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Updated: Jul 2, 2025

Ubiquitin Chain Analysis by Parallel Reaction Monitoring
Published on: June 17, 2020
Sequential release of interacting proteins and Ub-modifying enzymes by disulfide heterotypic ubiquitin reagents
Hongyi Cai1, Xiangwei Wu2, Junxiong Mao1
1Institute of Translational Medicine, National Center for Translational Medicine (Shanghai), Shanghai Jiao Tong University, Shanghai 200240, China; Tsinghua-Peking Joint Center for Life Sciences, MOE Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Department of Chemistry, Tsinghua University, Beijing 100084, China.
Abstract:
Heterotypic ubiquitin (Ub) chains have emerged as fundamental components in a wide range of cellular processes. The integrative identification of Ub-interacting proteins (readers) and Ub-modifying enzymes (writers and erasers) that selectively recognize and regulate heterotypic ubiquitination may provide crucial insights into these processes. In this study, we employed the bifunctional molecule-assisted (CAET) strategy to develop a type of disulfide bond-activated heterotypic Ub reagents, which allowed to enrich heterotypic Ub-interacting proteins and modifying enzymes simultaneously. The sequential release of readers which are non-covalently bound and writers or erasers which are covalently conjugated by using urea and reductant, respectively, combined with label-free quantitative (LFQ) MS indicated that these heterotypic Ub reagents would facilitate future investigations into functional roles played by heterotypic Ub chains.
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