title: Complete coding sequence of bovine aggrecan: comparative structural analysis.
abstract: The previously available sequence for bovine aggrecan included only the KS domain, the C-terminal portion of the CS-2 domain, and the entire CS-3 and G3 domains. We have isolated cDNA clones for previously uncharacterized portions of the bovine aggrecan sequence, and, when we combined them with previously published incomplete sequences, have obtained a complete sequence for the entire core protein. The bovine aggrecan sequence, which is a composite of new sequence data and previously published incomplete sequences, is 2327 residues in length. Although there is significant conservation of G1, G2, and G3 globular domains between species, there are differences in the length of the interglobular domain, in the number of KS domain hexapeptide repeats and CS domain repeats, and in alternative splicing within the G3 domain. The bovine aggrecan KS domain contains 24 repeats of a hexapeptide motif. The largely uncharacterized CS-1 domain of bovine aggrecan was found to contain 27 variable repeats of a 21-residue consensus sequence. A notable feature of the bovine CS-1 domain is in the distribution of single Ser-Gly dipeptides, the majority of which are separated by 7 or 8 amino acids, compared to the human, where discrete pairs of Ser-Gly dipeptides are separated by 13 amino acids. The CS-2 domain contains a total of six "homology domains" with 4 complete and 2 partial approximately 100-residue repeats. Each "homology domain" contains a "nodal" region with few sites for CS chain addition that is highly conserved between species, suggesting a possible role in aggrecan biosynthesis or catabolism.
authors.affiliation: Department of Medicine, Case Western Reserve University, Cleveland, Ohio 44106-4946, USA. tmh@po.CWRU.Edu
authors.forename: T M
authors.initials: TM
authors.lastname: Hering
authors.forename: J
authors.initials: J
authors.lastname: Kollar
authors.forename: T D
authors.initials: TD
authors.lastname: Huynh
mesh_terms: D053674:Aggrecans; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002358:Cartilage, Articular / Q000737:chemistry; D002417:Cattle; D002809:Chondroitin Sulfates / Q000737:chemistry; D016384:Consensus Sequence; D017124:Conserved Sequence; D018076:DNA, Complementary / Q000235:genetics; D016326:Extracellular Matrix Proteins; D015723:Gene Library; D007632:Keratan Sulfate / Q000235:genetics; D037181:Lectins, C-Type; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011509:Proteoglycans / Q000235:genetics*; D012091:Repetitive Sequences, Nucleic Acid; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity
chemical_list: D053674:Aggrecans; D018076:DNA, Complementary; D016326:Extracellular Matrix Proteins; D037181:Lectins, C-Type; D011509:Proteoglycans; D002809:Chondroitin Sulfates; D007632:Keratan Sulfate