Figure 1

Definition of conserved and non-conserved polyadenylation sites. Cleavage sites are shown by flags and polyadenylation signals are shown by black squares. (A) sites are within 30 bp of each other and aligned associated signals: conserved; (B) sites are within 30 bp of each other, however, their associated signals are not aligned: non conserved; (C) although the sites themselves are aligned, their signals are not: non conserved.