Endosomal GPCR signaling turned off by negative feedback actions of PKA and v-ATPase.
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ABSTRACT:
SUBMITTER: Gidon A
PROVIDER: S-EPMC4138287 | biostudies-literature | 2014 Sep
REPOSITORIES: biostudies-literature
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Endosomal GPCR signaling turned off by negative feedback actions of PKA and v-ATPase.
Gidon Alexandre A Al-Bataineh Mohammad M MM Jean-Alphonse Frederic G FG Stevenson Hilary P HP Watanabe Tomoyuki T Louet Claire C Khatri Ashok A Calero Guillermo G Pastor-Soler Núria M NM Gardella Thomas J TJ Vilardaga Jean-Pierre JP
Nature chemical biology 20140727 9
The PTH receptor is to our knowledge one of the first G protein-coupled receptor (GPCR) found to sustain cAMP signaling after internalization of the ligand-receptor complex in endosomes. This unexpected model is adding a new dimension on how we think about GPCR signaling, but its mechanism is incompletely understood. We report here that endosomal acidification mediated by the PKA action on the v-ATPase provides a negative feedback mechanism by which endosomal receptor signaling is turned off. ...[more]
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