| Autor: |
Jiajie Diao, Patricia Grob, Daniel J Cipriano, Minjoung Kyoung, Yunxiang Zhang, Sachi Shah, Amie Nguyen, Mark Padolina, Ankita Srivastava, Marija Vrljic, Ankita Shah, Eva Nogales, Steven Chu, Axel T Brunger |
| Jazyk: |
angličtina |
| Rok vydání: |
2012 |
| Předmět: |
|
| Zdroj: |
eLife, Vol 1 (2012) |
| Druh dokumentu: |
article |
| ISSN: |
2050-084X |
| DOI: |
10.7554/eLife.00109 |
| Popis: |
The molecular underpinnings of synaptic vesicle fusion for fast neurotransmitter release are still unclear. Here, we used a single vesicle–vesicle system with reconstituted SNARE and synaptotagmin-1 proteoliposomes to decipher the temporal sequence of membrane states upon Ca2+-injection at 250–500 μM on a 100-ms timescale. Furthermore, detailed membrane morphologies were imaged with cryo-electron microscopy before and after Ca2+-injection. We discovered a heterogeneous network of immediate and delayed fusion pathways. Remarkably, all instances of Ca2+-triggered immediate fusion started from a membrane–membrane point-contact and proceeded to complete fusion without discernible hemifusion intermediates. In contrast, pathways that involved a stable hemifusion diaphragm only resulted in fusion after many seconds, if at all. When complexin was included, the Ca2+-triggered fusion network shifted towards the immediate pathway, effectively synchronizing fusion, especially at lower Ca2+-concentration. Synaptic proteins may have evolved to select this immediate pathway out of a heterogeneous network of possible membrane fusion pathways. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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