ARF-PROTEIN ANTISENSE POTATO DISPLAYS STABLE - ADP-RIBOSYLATION OF 40KDA PROTEIN

GTP binding and ADP-ribosylation activities in transgenic ARF antisens e potato tuber were analyzed. Of proteins that bind GTP, only that wit h a molecular mass of 20.5kDa is ADP-ribosylated when potato extract i s incubated with [P-32] NAD either in the presence or absence of chole ra toxin. The decrease in ARF content resulted in an increase of the 4 0kDa protein ADP-ribosylation and a decrease in the modification of th e 42kDa polypeptide.