RT Journal Article
SR Electronic
T1 Uncoating of COPII from ER exit site membranes precedes cargo accumulation and membrane fission
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 727107
DO 10.1101/727107
A1 Olga Shomron
A1 Inbar Nevo-Yassaf
A1 Tamar Aviad
A1 Yakey Yaffe
A1 Eitan Erez Zahavi
A1 Anna Dukhovny
A1 Eran Perlson
A1 Ilya Brodsky
A1 Adva Yeheskel
A1 Metsada Pasmanik-Chor
A1 Anna Mironov
A1 Galina V. Beznoussenko
A1 Alexander A. Mironov
A1 Ella H. Sklan
A1 George H. Patterson
A1 Yoji Yonemura
A1 Christoph Kaether
A1 Koret Hirschberg
YR 2019
UL http://biorxiv.org/content/early/2019/08/06/727107.abstract
AB COPII and COPI are considered to be analogous sets of vesicle coat protein heterocomplexes. Coupled to cargo selection, they mediate the formation of membrane vesicles translocating in opposite directions to differ rent destinations within the secretory pathway. Here, live cell and electron microscopy provided evidence for a different localization and mode of function of the COPII coat during protein export from the endoplasmic reticulum (ER). Pharmaceutical and genetic perturbations of ER-Golgi transport were used to demonstrate that COPII is recruited to membranes defining the boundary of ER-ER Exit Sites (ERES) where it facilitates selective cargo concentration. Uncoating of COPII membranes precedes cargo accumulation and fission of Golgi-bound carriers. Moreover, we report what may be direct transfer of cargo to the Golgi apparatus from Golgi-associated BFA sensitive ERESs. Finally, in ldlF cells the stably expressed functional ε-COPI-EYFP labeled both ERESs and anterograde carriers. These findings change our understanding of the role of coat proteins in ER to Golgi transport.