首页    期刊浏览 2024年11月28日 星期四
登录注册

文章基本信息

  • 标题:Isoform-specific antagonists of exchange proteins directly activated by cAMP
  • 本地全文:下载
  • 作者:Tamara Tsalkova ; Fang C. Mei ; Sheng Li
  • 期刊名称:Proceedings of the National Academy of Sciences
  • 印刷版ISSN:0027-8424
  • 电子版ISSN:1091-6490
  • 出版年度:2012
  • 卷号:109
  • 期号:45
  • 页码:18613-18618
  • DOI:10.1073/pnas.1210209109
  • 语种:English
  • 出版社:The National Academy of Sciences of the United States of America
  • 摘要:The major physiological effects of cAMP in mammalian cells are transduced by two ubiquitously expressed intracellular cAMP receptors, protein kinase A (PKA) and exchange protein directly activated by cAMP (EPAC), as well as cyclic nucleotide-gated ion channels in certain tissues. Although a large number of PKA inhibitors are available, there are no reported EPAC-specific antagonists, despite extensive research efforts. Here we report the identification and characterization of noncyclic nucleotide EPAC antagonists that are exclusively specific for the EPAC2 isoform. These EAPC2-specific antagonists, designated as ESI-05 and ESI-07, inhibit Rap1 activation mediated by EAPC2, but not EPAC1, with high potency in vitro. Moreover, ESI-05 and ESI-07 are capable of suppressing the cAMP-mediated activation of EPAC2, but not EPAC1 and PKA, as monitored in living cells through the use of EPAC- and PKA-based FRET reporters, or by the use of Rap1-GTP pull-down assays. Deuterium exchange mass spectroscopy analysis further reveals that EPAC2-specific inhibitors exert their isoform selectivity through a unique mechanism by binding to a previously undescribed allosteric site: the interface of the two cAMP binding domains, which is not present in the EPAC1 isoform. Isoform-specific EPAC pharmacological probes are highly desired and will be valuable tools for dissecting the biological functions of EPAC proteins and their roles in various disease states.
  • 关键词:cAMP-regulated guanine nucleotide exchange factor ; high-throughput screening ; hydrogen/deuterium exchange mass spectrometry
国家哲学社会科学文献中心版权所有