Year: 2017
Type: article
Abstract: The coat protein complex II (COPII) is essential for the secretion of large cargo, such as the 300 nm precursor fibrils of procollagen I (PC1). Previous work has shown that the CUL3-KLHL12 complex increases the size of COPII vesicles to over 300 nm in diameter and accelerates the secretion of PC1; however, the role of large COPII vesicles as PC1 transport carriers was not unambiguously demonstrated. In this study, using stochastic optical reconstruction microscopy (STORM), correlated light electron microscopy (CLEM), and live cell imaging we report the existence of mobile COPII-coated vesicles that completely encapsulate the cargo PC1 and are physically separated from ER. We have also developed a cell-free COPII vesicle budding reaction that reconstitutes the capture of PC1 into large COPII vesicles. This process requires COPII proteins and the GTPase activity of the COPII subunit SAR1. We conclude from in vivo and in vitro evidence that large COPII vesicles are bona fide carriers of PC1. Summary COPII may play a direct or indirect role in the traffic of large protein complexes such as procollagen. Using high resolution imaging techniques in intact cells and in vitro reconstituted vesicles, Gorur et al. show that COPII coated vesicles carry procollagen1.
Source: The Journal of Cell Biology
Language: English
Subfield: Cell Biology
Domain: Life Sciences
Open Access status: hybrid
Funders: National Science Foundation, Howard Hughes Medical Institute, Gordon and Betty Moore Foundation, University of California Berkeley, Adolph C. and Mary Sprague Miller Institute for Basic Research in Science, University of California Berkeley, National Institutes of Health, National Center for Research Resources, Division of Chemistry, Lawrence Berkeley National Laboratory
Awards: A Zeiss Elyra S1 Structured Illumination Microscope for the Biological Imaging Fa, G2487583129, CAREER: Chemical Imaging through Ultrahigh-Throughput Single-Molecule Spectroscopy and Spectrally-Resolved Superresolution Microscopy, A Zeiss LSM 710 confocal microscope for the Biological Imaging Facility at the U, G4821206068, G8895217444
OpenAlex ID: W2951666921