MicroRNA‐124a Inhibits Endoderm Lineage Commitment by Targeting Sox17 and Gata6 in Mouse Embryonic Stem Cells

MicroRNA‐124a Inhibits Endoderm Lineage Commitment by Targeting Sox17 and Gata6 in Mouse Embryonic Stem Cells:

microRNA‐124a was identified as a key repressor of endoderm lineage commitment in mouse embryonic stem cells. miR‐124a inhibits endoderm differentiation through targeting the 3' untranslated region (UTR) of Sox17 and Gata6, which are indispensable transcription factors for endoderm germ layer formation.

Abstract

The role of microRNAs (miRNAs) during mouse early development, especially in endoderm germ layer formation, is largely unknown. Here, via miRNA profiling during endoderm differentiation, we discovered that miR‐124a negatively regulates endoderm lineage commitment in mouse embryonic stem cells (mESCs). To further investigate the functional role of miR‐124a in early stages of differentiation, transfection of embryoid bodies (EBs) with miR‐124a mimic was performed. We showed that over‐expression of miR‐124a inhibits endoderm differentiation in vitro through targeting the 3′ untranslated region (UTR) of Sox17 and Gata6, revealing the existence of interplay between miR‐124a and the Sox17/Gata6 transcription factors in hepato‐specific gene regulation. In addition, we presented a feasible in vivo system that utilizes teratoma and gene expression profiling from microarray to quantitatively evaluate the functional role of miRNA in lineage specification. We demonstrated that ectopic expression of miR‐124a in teratomas by intra‐tumor delivery of miR‐124a mimic and Atelocollagen, significantly suppressed endoderm and mesoderm lineage differentiation while augmenting the differentiation into ectoderm lineage. Collectively, our findings suggest that miR‐124a plays a significant role in mESCs lineage commitment.

© AlphaMed Press 2019

Significance Statement

We discovered an additional role of miR‐124a in the early development of mESCs, on top of its widely reported role in neuronal fate determination. We demonstrated that miR‐124a negatively regulates endoderm lineage commitment in mESCs. Most of the studies reported on the effect of miRNA in stem cell differentiation were limited to in vitro analysis. In the current study, we presented a feasible strategy by utilizing teratoma as an in vivo system to quantitatively assess the functional role of miRNA in lineage specification through gene expression profiling. We believe this approach would be a useful addition to the currently available methods in the field of miRNA analysis in stem cell differentiation and lineage specification.