Dynamic Ca2+-Dependent Transcription Links Metabolic Stress to Impaired β-Cell Identity.

Abstract

This study was undertaken to establish a temporal link between an increase in intracellular Ca2+ concentration and the loss of pancreatic β-cell identity. We profiled the alterations in Ca2+ dynamics and gene transcription that occur in freshly isolated islets following membrane depolarization. We show that initially adaptive Ca2+-dependent transcription changes, mediated largely by CREB and CREB-dependent transcription factors, rapidly become maladaptive, causing the loss of β-cell identity and function. We also show that many effector genes linked to nearby human type 2 diabetes susceptibility loci are regulated by Ca2+-dependent mechanisms.