Visualization of ER-to-Golgi transport in living cells reveals a sequential mode of action for COPII and COPI.

Department of Cell Biology, University of Geneva Sciences III, Switzerland.
Cell (Impact Factor: 33.12). 10/1997; 90(6):1137-48. DOI: 10.1016/S0092-8674(00)80379-7
Source: PubMed

ABSTRACT Exocytic transport from the endoplasmic reticulum (ER) to the Golgi complex has been visualized in living cells using a chimera of the temperature-sensitive glycoprotein of vesicular stomatitis virus and green fluorescent protein (ts-G-GFP[ct]). Upon shifting to permissive temperature, ts-G-GFP(ct) concentrates into COPII-positive structures close to the ER, which then build up to form an intermediate compartment or transport complex, containing ERGIC-53 and the KDEL receptor, where COPII is replaced by COPI. These structures appear heterogenous and move in a microtubule-dependent manner toward the Golgi complex. Our results suggest a sequential mode of COPII and COPI action and indicate that the transport complexes are ER-to-Golgi transport intermediates from which COPI may be involved in recycling material to the ER.

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Available from: Suzie J Scales, Apr 27, 2015
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