title: Ubiquitin-dependent regulation of COPII coat size and function.
abstract: Packaging of proteins from the endoplasmic reticulum into COPII vesicles is essential for secretion. In cells, most COPII vesicles are approximately 60-80 nm in diameter, yet some must increase their size to accommodate 300-400 nm procollagen fibres or chylomicrons. Impaired COPII function results in collagen deposition defects, cranio-lenticulo-sutural dysplasia, or chylomicron retention disease, but mechanisms to enlarge COPII coats have remained elusive. Here, we identified the ubiquitin ligase CUL3-KLHL12 as a regulator of COPII coat formation. CUL3-KLHL12 catalyses the monoubiquitylation of the COPII-component SEC31 and drives the assembly of large COPII coats. As a result, ubiquitylation by CUL3-KLHL12 is essential for collagen export, yet less important for the transport of small cargo. We conclude that monoubiquitylation controls the size and function of a vesicle coat.
authors.affiliation: Department of Molecular and Cell Biology, University of California at Berkeley, California 94720, USA.
authors.forename: Lingyan
authors.initials: L
authors.lastname: Jin
authors.forename: Kanika Bajaj
authors.initials: KB
authors.lastname: Pahuja
authors.forename: Katherine E
authors.initials: KE
authors.lastname: Wickliffe
authors.forename: Amita
authors.initials: A
authors.lastname: Gorur
authors.forename: Christine
authors.initials: C
authors.lastname: Baumgärtel
authors.forename: Randy
authors.initials: R
authors.lastname: Schekman
authors.forename: Michael
authors.initials: M
authors.lastname: Rape
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D022181:COP-Coated Vesicles / Q000737:chemistry* / Q000378:metabolism*; D002460:Cell Line; D048430:Cell Shape; D003094:Collagen / Q000378:metabolism; D044842:Cullin Proteins / Q000235:genetics / Q000378:metabolism; D053595:Embryonic Stem Cells / Q000166:cytology / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D008840:Microfilament Proteins / Q000235:genetics / Q000378:metabolism; D021381:Protein Transport; D025801:Ubiquitin / Q000378:metabolism*; D054875:Ubiquitination; D033921:Vesicular Transport Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C503645:CUL3 protein, human; D044842:Cullin Proteins; C493279:KLHL12 protein, human; D008840:Microfilament Proteins; D025801:Ubiquitin; D033921:Vesicular Transport Proteins; D003094:Collagen