Synaptotagmin oligomers are necessary and can be sufficient to form a Ca2+ -sensitive fusion clamp.
FEBS Lett
; 593(2): 154-162, 2019 01.
Article
en En
| MEDLINE
| ID: mdl-30570144
ABSTRACT
The buttressed-ring hypothesis, supported by recent cryo-electron tomography analysis of docked synaptic-like vesicles in neuroendocrine cells, postulates that prefusion SNAREpins are stabilized and organized by Synaptotagmin (Syt) ring-like oligomers. Here, we use a reconstituted single-vesicle fusion analysis to test the prediction that destabilizing the Syt1 oligomers destabilizes the clamp and results in spontaneous fusion in the absence of Ca2+ . Vesicles in which Syt oligomerization is compromised by a ring-destabilizing mutation dock and diffuse freely on the bilayer until they fuse spontaneously, similar to vesicles containing only v-SNAREs. In contrast, vesicles containing wild-type Syt are immobile as soon as they attach to the bilayer and remain frozen in place, up to at least 1 h until fusion is triggered by Ca2+ .
Palabras clave
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Vesículas Sinápticas
/
Calcio
/
Sinaptotagmina I
/
Proteínas SNARE
Tipo de estudio:
Diagnostic_studies
/
Prognostic_studies
Límite:
Animals
Idioma:
En
Revista:
FEBS Lett
Año:
2019
Tipo del documento:
Article
País de afiliación:
Estados Unidos