Fig. 4. Analysis of consensus nucleotide sequences of specific aptamers that bind to the HA9 peptide. (A) The common consensus sequence was obtained by the arrangement of specific sequences of 6 aptamers from groups B and C. The bold letters are used to indicate the consensus sequences that are conserved in more than five aptamers, and the dashed letters indicate the sequences conserved in more than three aptamers. N represents the non-consensus sequence. (B) The predicted stem-and-loop structure of C7-35M aptamer containing the consensus sequences and a part of the 3′ primer region. The nucleotides in the circles indicate the conserved sequences represented as bold letters in (A). (C) The analysis of relative binding affinity to the H9 peptide. The equal amount of cell lysates and H9 peptide was separated in duplicate, and then hybridized with mouse anti-H9 peptide antibody or C7-35M oligomer for each duplicate. The relative density was electronically determined by ImageJ software from NIH Image. (D) The relative binding affinities of C7-35M, chicken anti-virus and mouse anti-H9 peptide antibody to the viral particles.