Repulsive migration of Schwann cells induced by Slit-2 through Ca2+-dependent RhoA-myosin signaling

Abstract

Schwann cells migrate along axons before initiating myelination during development and their migration facilitates peripheral nerve regeneration after injury. Axon guidance molecule Slit-2 is highly expressed during peripheral development and nerve regeneration; however, whether Slit-2 regulates the migration of Schwann cells remains a mystery. Here we show that Slit-2 receptor Robo-1 and Robo-2 were highly expressed in Schwann cells in vitro and in vivo. Using three distinct migration assays, we found that Slit-2 repelled the migration of cultured Schwann cells. Furthermore, frontal application of a Slit-2 gradient to migrating Schwann cells first caused the collapse of leading front, and then reversed soma translocation of Schwann cells. The repulsive effects of Slit-2 on Schwann cell migration depended on a Ca(2+) signaling release from internal stores. Interestingly, in response to Slit-2 stimulation, the collapse of leading front required the loss of F-actin and focal adhesion, whereas the subsequent reversal of soma translocation depended on RhoA-Rock-Myosin signaling pathways. Taken together, we demonstrate that Slit-2 repels the migration of cultured Schwann cells through RhoA-Myosin signaling pathways in a Ca(2+)-dependent manner.