HETEROTRIMERIC GUANINE-NUCLEOTIDE-BINDING PROTEINS IN EUKARYOTIC PARASITES

Parasites, in order to survive, must be able to recognize and respond to signals in their environment. This is particularly so when parasite development is associated with moving from one environment to another as it is likely that a rapid process of adaptation that requires chan ges in gene expression will have to be initiated. In general, interact ion with host signals takes place at the parasite surface, with the re sulting need for information to be transmitted to the interior. Many s uch signalling events in mammalian cells are regulated by a family of molecules referred to as guanine nucleotide-binding proteins (G protei ns). The structure and function of these molecules, and evidence obtai ned to date of the roles that they may play in parasitic organisms, ar e discussed here by Bill and Maggie Harnett.