【摘要】：正Olfactory ensheathing cells(OECs) migrate from the olfactory epithelium towards the olfactory bulb during development.However,the guidance mechanism for OEC migration remains a mystery.Here we show that migrating OECs expressed the receptor of the repulsive guidance factor Slit-2.A gradient of Slit-2 in front of cultured OECs first caused the collapse of the leading front,then the reversal of cell migration.These Slit-2 effects depended on the Ca~(2+) release from internal stores through IP3 receptor channels.Interestingly,in response to Slit-2 stimulation,collapse of the leading front required the activation of the F-actin severing protein cofilin in a Ca~(2+)- dependent manner,whereas the subsequent reversal of the soma migration depended on the reversal of RhoA activity across the cell.Finally,the Slit-2-induced repulsion of cell migration was fully mimicked by co-application of inhibitors of F-actin polymerization and RhoA kinase.Our findings revealed Slit-2 as a repulsive guidance factor for OEC migration and an unexpected link between Ca~(2+) and cofilin signaling during Slit-2-triggered repulsion.