brain. Under conditions of stress or after a stroke, glutamate transporter function is impaired, which can lead to excessive levels of glutamate, cell death and impaired brain function. The project will help to decipher the operation of glutamate transporters at a molecular level and provide greater understanding of how glutamate levels are c ....Mechanism of glutamate transport from experimental and simulation studies. Glutamate transporters play key roles in shaping the electrical signaling in the brain. Under conditions of stress or after a stroke, glutamate transporter function is impaired, which can lead to excessive levels of glutamate, cell death and impaired brain function. The project will help to decipher the operation of glutamate transporters at a molecular level and provide greater understanding of how glutamate levels are controlled, which is vital for developing better treatments for neurological disorders such as stroke. The project will also provide research training in experimental/computational molecular biology, which is a rapidly growing field underpinning the biotechnological and pharmaceutical industries. Read moreRead less
Conantokin selectivity for heteromeric N-methyl-D-aspartate (NMDA) receptors. NMDA receptors are ligand gated ion channels formed by heterogeneous population of subunits with distinct pharmacological and biophysical properties. The heterogeneic receptors are differentially expressed during development and play an important role in many physiological and pathological processes. Conantokins are toxins isolated from Conus venoms, which target NMDA receptor subunits with high affinity. The primary g ....Conantokin selectivity for heteromeric N-methyl-D-aspartate (NMDA) receptors. NMDA receptors are ligand gated ion channels formed by heterogeneous population of subunits with distinct pharmacological and biophysical properties. The heterogeneic receptors are differentially expressed during development and play an important role in many physiological and pathological processes. Conantokins are toxins isolated from Conus venoms, which target NMDA receptor subunits with high affinity. The primary goal of this study is to examine the effects of conantokins on the molecular properties of different NMDA receptor subtypes in vivo and in vitro.Read moreRead less
Conductance states of a brain glutamine transporter. Brain transporters are the target for many neuroactive drugs that are used to treat anxiety, depression and other psychotic disorders. Transport processes are also targeted to deliver neurotransmitter precursors to the brain to treat disorders such as Parkinson's disease. In this project we will study a transport process crucial for the function of neurons that release glutamate and GABA (gamma-aminobutyric acid) as neurotransmitters. The stud ....Conductance states of a brain glutamine transporter. Brain transporters are the target for many neuroactive drugs that are used to treat anxiety, depression and other psychotic disorders. Transport processes are also targeted to deliver neurotransmitter precursors to the brain to treat disorders such as Parkinson's disease. In this project we will study a transport process crucial for the function of neurons that release glutamate and GABA (gamma-aminobutyric acid) as neurotransmitters. The study of this transport process will be important for understanding disorders like epilepsy and other disorders affecting neuronal excitability.Read moreRead less