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Biology
Dmitry Shvarev, Jannis Schoppe, Caroline Koenig, Angela Perz, Nadia Fuellbrunn, Stephan Kiontke, Lars Langemeyer, Dovile Januliene, Kilian Schnelle, Daniel Kuemmel, Florian Froehlich, Arne Moeller, Christian Ungermann
Summary: Lysosomes are crucial for cell survival and function, and the HOPS complex plays a key role in lysosomal fusion. In this study, we used cryo-electron microscopy to examine the structure of HOPS and found that its flexibility is limited to the GTPase binding region. The SNARE-binding module is firmly attached to the core, positioning it ideally for membrane fusion.
Article
Biology
Hongki Song, William T. Wickner, Adam Linstedt
Summary: The yeast vacuolar membrane fusion process can be achieved using a synthetic tether instead of the HOPS complex. This suggests that Sec17 and Sec18 play a crucial role in membrane fusion and may have a general role in promoting fusion across different cellular processes.
Article
Multidisciplinary Sciences
Agata Witkowska, Leonard P. Heinz, Helmut Grubmueller, Reinhard Jahn
Summary: Proteins driving membrane fusion must overcome energy barriers to induce intermediate steps where lipid bilayers' integrity is lost. The metastable intermediate preceding hemifusion does not require but is enhanced by divalent cations, characterized by the absence of proteins and local membrane thickening, induced by lipid rearrangements due to dehydration of the membrane surface revealed by simulations.
NATURE COMMUNICATIONS
(2021)
Article
Biology
Hongki Song, Thomas L. Torng, Amy S. Orr, Axel T. Brunger, William T. Wickner
Summary: Membrane fusion requires SNARE proteins to form coiled coils, but Sec17 and Sec18 can promote fusion without the need for completion of the coiled coils. Specific blocks in SNARE proteins can be bypassed by Sec17 and Sec18 to restore fusion.
Article
Microbiology
Yue Chen, Jia Liu, Yani Fan, Meichun Xiang, Seogchan Kang, Dongsheng Wei, Xingzhong Liu
Summary: DdVam7 protein plays a crucial role in D. dactyloides, regulating fungal growth, conidiation, and predatory process by mediating vacuole assembly, providing a basis for studying mechanisms of NTF and ring cell rapid inflation.
MICROBIOLOGY SPECTRUM
(2022)
Article
Biochemistry & Molecular Biology
Min Zhu, Han Xu, Yuting Jiang, Haijia Yu, Yinghui Liu
Summary: Insulin secretion is a signal-triggered process that involves membrane fusion mediated by SNAREs. This study reveals that EGCG efficiently inhibits SNARE-mediated insulin secretory vesicle fusion, making it a potential regulator of SNARE-dependent insulin secretion.
Article
Cell Biology
Amy Orr, William Wickner
Summary: Membrane fusion is driven by the interactions between Sec17, Sec18, and SNARE. Sec17 promotes fusion by binding to SNARE, while Sec18 aids Sec17 in fusion by lowering its affinity. ATP acts as a ligand to activate Sec18 for fusion, but ATP hydrolysis is not required.
MOLECULAR BIOLOGY OF THE CELL
(2022)
Article
Cell Biology
Thomas Torng, William Wickner
Summary: Intracellular membrane fusion requires a combination of specific lipids such as phosphatidylinositol and phosphatidylinositol-3-phosphate for HOPS activation and other lipids like phosphatidylethanolamine, phosphatidic acid, phosphatidylserine, and diacylglycerol for the terminal bilayer rearrangement step of fusion. Different lipid requirements are crucial for activating HOPS for trans-SNARE assembly and for the final fusion process.
MOLECULAR BIOLOGY OF THE CELL
(2021)