Download MendeleyStructural and Functional Analysis of the CAPS SNARE-Binding Domain Required for SNARE Complex Formation and Exocytosis.
Zhou, H., Wei, Z., Wang, S., Yao, D., Zhang, R., Ma, C.(2019) Cell Rep 26: 3347-3359.e6
- PubMed: 30893606
- DOI: https://doi.org/10.1016/j.celrep.2019.02.064
- Primary Citation of Related Structures:
6A68 - PubMed Abstract:
Exocytosis of synaptic vesicles and dense-core vesicles requires both the Munc13 and CAPS (Ca 2+ -dependent activator proteins for secretion) proteins. CAPS contains a soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE)-binding region (called the DAMH domain), which has been found to be essential for SNARE-mediated exocytosis. Here we report a crystal structure of the CAPS-1 DAMH domain at 2.9-Å resolution and reveal a dual role of CAPS-1 in SNARE complex formation. CAPS-1 plays an inhibitory role dependent on binding of the DAMH domain to the MUN domain of Munc13-1, which hinders the ability of Munc13 to catalyze opening of syntaxin-1, inhibiting SNARE complex formation, and a chaperone role dependent on interaction of the DAMH domain with the syntaxin-1/SNAP-25 complex, which stabilizes the open conformation of Syx1, facilitating SNARE complex formation. Our results suggest that CAPS-1 facilitates SNARE complex formation via the DAMH domain in a manner dependent on sequential and cooperative interaction with Munc13-1 and SNARE proteins.
Organizational Affiliation:
Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, 430074 Wuhan, China.
