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

J Biol Chem. 1993 Jun 5;268(16):11874-80.


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.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Cattle
  • Cells, Cultured
  • Chickens
  • Chondroitin Sulfate Proteoglycans / chemistry
  • Chondroitin Sulfate Proteoglycans / genetics*
  • Cornea / metabolism*
  • DNA / genetics
  • DNA / isolation & purification
  • Gene Library
  • Keratan Sulfate / chemistry
  • Keratan Sulfate / genetics*
  • Lumican
  • Male
  • Molecular Sequence Data
  • Mutagenesis
  • Orchiectomy
  • Peptide Fragments / isolation & purification
  • Plasmids
  • Poly A / genetics
  • Poly A / isolation & purification
  • Protein Structure, Secondary
  • RNA, Messenger / genetics
  • RNA, Messenger / isolation & purification
  • Repetitive Sequences, Nucleic Acid
  • Restriction Mapping
  • Sequence Deletion
  • Sequence Homology, Amino Acid
  • Trypsin


  • Chondroitin Sulfate Proteoglycans
  • Lumican
  • Peptide Fragments
  • RNA, Messenger
  • Poly A
  • DNA
  • Keratan Sulfate
  • Trypsin

Associated data

  • GENBANK/L11063