Center for RNA Research, Institute for Basic Science, Seoul 08826, Korea.
School of Biological Sciences, Seoul National University, Seoul 08826, Korea.
Anal Chem. 2020 Apr 7;92(7):4926-4934. doi: 10.1021/acs.analchem.9b05035. Epub 2020 Mar 30.
Protein expression levels are regulated through both translation and degradation mechanisms. Levels of degradation intermediates, that is, partially degraded proteins, cannot be distinguished from those of intact proteins by global proteomics analysis, which quantify total protein abundance levels. This study aimed to develop a tool for assessing the aspects of degradation regulation via proteolytic processing through a new multiplexed N-terminomics method involving selective isobaric labeling of protein N-termini and immunoaffinity capture of the labeled N-terminal peptides. Our method allows for not only identification of proteolytic cleavage sites, but also highly multiplexed quantification of proteolytic processing. We profiled a number of potential cleavage sites by signal peptidase and provided experimental confirmation of predicted cleavage sites of signal peptide. Furthermore, the present method uniquely represents the landscape of proteomic proteolytic processing rate during early embryogenesis in , revealing the underlying mechanism of stringent decay regulation of zygotically expressed proteins during early stages of embryogenesis.
蛋白质表达水平通过翻译和降解机制进行调节。降解中间产物的水平，即部分降解的蛋白质，不能通过全局蛋白质组学分析来区分，因为该分析定量了总蛋白质丰度水平。本研究旨在通过一种新的多重 N 端组学方法来开发一种评估通过蛋白水解加工进行降解调节的工具，该方法涉及蛋白质 N 末端的选择性等摩尔标记和标记的 N 末端肽的免疫亲和捕获。我们的方法不仅可以识别蛋白水解切割位点，还可以对蛋白水解加工进行高度多重化定量。我们通过信号肽酶对一些潜在的切割位点进行了分析，并对信号肽的预测切割位点进行了实验验证。此外，本方法还独特地描绘了 早期胚胎发生过程中的蛋白质组学蛋白水解加工速度的全貌，揭示了胚胎发生早期合子表达蛋白严格衰减调节的潜在机制。
