Dissociation of inositol 1,4,5-trisphosphate from IP₃ receptors contributes to termination of Ca²⁺ puffs.

ABSTRACT: Ca²⁺ puffs are brief, localized Ca²⁺ signals evoked by physiological stimuli that arise from the coordinated opening of a few clustered inositol 1,4,5-trisphosphate receptors (IP₃Rs). However, the mechanisms that control the amplitude and termination of Ca²⁺ puffs are unresolved. To address these issues, we expressed SNAP-tagged IP₃R3 in HEK cells without endogenous IP₃Rs and used total internal reflection fluorescence microscopy to visualize the subcellular distribution of IP₃Rs and the Ca²⁺ puffs that they evoke. We first confirmed that SNAP-IP₃R3 were reliably identified and that they evoked normal Ca²⁺ puffs after photolysis of a caged analog of IP₃. We show that inc

SUBMITTER: Smith HA 

PROVIDER: S-EPMC9971896 | biostudies-literature | 2023 Feb

REPOSITORIES: biostudies-literature