title: Type XIV collagen, a new homotrimeric molecule extracted from fetal bovine skin and tendon, with a triple helical disulfide-bonded domain homologous to type IX and type XII collagens.
abstract: Previously undescribed disulfide-bonded collagenous pepsin-derived fragments have been isolated from fetal calf tendon and skin. One fragment, 10.5 kDa after reduction, was shown to be similar but distinct to the COL1 domain of the recently characterized type XII collagen (64% primary structure identity). The similarity includes important features such as size, location of the cysteine residues, and nature and position of an imperfection of the triple helix. From fetal calf skin, two approximately 34-kDa disulfide-bonded trimeric fragments were isolated in the unreduced form. Amino acid sequencing showed that one fragment contained solely the COL1 domain of type XII collagen while the other one only contained the COL1 domain of the new chain. Like type XII collagen, the new chain is therefore part of a homotrimeric molecule and should thus be considered as a distinct collagen type. We propose to call the molecule from which this fragment is derived, type XIV collagen, with a chain composition (alpha 1 (XIV]3. The presence of a domain similar to the COL1 domain of collagens types IX and XII suggests that type XIV collagen belongs to the group of fibril-associated collagens with interrupted triple helices (FACIT). Two other fragments, 13.5 and 17 kDa after reduction, were also purified. They were shown to contain the same triple helical domain with different pepsin cleavage sites at the amino terminus. Several tryptic peptides were sequenced, and the derived sequences could be aligned with the COL2 domain of type XII collagen or with flanking sequences in the NC2 and NC3 domains (61% sequence identity). These fragments are very likely to be also derived from type XIV collagen.
authors.affiliation: Institute for Biology and Chemistry of Proteins, Centre National de la Recherche Scientifique Unité Propre de Recherche 412), Université Claude Bernard, Villeurbanne, France.
authors.forename: B
authors.initials: B
authors.lastname: Dublet
authors.forename: M
authors.initials: M
authors.lastname: van der Rest
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D002645:Chickens; D002851:Chromatography, High Pressure Liquid; D003094:Collagen / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification; D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D004220:Disulfides / Q000032:analysis; D005333:Fetus; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010446:Peptide Fragments / Q000302:isolation & purification; D010449:Peptide Mapping; D011487:Protein Conformation; D012689:Sequence Homology, Nucleic Acid; D012867:Skin / Q000737:chemistry*; D013710:Tendons / Q000737:chemistry*
chemical_list: D004220:Disulfides; D046911:Macromolecular Substances; D010446:Peptide Fragments; D003094:Collagen; D004247:DNA