Decay accelerating factor (DAF) peptide sequences share homology with a consensus sequence found in the superfamily of structurally related complement proteins and other proteins including haptoglobin, factor XIII, beta 2-glycoprotein I, and the IL-2 receptor.
Amino acid sequence data derived from tryptic peptides of the decay accelerating factor indicate that this complement regulatory protein contains a sequence with homology to the superfamily of structurally related complement proteins, including the C4 binding protein, factor H, complement receptor type 1, complement receptor type 2, Ba, C1r, and to their non-complement relatives, including beta 2-glycoprotein I, factor XIIIb, the alpha 1 chain of haptoglobin, and the interleukin 2 receptor. Identifying DAF as a member of the superfamily of structurally related complement proteins provides evidence that DAF may contain a functionally important C4b and C3b binding domain.
D000595:Amino Acid Sequence; D018958:CD55 Antigens; D002851:Chromatography, High Pressure Liquid; D005176:Factor XIII / Q000032:analysis; D006023:Glycoproteins / Q000032:analysis; D006242:Haptoglobins / Q000032:analysis; D006801:Humans; D008565:Membrane Proteins / Q000032:analysis*; D010446:Peptide Fragments / Q000032:analysis*; D011951:Receptors, Complement / Q000032:analysis; D011971:Receptors, Immunologic / Q000032:analysis; D015375:Receptors, Interleukin-2; D014357:Trypsin; D053482:beta 2-Glycoprotein I
D018958:CD55 Antigens; D006023:Glycoproteins; D006242:Haptoglobins; D008565:Membrane Proteins; D010446:Peptide Fragments; D011951:Receptors, Complement; D011971:Receptors, Immunologic; D015375:Receptors, Interleukin-2; D053482:beta 2-Glycoprotein I; D005176:Factor XIII; D014357:Trypsin