IGF2-produced microRNA restricts growth via suppression of IGF1

Abstract

Insulin-like growth factor 1 (IGF1) is a key protein that contributes to control of an organism’s size after birth and during development, whereas IGF2 is the main regulator of growth and body size during fetal development. A study in Cell Reports describes a mechanism by which a microRNA produced from Igf2 regulates IGF1 to suppress growth in mice.

The researchers then assessed the effect of miR-483 on fetal and postnatal development and growth. “We made a knockout mouse and two types of mouse lines that make more copies of miR-483 than the normal levels; one coming from the ‘endogenous’ location at the Igf2 gene and one from another genomic location,” says corresponding author Miguel Constância. Knockout of miR483 (Mir483^Pat-KO mice) did not result in a noticeable phenotypic change. Overexpression of Mir-483 during fetal development, however, universally led to fetal death.