title: Sequence and structural implications of a bovine corneal keratan sulfate proteoglycan core protein. Protein 37B represents bovine lumican and proteins 37A and 25 are unique.
abstract: Amino acid sequence from tryptic peptides of three different bovine corneal keratan sulfate proteoglycan (KSPG) core proteins (designated 37A, 37B, and 25) showed similarities to the sequence of a chicken KSPG core protein lumican. Bovine lumican cDNA was isolated from a bovine corneal expression library by screening with chicken lumican cDNA. The bovine cDNA codes for a 342-amino acid protein, M(r) 38,712, containing amino acid sequences identified in the 37B KSPG core protein. The bovine lumican is 68% identical to chicken lumican, with an 83% identity excluding the N-terminal 40 amino acids. Location of 6 cysteine and 4 consensus N-glycosylation sites in the bovine sequence were identical to those in chicken lumican. Bovine lumican had about 50% identity to bovine fibromodulin and 20% identity to bovine decorin and biglycan. About two-thirds of the lumican protein consists of a series of 10 amino acid leucine-rich repeats that occur in regions of calculated high beta-hydrophobic moment, suggesting that the leucine-rich repeats contribute to beta-sheet formation in these proteins. Sequences obtained from 37A and 25 core proteins were absent in bovine lumican, thus predicting a unique primary structure and separate mRNA for each of the three bovine KSPG core proteins.
authors.affiliation: Division of Biology, Kansas State University, Manhattan 66506.
authors.forename: J L
authors.initials: JL
authors.lastname: Funderburgh
authors.forename: M L
authors.initials: ML
authors.lastname: Funderburgh
authors.forename: S J
authors.initials: SJ
authors.lastname: Brown
authors.forename: J P
authors.initials: JP
authors.lastname: Vergnes
authors.forename: J R
authors.initials: JR
authors.lastname: Hassell
authors.forename: M M
authors.initials: MM
authors.lastname: Mann
authors.forename: G W
authors.initials: GW
authors.lastname: Conrad
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002417:Cattle; D002478:Cells, Cultured; D002645:Chickens; D011508:Chondroitin Sulfate Proteoglycans / Q000737:chemistry / Q000235:genetics*; D003315:Cornea / Q000378:metabolism*; D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D015723:Gene Library; D007632:Keratan Sulfate / Q000737:chemistry / Q000235:genetics*; D000071234:Lumican; D008297:Male; D008969:Molecular Sequence Data; D016296:Mutagenesis; D009919:Orchiectomy; D010446:Peptide Fragments / Q000302:isolation & purification; D010957:Plasmids; D011061:Poly A / Q000235:genetics / Q000302:isolation & purification; D017433:Protein Structure, Secondary; D012333:RNA, Messenger / Q000235:genetics / Q000302:isolation & purification; D012091:Repetitive Sequences, Nucleic Acid; D015183:Restriction Mapping; D017384:Sequence Deletion; D017386:Sequence Homology, Amino Acid; D014357:Trypsin
chemical_list: D011508:Chondroitin Sulfate Proteoglycans; D000071234:Lumican; D010446:Peptide Fragments; D012333:RNA, Messenger; D011061:Poly A; D004247:DNA; D007632:Keratan Sulfate; D014357:Trypsin