... investigated the roles of RhoA-kinase and myosin II in semaphorin-3A-induced growth cone collapse and axon retraction. I report that semaphorin 3A activates myosin II in growth cones and axons. Myosin II activity is required for axon retraction but not growth cone collapse. Furthermore, semaphorin 3A promotes...

... to the ephrin inhibitory effects on COS cell migration and to ephrin-dependent growth cone collapse in primary neurons. Therefore, Eph receptors can regulate R-Ras in two different ways to achieve cell repulsion. We found that EphA as well as EphB receptor stimulation by ephrins decreases the levels of R...