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Updated: May 21, 2026

Functional Characterization of RING-Type E3 Ubiquitin Ligases In Vitro and In Planta
Published on: December 5, 2019
RING finger palmitoylation of the endoplasmic reticulum Gp78 E3 ubiquitin ligase
Maria Fairbank1, Kun Huang, Alaa El-Husseini
1University of British Columbia, Department of Cellular and Physiological Sciences, Vancouver, British Columbia, Canada.
Abstract:
Gp78 is an E3 ubiquitin ligase within the endoplasmic reticulum-associated degradation pathway. We show that Flag-tagged gp78 undergoes sulfhydryl cysteine palmitoylation (S-palmitoylation) within the RING finger motif, responsible for its ubiquitin ligase activity. Screening of 19 palmitoyl acyl transferases (PATs) identified five that increased gp78 RING finger palmitoylation. Endoplasmic reticulum (ER)-localized Myc-DHHC6 overexpression promoted the peripheral ER distribution of Flag-gp78 while RING finger mutation and the palmitoylation inhibitor 2-bromopalmitate restricted gp78 to the central ER. Palmitoylation of RING finger cysteines therefore regulates gp78 distribution to the peripheral ER.
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