Evidence for an Indirect Effect of Nerve Growth Factor (NGF) on the ADP-Ribosylation of a 22-kDa rho-like Protein in PC12 Cells

EDIN catalyzes the ADP-ribosylation of a 22 kDa protein, probably related to rho, in permeabilized PC12 cells in a time- and dose-dependent manner. Pre-treatment of the cells with nerve growth factor inhibits this EDIN-catalyzed ADP-ribosylation, both in vitro and in vivo . This inhibition is largely prevented by theaddition of K-252a. Nerve growth factor itself causes neither ADP- ribosylation nor phosphorylation of this 22 kDa protein. These results suggest that the ADP-ribosylation of the rho protein isinhibited, albeit indirectly, by nerve growth factor treatment.