The role of microRNAs in embryonic stem cell development and differentiation

Abstract

Hundreds of microRNAs are expressed in mammalian cells where they modulate gene expression by mediating transcript cleavage and/or regulation of translation. However, the role of microRNAs in the regulation of stem cell growth and differentiation is not well understood. It was shown that miR-134 alone can enhance the differentiation of mESCs to ectodermal lineages; and modulate mESC differentiation through its potential to target and regulate multiple mRNAs. Experimental validation of rna22, a method for identifying microRNA binding sites and their corresponding heteroduplexes, is presented. The analysis suggests that some microRNAs may have as many as a few thousand targets, and provides the first examples of animal microRNAs targeting genes in their coding regions. The combined data imply that, by controlling specific genesets, microRNAs have a powerful influence on how mESCs sense and respond to their environment.