Novel miR-sc4 regulates the proliferation and migration of Schwann cells by targeting Cdk5r1

The proliferation and migration of Schwann cells are critical for the repair and regeneration of injured peripheral nerves. Noncoding RNAs, especially microRNAs (miRNAs), have been demonstrated to participate in regulating the biological behaviors of Schwann cells. Numerous differentially expressed novel miRNAs have been identified in the injured sciatic nerve stumps previously by Solexa sequencing. In the current research, we studied the biological function of a novel miRNA, miR-sc4, in detail. Outcomes from proliferation and migration assays suggested that miR-sc4 played an inhibitory role on the proliferation and migration of Schwann cells. Results from bioinformatic analysis, luciferase reporter assay, and rescue experiments suggested that miR-sc4 executed its effect through directly targeting cyclin-dependent kinase 5 activator 1 (Cdk5r1). Collectively, our current study revealed the biological functions of a novel miRNA, showed the effect of miR-sc4 in Schwann cell phenotypic changes, and thus indicated the involvement of miRNAs in peripheral nerve repair and regeneration.