Amino acid sequence lineups of human FVIII with other A domain proteins. (A through C) Alignment of human FVIII A1 (A), A2 (B), and A3 (C) domains with hCp, showing SCR and VR placing together with conserved residues. Lowercase, Vrs; uppercase with bar above sequence, SCRs. Sequence numberings refer to the mature proteins. (D through F ) Alignment of A1 (D), A2 (E), and A3 (F ) domain sequences of: human and mouse FVIII (humf8,murf8); human and bovine FV (humfv,bovfv); rat and human Cp (ratcp,humcp), showing extent of conservation of human FVIII residues with these related proteins. Key: white characters on black background, identical in all six sequences; white on grey, residues identical to that in human FVIII; black on grey, residue similar to that in human FVIII; black on white, residues dissimilar to human FVIII.