Homologous 3′-terminal regions of mRNAs for surface antigens of different antigenic variants of Trypanosoma brucei

Abstract
Sequences corresponding to the complete 3′-terminal regions of the messenger RNAs for three different Variant Surface Glycoproteins of Trypanosoma brucei were determined on complementary DNA inserts cloned in recombinant plasmids. The three sequences show 80-130 base pair long segments of strong (70-80%) homology at the 3′ ends, whereas the regions upstream from the last 130-140 base pairs contain no significant homology. The signal AAUAAA, present near the 3′ ends of almost all known polyadenylated mRNAs of eukaryotes, does not occur in the 3′-terminal sequences of these three variants.