Figure 6.

Alignments of the aptamer sequences yielded by the primary and secondary selections. The clone name is on the left, the number of occurrence of each sequence is mentioned when superior to one. The residues that do not vary in 95% of the sequences are shaded. Potentially paired nucleotides are underlined, and the paired regions are indicated by ‘Pn’ and an arrow at the top of each alignment. Alignments are based on sequence homology, potential pairings are sometimes slightly shifted from one clone to another. Arrows cover the whole region potentially involved in the pairing for all sequences. Primer sequences are in lower case letters and were not shaded even though they are invariant. They were omitted when not involved in potential pairings with a variable region, the number of nucleotides omitted is indicated in between brackets. The clones named ‘n+’ were selected under stringent conditions.