A5046252364- Cellular transport and secretion
- Lipid Membrane Structure and Behavior
- Neuroscience and Neuropharmacology Research
- Erythrocyte Function and Pathophysiology
- RNA Research and Splicing
- Advanced Fluorescence Microscopy Techniques
- Photoreceptor and optogenetics research
- Nerve injury and regeneration
- Supramolecular Self-Assembly in Materials
- Cellular Mechanics and Interactions
- Genetics and Neurodevelopmental Disorders
- Pain Mechanisms and Treatments
- Botulinum Toxin and Related Neurological Disorders
- Alzheimer's disease research and treatments
- Cancer-related molecular mechanisms research
- Enzyme Structure and Function
- Monoclonal and Polyclonal Antibodies Research
- Biochemical and Structural Characterization
- Fungal Biology and Applications
- RNA regulation and disease
- Peroxisome Proliferator-Activated Receptors
- Spectroscopy Techniques in Biomedical and Chemical Research
- Ubiquitin and proteasome pathways
- Growth Hormone and Insulin-like Growth Factors
- Lysosomal Storage Disorders Research
Park Centre for Mental Health
2015-2024
The University of Queensland
2015-2024
Children's Medical Research Institute
2023
The University of Sydney
2023
Johns Hopkins University
2023
Nanyang Technological University
2023
Joensuu Science Park
2023
Allen Institute for Brain Science
2022
Protein kinases (PKs) are proteins at the core of cellular signalling and thereby responsible for most physiological processes their regulations. As all intracellular proteins, PKs subjected to Brownian thermal energy that tends homogenise distribution throughout volume cell. To access substrates perform critical functions, PK localisation is therefore tightly regulated in space time, relying upon a range clustering mechanisms. These include post-translational modifications, protein-protein...
Abstract The phospholipid and free fatty acid (FFA) composition of neuronal membranes plays a crucial role in learning memory, but the mechanisms through which activity affects brain’s lipid landscape remain largely unexplored. levels saturated FFAs, particularly myristic (C14:0), strongly increase during stimulation memory acquisition, suggesting involvement phospholipase A1 (PLA1) synaptic plasticity. Here, we show that genetic ablation PLA1 isoform DDHD2 mice dramatically reduces FFA...
Axonal retrograde transport of signalling endosomes from the nerve terminal to soma underpins survival. As each endosome carries a quantal amount activated receptors, we hypothesized that it is frequency reaching determines scale trophic signal. Here show upregulating synaptic activity markedly increased flux plasma membrane-derived (labelled using cholera toxin subunit-B: CTB) in hippocampal neurons cultured microfluidic devices, and live Drosophila larval motor neurons. Electron...
Munc18-1 is a key component of the exocytic machinery that controls neurotransmitter release. heterozygous mutations cause developmental defects and epileptic phenotypes, including infantile encephalopathy (EIEE), suggestive gain pathological function. Here, we used single-molecule analysis, gene-edited cells, neurons to demonstrate EIEE-causing mutants form large polymers coaggregate wild-type in vitro cells. Surprisingly, EIEE also Lewy body–like structures contain α-synuclein (α-Syn). We...
The traditional medicinal mushroom Hericium erinaceus is known for enhancing peripheral nerve regeneration through targeting growth factor (NGF) neurotrophic activity. Here, we purified and identified biologically new active compounds from H. erinaceus, based on their ability to promote neurite outgrowth in hippocampal neurons. N-de phenylethyl isohericerin (NDPIH), an isoindoline compound this mushroom, together with its hydrophobic derivative hericene A, were highly potent promoting...
Single-molecule localization microscopy techniques are emerging as vital tools to unravel the nanoscale world of living cells by understanding spatiotemporal organization protein clusters at nanometer scale. Current analyses define spatial nanoclusters based on detections but neglect important temporal information such cluster lifetime and recurrence in "hotspots" plasma membrane. Spatial indexing is widely used video games detect interactions between moving geometric objects. Here, we use...
Before undergoing neuroexocytosis, secretory granules (SGs) are mobilized and tethered to the cortical actin network by an unknown mechanism. Using SG pull-down assay mass spectrometry, we found that myosin VI was recruited SGs in a Ca2+-dependent manner. Interfering with function PC12 cells reduced density of near plasma membrane without affecting their biogenesis. Myosin knockdown selectively impaired late phase exocytosis, consistent replenishment defect. This exocytic defect rescued...
In neurosecretory cells, secretory vesicles (SVs) undergo Ca(2+)-dependent fusion with the plasma membrane to release neurotransmitters. How SVs cross dense mesh of cortical actin network reach remains unclear. Here we reveal that, in bovine chromaffin embedded a highly synchronized transition towards and Munc18-1-dependent docking response secretagogues. This movement coincides translocation same direction. Both effects are abolished by knockdown or pharmacological inhibition myosin II,...
Propofol is the most commonly used general anesthetic in humans. Our understanding of its mechanism action has focused on capacity to potentiate inhibitory systems brain. However, it unknown whether other neural mechanisms are involved anesthesia. Here, we demonstrate that synaptic release machinery also a target. Using single-particle tracking photoactivation localization microscopy, show clinically relevant concentrations propofol and etomidate restrict syntaxin1A mobility plasma membrane,...
Munc18-1 and syntaxin-1A control SNARE-dependent neuroexocytosis are organized in nanodomains on the plasma membrane of neurons neurosecretory cells. Deciphering intra- intermolecular steps via which they prepare secretory vesicles (SVs) for fusion is key to understanding neuronal hormonal communication. Here, we demonstrate that expression a priming-deficient mutant lacking 17 residues domain 3a hinge-loop (Munc18-1Δ317-333) PC12 cells engineered knockdown Munc18-1/2 markedly prolonged SV...
Abstract Neuronal communication relies on the release of neurotransmitters from various populations synaptic vesicles. Despite displaying vastly different probabilities and mobilities, reserve recycling pool vesicles co-exist within a single cluster suggesting that small biomolecular condensates could regulate their nanoscale distribution. Here, we performed large-scale activity-dependent phosphoproteome analysis hippocampal neurons in vitro identified Tau as highly phosphorylated disordered...
The unique nerve terminal targeting of botulinum neurotoxin type A (BoNT/A) is due to its capacity bind two receptors on the neuronal plasma membrane: polysialoganglioside (PSG) and synaptic vesicle glycoprotein 2 (SV2). Whether how PSGs SV2 may coordinate other proteins for BoNT/A recruitment internalization remains unknown. Here, we demonstrate that targeted endocytosis into vesicles (SVs) requires a tripartite surface nanocluster. Live-cell super-resolution imaging electron microscopy...
Long noncoding RNAs (lncRNAs) represent a multidimensional class of regulatory molecules that are involved in many aspects brain function. Emerging evidence indicates lncRNAs localized to the synapse; however, direct role for their activity this subcellular compartment memory formation has yet be demonstrated. Using lncRNA capture-seq, we identified specific set accumulate synaptic within infralimbic prefrontal cortex adult male C57/Bl6 mice. Among these was splice variant related...
Munc18-interacting proteins (Mints) are multidomain adaptors that regulate neuronal membrane trafficking, signaling, and neurotransmission. Mint1 Mint2 highly expressed in the brain with overlapping roles regulation of synaptic vesicle fusion required for neurotransmitter release by interacting essential protein Munc18-1. Here, we have used AlphaFold2 to identify then validate mechanisms underpin both specific interactions Mint Munc18-1 as well their wider interactome. We found a short...
Munc18-1 plays a dual role in transporting syntaxin-1A (Sx1a) to the plasma membrane and regulating SNARE-mediated fusion. As impairment of either function leads common exocytic defect, assigning specific roles for various domains has proved difficult. Structural analyses predict that loop region domain 3a could catalyse conversion Sx1a from 'closed', fusion-incompetent an 'open', fusion-competent conformation. this occurs at membrane, mutations potentially separate chaperone functions...
Significance Proteins moving freely on the plasma membrane can become transiently trapped in functionally essential clusters. This capability is likely to be influenced by subtle conformational states of protein promoting or preventing such confinement. The downside conventional imaging overexpressed tagged proteins that it precludes selective tracking inherently minor albeit conformer populations. Intracellular expression single-chain nanobodies allowed us track endogenous highly specific...
Abstract Neurotransmitter release relies on the regulated fusion of synaptic vesicles (SVs) that are tightly packed within presynaptic bouton neurons. The mechanism by which SVs clustered at presynapse, while preserving their ability to dynamically recycle support neuronal communication, remains unknown. Synapsin 2a (Syn2a) tetramerization has been suggested as a potential clustering mechanism. Here, we used Dual-pulse sub-diffractional Tracking Internalised Molecules (DsdTIM) simultaneously...
Mutations in Munc18-1, an essential component of the machinery controlling neurotransmission, are linked to development early infantile epileptic encephalopathy (EIEE).In this study, Martin et al. show that one these mutations, C180Y, results a thermolabile protein with strong propensity aggregate.The level Munc18-1C180Y is regulated by K48-linked polyubiquitination and proteasomal degradation.The impaired exocytic function rescued growth at permissive temperature.An imbalance exocytosis...
Activity-dependent bulk endocytosis allows neurons to internalize large portions of the plasma membrane in response stimulation. However, whether this critical type compensatory is unique or also occurs other excitable cells currently unknown. Here we used fluorescent 70 kDa dextran demonstrate that secretagogue-induced bovine chromaffin cells. The relatively size endosomes found model allowed us investigate how neck budding constricts allow efficient recruitment fission machinery. Using...
Growth hormone (GH) acts via JAK2 and LYN to regulate growth, metabolism, neural function. However, the relationship between these tyrosine kinases remains enigmatic. Through an interdisciplinary approach combining cell biology, structural computation, single-particle tracking on live cells, we find overlapping Box1-Box2-binding regions in GH receptor (GHR). Our data implicate direct competition for GHR binding imply divergent signaling profiles. We show that exhibits distinct mobility...
Endocytosis requires a coordinated framework of molecular interactions that ultimately lead to the fission nascent endocytic structures. How cytosolic proteins such as dynamin concentrate at discrete sites are sparsely distributed across plasma membrane remains poorly understood. Two dynamin-1 major splice variants differ by length their C-terminal proline-rich region (short-tail and long-tail). Using sptPALM in PC12 cells, neurons MEF we demonstrate short-tail isoforms ab bb display an...
Alzheimer's disease (AD) is associated with the cleavage of amyloid precursor protein (APP) to produce toxic amyloid-β (Aβ) peptide. Accumulation Aβ, together concomitant inflammatory response, ultimately leads neuronal death and cognitive decline. Despite AD progression being underpinned by both immunological components, therapeutic strategies based on dual targeting these systems remains unexplored. Here, we report that inactivation p110δ isoform phosphoinositide 3-kinase (PI3K) reduces...
Abstract Fyn is a Src kinase that controls critical signalling cascades and has been implicated in learning memory. Postsynaptic enrichment of underpins synaptotoxicity dementias such as Alzheimer’s disease frontotemporal lobar degeneration with Tau pathology (FTLD-Tau). The FLTD P301L mutant associated higher propensity to undergo liquid–liquid phase separation (LLPS) form biomolecular condensates. Expression promotes aberrant trapping nanoclusters within hippocampal dendrites by an unknown...
Following exocytosis, the recapture of plasma membrane-stranded vesicular proteins into recycling synaptic vesicles (SVs) is essential for sustaining neurotransmission. Surface clustering has been proposed to act as a 'pre-assembly' mechanism endocytosis that ensures high-fidelity retrieval SV cargo. Here, we used single-molecule imaging examine nanoclustering synaptotagmin-1 (Syt1) and vesicle protein 2A (SV2A) in hippocampal neurons. Syt1 forms surface nanoclusters through interaction its...