m 6 A mRNA Methylation Regulates Human β-Cell Biology in Physiological States and in Type 2 Diabetes

Nat Metab. 2019 Aug;1(8):765-774. doi: 10.1038/s42255-019-0089-9. Epub 2019 Jul 29.

Abstract

The regulation of islet cell biology is critical for glucose homeostasis1.N6 -methyladenosine (m6A) is the most abundant internal messenger RNA (mRNA) modification in mammals2. Here we report that the m6A landscape segregates human type 2 diabetes (T2D) islets from controls significantly better than the transcriptome and that m6A is vital for β-cell biology. m6A-sequencing in human T2D islets reveals several hypomethylated transcripts involved in cell-cycle progression, insulin secretion, and the Insulin/IGF1-AKT-PDX1 pathway. Depletion of m6A levels in EndoC-βH1 induces cell-cycle arrest and impairs insulin secretion by decreasing AKT phosphorylation and PDX1 protein levels. β-cell specific Mettl14 knock-out mice, which display reduced m6A levels, mimic the islet phenotype in human T2D with early diabetes onset and mortality due to decreased β-cell proliferation and insulin degranulation. Our data underscore the significance of RNA methylation in regulating human β-cell biology, and provide a rationale for potential therapeutic targeting of m6A modulators to preserve β-cell survival and function in diabetes.

Publication types

  • Letter
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Diabetes Mellitus, Type 2 / physiopathology*
  • Humans
  • Insulin Secretion
  • Insulin-Secreting Cells / physiology*
  • Methylation
  • RNA, Messenger / metabolism*

Substances

  • RNA, Messenger