Claim: ADP-ribosylation factor 1 (ARF1), a member of the human gene family, encode small guanine nucleotide-binding proteins that stimulate the ADP-ribosyltransferase activity of cholera toxin.
Evidence: ADP-ribosylation factor 1 (ARF1) is a member of the human ARF gene family. The family members encode small guanine nucleotide-binding proteins that stimulate the ADP-ribosyltransferase activity of cholera toxin and play a role in vesicular trafficking as activators of phospholipase D.