세포내 총체적인 인산화 펩타이드 및 인산화 위치 규명을 위해 질량분석기 전 단계의 C4 및 양이온 교환수지 칼럼 이용 방법의 비교

作者：김혜정; 백문창

来源：약학회지, 2015, 59(3): 113-119.

DOI：10.17480/psk.2015.59.3.113

• Phosphorylation network
• Kinase-substrate relationships (KSRs)
• Network module
• Conservation
• phosphopeptide
• mass spectrometry
• strong cation ion exchange
• C4 column
• <TEX>$TiO_2$</TEX>

Protein phosphorylation is one of most important post-translational modifications (PTMs) and plays an important role in regulation of protein function. Here we develop a method for a global identification of phosphopeptides and phosphorylation sites using nano-LC MS/MS. We compared two separation methods, C4 and strong cation ion exchange (SCX). Before phosphopeptides enrichment with <TEX>$TiO_2$</TEX>, total proteins from Rat 1 cells have been separated using C4 column or tryptic peptides of proteins from the cells have been separated using SCX column. Finally, we have detected 52 phosphorylation sites on 41 proteins from SCX method and 375 phosphorylation sites on 252 proteins from C4 method, and determined the function and localization of identified phosphoproteins using DAVID software. In particular, we showed new phosphorylation sites from membrane proteins related to various cell signaling mechanisms. This method may contribute to study global signal networks induced by various signals including ligands and drugs.