Retinoid acid-induced microRNA-31-5p suppresses myogenic proliferation and differentiation by targeting CamkIIδ

Background We previously reported that Wnt5a/CaMKIIδ (calcium/calmodulin-dependent protein kinase II delta) pathway was involved in the embryonic tongue deformity induced by excess retinoic acid (RA). Our latest study found that the expression of miR-31-5p , which was predicted to target the 3′UTR of CamkIIδ , was raised in the RA-treated embryonic tongue. Thus, we hypothesized that the excess RA regulated Wnt5a/CaMKIIδ pathway through miR-31-5p in embryonic tongue. Methods C2C12 myoblast line was employed as an in vitro model to examine the suppression of miR-31-5p on CamkIIδ expression, through which RA impaired the myoblast proliferation and differentiation in embryonic tongue. Results RA stimulated the expression of miR-31-5p in both embryonic tongue and C2C12 myoblasts. Luciferase reporter assay confirmed that the 3′UTR of CamkIIδ was a target of miR-31-5p. MiR-31-5p mimics disrupted CamkIIδ expression, C2C12 proliferation and differentiation as excess RA did, while miR-31-5p inhibitor partially rescued these defects in the presence of RA. Conclusions Excess RA can stimulate miR-31-5p expression to suppress CamkIIδ , which represses the proliferation and differentiation of tongue myoblasts.