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Updated: May 1, 2026

In Vitro Ubiquitination and Deubiquitination Assays of Nucleosomal Histones
Published on: July 25, 2019
The ubiquitylation machinery of the endoplasmic reticulum
Christian Hirsch1, Robert Gauss, Sabine C Horn
1Max-Delbrück Center for Molecular Medicine, Robert-Rössle-Strasse 10, 13125 Berlin, Germany.
Abstract:
As proteins travel through the endoplasmic reticulum (ER), a quality-control system retains newly synthesized polypeptides and supports their maturation. Only properly folded proteins are released to their designated destinations. Proteins that cannot mature are left to accumulate, impairing the function of the ER. To maintain homeostasis, the protein-quality-control system singles out aberrant polypeptides and delivers them to the cytosol, where they are destroyed by the proteasome. The importance of this pathway is evident from the growing list of pathologies associated with quality-control defects in the ER.
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