RyR2/IRBIT regulates insulin gene transcript, insulin content, and secretion in the insulinoma cell line INS-1.

ABSTRACT: The role of ER Ca²⁺ release via ryanodine receptors (RyR) in pancreatic β-cell function is not well defined. Deletion of RyR2 from the rat insulinoma INS-1 (RyR2^KO) enhanced IP₃ receptor activity stimulated by 7.5 mM glucose, coincident with reduced levels of the protein IP₃ Receptor Binding protein released with Inositol 1,4,5 Trisphosphate (IRBIT). Insulin content, basal (2.5 mM glucose) and 7.5 mM glucose-stimulated insulin secretion were reduced in RyR2^KO and IRBIT^KO cells compared to controls. INS2 mRNA levels were reduced in both RyR2^KO and IRBIT^KO cells, but INS1 mRNA levels were specifically decreased in RyR2^KO cells. Nuclear localization of S-adenosylhomocysteinase (AHCY) was increas

SUBMITTER: Harvey KE 

PROVIDER: S-EPMC9095623 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature