Synaptic vesicles fuse with the plasma membrane in response to Ca(2+) influx, thereby releasing neurotransmitters into the synaptic cleft. The protein machinery that mediates this process, consisting of soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) and regulatory proteins, is well known, but the mechanisms by which these proteins prime synaptic membranes for fusion are debated. In this study, we applied large-scale, automated cryo-electron tomography to image an in vitro system that reconstitutes synaptic fusion. Our findings suggest that upon docking and priming of vesicles for fast Ca(2)(+)-triggered fusion, SNARE proteins act in concert with regulatory proteins to induce a local protrusion in the plasma membrane, directed towards the primed vesicle. The SNAREs and regulatory proteins thereby stabilize the membrane in a high-energy state from which the activation energy for fusion is profoundly reduced, allowing synchronous and instantaneous fusion upon release of the complexin clamp.
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http://dx.doi.org/10.1002/embr.201337807 | DOI Listing |
Cell Rep
January 2025
State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu, China. Electronic address:
Sterols target sterol-sensing domain (SSD) proteins to lower cholesterol and circulating and hepatic triglyceride levels, but the mechanism remains unclear. In this study, we identify acyl-coenzyme A (CoA) synthetase long-chain family member 1 (ACSL1) as a direct target of ergosterol (ES). The C-terminal domain of ACSL1 undergoes conformational changes from closed to open, and ES may target the drug-binding pocket in the acetyl-CoA synthetase-like domain 1 (ASLD1) of ACSL1 to stabilize the closed conformation and maintain its activity.
View Article and Find Full Text PDFCell Mol Life Sci
January 2025
Department of Anesthesiology, Shenzhen Children's Hospital, Yitian Road 7019, Shenzhen, 518000, China.
Hair follicle (HF) development and pigmentation are complex processes governed by various signaling pathways, such as TGF-β and FGF signaling pathways. Nestin + (neural crest like) stem cells are also expressed in HF stem cells, particularly in the bulge and dermal papilla region. However, the specific role and differentiation potential of these Nestin-positive cells within the HF remain unclear, especially regarding their contribution to melanocyte formation and hair pigmentation.
View Article and Find Full Text PDFXi Bao Yu Fen Zi Mian Yi Xue Za Zhi
January 2025
Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming 650500, China. *Corresponding authors, E-mail:
The innate immune response is the first line of defense for the host against viral infections. Targeted degradation of pathogenic microorganisms through autophagy, in conjunction with pattern recognition receptors synergistically inducing the production of interferon (IFN), constitutes an important pathway for the body to resist viral infections. Rubicon, a Run domain Beclin 1-interacting and cysteine-rich domain protein, has an inhibitory effect on autophagy and IFN production.
View Article and Find Full Text PDFXi Bao Yu Fen Zi Mian Yi Xue Za Zhi
January 2025
Hematologic Disease Center, First Affiliated Hospital of Xinjiang Medical University, Xinjiang Uygur Autonomous Region Research Institute of Hematology, Xinjiang Medical University, Urumqi, Xinjiang Uygur Autonomous Region, Wulumuqi 830011, China. *Corresponding author, E-mail:
Objective This study investigated the regulatory effect of high mobility group protein B1 (HMGB1) in the peripheral blood of patients with primary immune thrombocytopenia (ITP) on myeloid dendritic cells (mDC) and Th17/regulatory T cells (Treg) balance. Methods The study enrolled 30 newly diagnosed ITP patients and 30 healthy controls.Flow cytometry was used to measure the proportion of mDC, Th17, and Treg cells in the peripheral blood of ITP patients and healthy controls.
View Article and Find Full Text PDFJ Transl Med
January 2025
Division of Spine, Department of Orthopedics, Tongji Hospital affiliated to Tongji University, Tongji University School of Medicine, Shanghai, 200065, China.
Background: Ferroptosis and immune responses are critical pathological events in spinal cord injury (SCI), whereas relative molecular and cellular mechanisms remain unclear.
Methods: Micro-array datasets (GSE45006, GSE69334), RNA sequencing (RNA-seq) dataset (GSE151371), spatial transcriptome datasets (GSE214349, GSE184369), and single cell RNA sequencing (scRNA-seq) datasets (GSE162610, GSE226286) were available from the Gene Expression Omnibus (GEO) database. Through weighted gene co-expression network analysis and differential expression analysis in GSE45006, we identified differentially expressed time- and immune-related genes (DETIRGs) associated with chronic SCI and differentially expressed ferroptosis- and immune-related genes (DEFIRGs), which were validated in GSE151371.
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