the stimulation was specific for gtp , since many other nucleotides ( e.g . atp , gdp , and itp ) and gtp analogues ( guanosine 5'-o- ( 3-thiotriphosphate and guanosine 5'- ( beta , gamma-imino ) triphosphate ) had no effect .
C0018353
gtp
C0079469
guanosine