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A circular RNA generated from an intron of the insulin gene controls insulin secretion

ABSTRACT: Fine-tuning of insulin release from pancreatic β-cells is essential to maintain blood glucose homeostasis. Here, we report that insulin secretion is regulated by a circular RNA containing the lariat sequence of the second intron of the insulin gene. Silencing of this intronic circular RNA in pancreatic islets leads to a decrease in the expression of key components of the secretory machinery of β-cells, resulting in impaired glucose- or KCl-induced insulin release and calcium signaling. The effect of the circular RNA is exerted at the transcriptional level and involves an interaction with the RNA-binding protein TAR DNA-binding protein 43 kDa (TDP-43). The level of this circularized intron is reduced in the islets of rodent diabetes models and of type 2 diabetic patients, possibly explaining their impaired secretory capacity. The study of this and other circular RNAs helps understanding β-cell dysfunction under diabetes conditions, and the etiology of this common metabolic disorder.

ORGANISM(S): Rattus norvegicus

PROVIDER: GSE134699 | GEO | 2020/09/21

REPOSITORIES: GEO

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miR-7a is regulated in beta-cell dysfunction and couples early and late stages of pancreatic beta-cell differentiation to insulin secretion

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