The calcium channel subunit gamma-4 is regulated by MafA and necessary for pancreatic beta-cell specification

Research output: Contribution to journalArticle

Abstract

Voltage-gated Ca2+ (CaV) channels trigger glucose-induced insulin secretion in pancreatic beta-cell and their dysfunction increases diabetes risk. These heteromeric complexes include the main subunit alpha1, and the accessory ones, including subunit gamma that remains unexplored. Here, we demonstrate that CaV gamma subunit 4 (CaVγ4) is downregulated in islets from human donors with diabetes, diabetic Goto-Kakizaki (GK) rats, as well as under conditions of gluco-/lipotoxic stress. Reduction of CaVγ4 expression results in decreased expression of L-type CaV1.2 and CaV1.3, thereby suppressing voltage-gated Ca2+ entry and glucose stimulated insulin exocytosis. The most important finding is that CaVγ4 expression is controlled by the transcription factor responsible for beta-cell specification, MafA, as verified by chromatin immunoprecipitation and experiments in beta-cell specific MafA knockout mice (MafAΔβcell). Taken together, these findings suggest that CaVγ4 is necessary for maintaining a functional differentiated beta-cell phenotype. Treatment aiming at restoring CaVγ4 may help to restore beta-cell function in diabetes.

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Subject classification (UKÄ) – MANDATORY

  • Cell and Molecular Biology
  • Endocrinology and Diabetes
Original languageEnglish
Article number106
JournalCommunications Biology
Volume2
Publication statusPublished - 2019 Mar 15
Publication categoryResearch
Peer-reviewedYes

Related research output

Cheng Luan, 2019, Lund: Lund University, Faculty of Medicine. 87 p.

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