期刊
BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS
卷 1834, 期 6, 页码 1215-1221出版社
ELSEVIER
DOI: 10.1016/j.bbapap.2013.02.028
关键词
Dynamics; CAMP; Phosphodiesterase; Complexes; Signal termination
资金
- Mechanobiology Institute, National University of Singapore, Singapore
- Ministry of Education Tier 1, Singapore
- Waters Corporation, Milford, MA
cAMP signaling is a fundamental cellular process necessary for mediating responses to hormonal stimuli. In contrast to cAMP-dependent activation of protein kinase A (PI(A), an important cellular target, far less is known on termination in CAMP signaling, specifically how phosphodiesterases (PDEs) facilitate dissociation and hydrolysis of bound cAMP. In this study, we have probed the dynamics of a ternary complex of PICA and a PDE-RegA with an excess of a PDE-nonhydrolyzable cAMP analog, Sp-cAMPS by amide hydrogen/deuterium exchange mass spectrometry (HDXMS). Our results highlight how HDXMS can be used to monitor reactions together with mapping conformational dynamics of transient signaling complexes. Our results confirm a two-state model for active RegA-mediated dissociation of bound CAMP. Further, our results reveal that Sp-cAMPS and RegA mediate mutually exclusive interactions with the same region of PICA and at specific concentrations of Sp-cAMPS, RegA is capable of blocking Sp-cAMPS reassociation to PICA. This provides a molecular basis for how PDEs modulate levels of intracellular cAMP so that PICA is better suited to responding to fluxes rather than constant levels of cAMP. This study underscores how HDXMS can be a powerful tool for monitoring reactions together with mapping conformational dynamics in signaling proteins. This article is part of a Special Issue entitled: Mass spectrometry in structural biology. (C) 2013 Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据