Spatially compartmentalized phase regulation of a Ca²⁺-cAMP-PKA oscillatory circuit.

ABSTRACT: Signaling networks are spatiotemporally organized to sense diverse inputs, process information, and carry out specific cellular tasks. In ? cells, Ca²⁺, cyclic adenosine monophosphate (cAMP), and Protein Kinase A (PKA) exist in an oscillatory circuit characterized by a high degree of feedback. Here, we describe a mode of regulation within this circuit involving a spatial dependence of the relative phase between cAMP, PKA, and Ca²⁺. We show that in mouse MIN6 ? cells, nanodomain clustering of Ca²⁺-sensitive adenylyl cyclases (ACs) drives oscillations of local cAMP levels to be precisely in-phase with Ca²⁺ oscillations, whereas Ca²⁺-sensitive phosphodiesterases maintain out-of-phase oscillations outside of the nanodomain. Disruption of this precise phase relationship perturbs Ca²⁺ oscillations, suggesting the relative phase within an oscillatory circuit can encode specific functional information. This work unveils a novel mechanism of cAMP compartmentation utilized for localized tuning of an oscillatory circuit and has broad implications for the spatiotemporal regulation of signaling networks.

SUBMITTER: Tenner B 

PROVIDER: S-EPMC7671691 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature