近日，武汉大学陈素明团队研究了蛋白质甲基丙烯酸基化的化学选择性标记。这一研究成果于2025年11月11日发表在《美国化学会志》上。

蛋白质赖氨酸甲基丙烯酰化（Kmea）是一种新近发现的翻译后修饰，其生物学功能仍不明确。迄今为止，尚未有针对Kmea修饰的化学标记方法，这严重阻碍了甲基丙烯酰化蛋白的发现与功能研究。

研究组开发了一种光催化硫杂迈克尔反应体系，实现了对蛋白甲基丙烯酰化的化学选择性标记。通过利用空间位阻效应与生成的碳中心自由基稳定性的双重作用，有效避免了结构异构体巴豆酰化的反应干扰。基于该反应，设计并合成了多功能水溶性苯硫醇叠氮探针azDSH，并建立了Kmea蛋白的特异性标记、富集与鉴定工作流程。

对组蛋白及核蛋白提取物、全细胞裂解液的蛋白质组学鉴定发现，除组蛋白外，还存在HMGB1、TdIF2、UHRF1、HNRPD、BRWD1、TAF1、TACC1和SETD3等多个新的Kmea修饰蛋白及位点，为表观遗传调控研究提供了新靶点。该研究为生物系统中蛋白甲基丙烯酰化修饰的分析提供了有效方法。

附：英文原文

Title: Chemoselective Tagging of Protein Methacrylation

Author: Ming Gao, Qiongqiong Wan, Shibo Zhou, Pengfei Wu, Wenjing Nie, Suming Chen

Issue&Volume: November 11, 2025

Abstract: Protein lysine methacrylation (Kmea) is a recently identified post-translational modification whose biofunction remains poorly understood. Until now, there has been no chemical labeling method for Kmea modification, which has severely hindered the discovery and functional studies of methacrylated proteins. Here, we developed a photocatalytic thia-Michael reaction system for the chemoselective labeling of protein methacrylation. By exploiting the dual effect of steric hindrance and the stability of the generated C-center radical, the reaction interference of the structural isomer crotonylation can be efficiently avoided. Based on this reaction, a multifunctional water-soluble benzenethiol-azide probe azDSH was designed and synthesized, and a workflow for the specific labeling, enrichment, and identification of Kmea proteins was developed. Proteomic identification of histone and nuclear protein extracts and whole-cell lysate revealed a number of novel Kmea proteins and modification sites besides histones, such as HMGB1, TdIF2, UHRF1, HNRPD, BRWD1, TAF1, TACC1, and SETD3, providing new targets for the study of epigenetic regulation. This study provides an effective method for the analysis of protein methacrylation modifications in biological systems.

DOI: 10.1021/jacs.5c13826

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.5c13826