Related Experiment Video
Updated: May 8, 2026

In Vitro Ubiquitination and Deubiquitination Assays of Nucleosomal Histones
Published on: July 25, 2019
Ubiquitin-dependent regulation of COPII coat size and function
Lingyan Jin1, Kanika Bajaj Pahuja, Katherine E Wickliffe
1Department of Molecular and Cell Biology, University of California at Berkeley, California 94720, USA.
None:
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.
Related Concept Videos
Covalently Linked Protein Regulators
These groups modify specific amino acids in a protein.
Regulated Protein Degradation
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
Coat Assembly and GTPases
Coat assembly depends on the local availability of phosphatidylinositol phosphates or PIPs and GTP-binding proteins. Adaptor proteins, which link the coat proteins to the membrane, bind to these PIPs and play a crucial role in controlling...
Regulation of the Unfolded Protein Response
Covalently Linked Protein Regulators
These groups modify specific amino acids in a protein.
Regulated Protein Degradation
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...

