“…For each of these protein species, the detailed information including spectrum index, retention time in minute, the precursor ion (isolation m/z , experimental m/z , theoretical m/z , z , IPMD in ppm, theoretical monoisotopic mass in Da), protein name, PTMs, number of matched product ions, P score, PTM score, and protein species score was provided in Table S1. It is worth mentioning that only 16 protein species were identified in the literature focusing on top‐down proteomics of histones from mouse …”