Steady-state regulation of COPII-dependent secretory cargo sorting by inositol trisphosphate receptors, calcium, and penta EF hand proteins.

ABSTRACT: Recently, we demonstrated that agonist-stimulated Ca²⁺ signaling involving IP3 receptors modulates ER export rates through activation of the penta-EF Hand proteins apoptosis-linked gene-2 (ALG-2) and peflin. It is unknown, however, whether IP3Rs and penta-EF proteins regulate ER export rates at steady state. Here we tested this idea in normal rat kidney epithelial cells by manipulation of IP3R isoform expression. Under standard growth conditions, spontaneous cytosolic Ca²⁺ oscillations occurred simultaneously in successive groups of contiguous cells, generating intercellular Ca²⁺ waves that moved across the monolayer periodically. Depletion of IP3R-3, typically the least promiscuous IP3R isoform, caused increased cell participation in intercellular Ca²

SUBMITTER: Held A 

PROVIDER: S-EPMC10750190 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature