| First Author | Vardar G | Year | 2021 |
| Journal | Elife | Volume | 10 |
| PubMed ID | 34427183 | Mgi Jnum | J:311117 |
| Mgi Id | MGI:6765771 | Doi | 10.7554/eLife.69498 |
| Citation | Vardar G, et al. (2021) Reexamination of N-terminal domains of syntaxin-1 in vesicle fusion from central murine synapses. Elife 10:e69498 |
| abstractText | Syntaxin-1 (STX1) and Munc18-1 are two requisite components of synaptic vesicular release machinery, so much so synaptic transmission cannot proceed in their absence. They form a tight complex through two major binding modes: through STX1's N-peptide and through STX1's closed conformation driven by its Habc- domain. However, physiological roles of these two reportedly different binding modes in synapses are still controversial. Here we characterized the roles of STX1's N-peptide, Habc-domain, and open conformation with and without N-peptide deletion using our STX1-null mouse model system and exogenous reintroduction of STX1A mutants. We show, on the contrary to the general view, that the Habc-domain is absolutely required and N-peptide is dispensable for synaptic transmission. However, STX1A's N-peptide plays a regulatory role, particularly in the Ca(2+)-sensitivity and the short-term plasticity of vesicular release, whereas STX1's open conformation governs the vesicle fusogenicity. Strikingly, we also show neurotransmitter release still proceeds when the two interaction modes between STX1A and Munc18-1 are presumably intervened, necessitating a refinement of the conceptualization of STX1A-Munc18-1 interaction. |
