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Updated: Sep 24, 2025

In Vitro Analysis of E3 Ubiquitin Ligase Function
Published on: May 14, 2021
Assembly and function of branched ubiquitin chains
SriDurgaDevi Kolla1, Mengchen Ye1, Kevin G Mark1
1Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA.
Abstract:
Post-translational modification with ubiquitin is required for cell division, differentiation, and survival in all eukaryotes. As part of an intricate signaling code, ubiquitin is attached to its targets as single molecules or polymeric chains, with the distinct modifications encoding a wide range of outcomes. After early work focused on homotypic ubiquitin chains, such as the K48-linked polymers that drive proteasomal degradation, recent studies noted abundant conjugates that contained ubiquitin molecules modified on two or more sites. Such branched ubiquitin chains are produced in response to specific signals and they exert functions that are critical for cellular and organismal homeostasis. In this review, we will discuss our rapidly evolving understanding of the assembly and function of branched ubiquitin chains.
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