SEQUENCE OF CANINE COL1A2 CDNA - NUCLEOTIDE SUBSTITUTIONS AFFECTING THE CYANOGEN-BROMIDE PEPTIDE MAP OF THE ALPHA-2(I) CHAIN

The alpha 2 chain of canine type I collagen was characterized with bot h sequence analysis of COL1A2 cDNA and chemical analysis of alpha 2(I) chains. The complete sequence of canine COL1A2 cDNA was determined fr om reverse-transcribed and polymerase chain reaction-amplified total R NA from cultured skin fibroblasts. Pepsin-digested and cyanogen bromid e-digested type I collagen peptides were analyzed with chromatography, gel electrophoresis, and mass spectrometry. Identity between the sequ ences of canine and human COL1A2 cDNA was 90.9%, predicting conservati on of the 3 cysteine residues required for C-propeptide registration a nd of cleavage sites for signal peptidase, procollagen N-proteinase, v ertebrate collagenase, and procollagen C-proteinase. Conservation of a ll 50 lysine residues was also predicted, including preservation of th e 1:2 asymmetry in the X:Y distribution of the 31 lysine residues in t he alpha 2(I) triple helix. The human and canine sequences differed in the location of Y-position proline residues and the presence of two u nique canine cyanogen bromide peptides, alpha 2 CB3b and alpha 2 CB3c, 5. Knowledge of the conserved and unique features of canine COL1A2 wil l be valuable for analysis of the expression, synthesis, and structure of type I collagen as well as studies of canine osteogenesis imperfec ta. (C) 1998 Academic Press.