▁g yl cop rote in ▁( MA G ) ▁bind ▁Ng R ▁and ▁not ▁p 7 5 . ▁ ▁The ▁re ceptor ▁p 7 5 ▁la cks ▁a ▁binding ▁domain ▁for ▁either ▁of ▁these ▁prote ins . ▁ ▁Activ ation ▁of ▁r ho ▁protein ▁ ▁The ▁work ▁of ▁Kap lan ▁and ▁Miller < ▁shows ▁that ▁there ▁is ▁an ▁interaction ▁between ▁the ▁p 7 5 / N g R ▁re cept ors ▁and ▁R ho ▁G DP ▁dis soci ation ▁in hib itor ▁( R ho - G DI ). ▁ ▁Kap lan ▁and ▁Miller ▁show ▁that ▁when ▁N ogo ▁is ▁bound ▁to ▁Ng R , ▁R ho - G DI ▁is ▁associated ▁with ▁p 7 5 . ▁ ▁When ▁R ho - G DI ▁is ▁drawn ▁to ▁p 7 5 ▁it ▁is ▁no ▁longer ▁bound ▁to ▁R ho - G DP . ▁ ▁This ▁allows ▁for ▁G TP ▁to ▁be ▁ex changed ▁for ▁G DP ▁activ ating ▁the ▁R ho ▁protein . ▁ ▁R ho - G TP , ▁a ▁R ho ▁G TP ase , ▁then ▁activ ates ▁RO CK ▁which ▁ph osph ory l ates ▁other ▁prote ins ▁which ▁in hib it ▁neur ite ▁out g row th . ▁ ▁When ▁N ogo ▁is ▁not ▁bound ▁to ▁Ng R , ▁p 7 5 ▁is ▁not ▁activ ated ▁and ▁R ho - G DI ▁remains ▁bound ▁to ▁R ho - G DP . ▁ ▁The ▁R ho ▁protein ▁remains ▁bound ▁with ▁G DP ▁and ▁remains ▁in active . ▁ ▁RO CK ▁therefore