The cyclin-dependent kinase inhibitor p27(Kip1) is a positive regulator of Schwann cell differentiation in vitro

Schwann cell precursors differentiating into a myelinating phenotype are critical for peripheral nerve development and regeneration. However, little is known about the underlying molecular mechanisms of Schwann cell differentiation. In the present study, we performed a cyclic adenosine monophosphate-induced Schwann cell differentiation model in vitro. Western blot analysis showed that p27^Kip1 expression was upregulated during the differentiation of Schwann cell, while the inhibition of p27^Kip1 expression by short hairpin RNA-mediated knockdown significantly abolished the expression of promyelinating markers and the alteration of cellular morphology. In addition, immunofluorescence revealed a decrease of p27^Kip1 nuclear staining and a concomitant increase of cytoplasmic staining in differentiated Schwann cells. In summary, our data indicated that p27^Kip1 was a positive regulator of Schwann cell differentiation in vitro.