Sec17 (α-SNAP) and an SM-tethering complex regulate the outcome of SNARE zippering in vitro and in vivo
| Autor: | Michael Zick, Alexey J. Merz, Rachael L. Plemel, Matthew L. Schwartz, Cortney G. Angers, Mengtong Duan, Braden T. Lobingier, Daniel P. Nickerson |
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| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
Saccharomyces cerevisiae Proteins QH301-705.5 Science Protein subunit Saccharomyces cerevisiae Vesicular Transport Proteins S. cerevisiae Membrane Fusion General Biochemistry Genetics and Molecular Biology Vps33 03 medical and health sciences Biochemistry and Chemical Biology Lysosome medicine Biology (General) HOPS General Immunology and Microbiology biology Tethering Chemistry General Neuroscience Lipid bilayer fusion General Medicine Cell Biology Intracellular Membranes biology.organism_classification Rab AP-3 Cell biology Soluble N-Ethylmaleimide-Sensitive Factor Attachment Proteins 030104 developmental biology medicine.anatomical_structure lysosome Medicine SNARE Proteins Intracellular Sec1/Munc18 Research Article |
| Zdroj: | eLife eLife, Vol 6 (2017) |
| ISSN: | 2050-084X |
| Popis: | Zippering of SNARE complexes spanning docked membranes is essential for most intracellular fusion events. Here, we explore how SNARE regulators operate on discrete zippering states. The formation of a metastable trans-complex, catalyzed by HOPS and its SM subunit Vps33, is followed by subsequent zippering transitions that increase the probability of fusion. Operating independently of Sec18 (NSF) catalysis, Sec17 (α-SNAP) either inhibits or stimulates SNARE-mediated fusion. If HOPS or Vps33 are absent, Sec17 inhibits fusion at an early stage. Thus, Vps33/HOPS promotes productive SNARE assembly in the presence of otherwise inhibitory Sec17. Once SNAREs are partially zipped, Sec17 promotes fusion in either the presence or absence of HOPS, but with faster kinetics when HOPS is absent, suggesting that ejection of the SM is a rate-limiting step. |
| Databáze: | OpenAIRE |
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