The Lin28/let-7 Axis Regulates Glucose Metabolism

Cell. 2011 Sep 30;147(1):81-94. doi: 10.1016/j.cell.2011.08.033.

Abstract

The let-7 tumor suppressor microRNAs are known for their regulation of oncogenes, while the RNA-binding proteins Lin28a/b promote malignancy by inhibiting let-7 biogenesis. We have uncovered unexpected roles for the Lin28/let-7 pathway in regulating metabolism. When overexpressed in mice, both Lin28a and LIN28B promote an insulin-sensitized state that resists high-fat-diet induced diabetes. Conversely, muscle-specific loss of Lin28a or overexpression of let-7 results in insulin resistance and impaired glucose tolerance. These phenomena occur, in part, through the let-7-mediated repression of multiple components of the insulin-PI3K-mTOR pathway, including IGF1R, INSR, and IRS2. In addition, the mTOR inhibitor, rapamycin, abrogates Lin28a-mediated insulin sensitivity and enhanced glucose uptake. Moreover, let-7 targets are enriched for genes containing SNPs associated with type 2 diabetes and control of fasting glucose in human genome-wide association studies. These data establish the Lin28/let-7 pathway as a central regulator of mammalian glucose metabolism.

Publication types

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

MeSH terms

  • Animals
  • Diabetes Mellitus, Type 2 / metabolism
  • Gene Expression Regulation
  • Genome-Wide Association Study
  • Glucose / metabolism*
  • Humans
  • Insulin Resistance
  • Mice
  • Mice, Knockout
  • Mice, Transgenic
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Obesity / genetics
  • Obesity / metabolism
  • RNA-Binding Proteins / genetics
  • RNA-Binding Proteins / metabolism

Substances

  • Lin-28 protein, mouse
  • MicroRNAs
  • RNA-Binding Proteins
  • mirnlet7 microRNA, mouse
  • Glucose