CD loops of chicken eight-exon clade B serpins. For the serpinb14 (ovalbumin) group, identical residues in the loop are highlighted in yellow. For the SERPINB10 group, nuclear-localization signals or related motif (chicken serpinb10) are indicated in blue. The AT-rich DNA-binding motif, present only in MENT, is underlined. For the SERPINB2 orthologues, glutamine residues required for crosslinking of human SERPINB2/PAI-2 are highlighted in green. In standard numbering, based on α1-antitrypsin, the CD loop replaces amino acids 84–87.