Sequence alignment of the FV and TFPIα basic regions. Shown are residues 995 to 1010 of human FV and 249 to 264 of human TFPIα, along with the corresponding sequences from other mammalian species. The homologous basic region is shaded gray. The conserved basic residues are blue; the conserved hydrophobic residues are orange. Mouse TFPIα contains the indicated 6-residue insertion in the basic region. Sequences were obtained from the NCBI, UniProt, and OMA databases.