p75NTR functions in a complex with Nogo-66 receptor (NgR1) to mediate RhoA-dependent  inhibition of growth of regenerating axons exposed to inhibitory proteins of CNS myelin, such as Nogo, MAG or OMgP. Without p75NTR, OMgP can activate RhoA and inhibit CNS axon regeneration. Coexpression of p75NTR and OMgP suppress RhoA activation. A complex of NgR1, p75NTR and LINGO1 can activate RhoA.