Genomic characterization of human DSPG3

Genome Res. 1999 May;9(5):449-56.

Abstract

DSPG3, the human homolog to chick PG-Lb, is a mejrkp6of the small leucine-rich repeat proteoglycan (SLRP) family, including decorin, biglycan, fibromodulin, and lumican. In contrast to the tissue distribution of the other SLRPs, DSPG3 is predominantly expressed in cartilage. In this study, we have determined that the human DSPG3 gene is composed of seven exons: Exon 2 of DSPG3 includes the start codon, exons 4-7 code for the leucine-rich repeats, exons 3 and 7 contain the potential glycosaminoglycan attachment sites, and exon 7 contains the potential N-glycosylation sites and the stop codon. We have identified two polymorphic variations, an insertion/deletion composed of 19 nucleotides in intron 1 and a tetranucleotide (TATT)n repeat in intron 5. Analysis of 1.6 kb of upstream promoter sequence of DSPG3 reveals three TATA boxes, one of which is 20 nucleotides before the transcription start site. The transcription start site precedes the translation start site by 98 nucleotides. There are 14 potential binding sites for SOX9, a transcription factor present in cartilage, in the promoter, and in the first intron of DSPG3. We have examined the evolution of the SLRP gene family and found that gene products clustered together in the evolutionary tree are encoded by genes with similarities in genomic structure. Hence, it appears that the majority of the introns in the SLRP genes were inserted after the differentiation of the SLRP genes from an ancestral gene that was most likely composed of 2-3 exons.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Cartilage / chemistry
  • Cartilage / metabolism
  • Cattle
  • Chick Embryo
  • Chickens
  • Chondroitin Sulfate Proteoglycans / chemistry
  • Chondroitin Sulfate Proteoglycans / genetics
  • Decorin
  • Evolution, Molecular
  • Exons
  • Extracellular Matrix Proteins
  • Humans
  • Introns
  • Keratan Sulfate / chemistry
  • Keratan Sulfate / genetics
  • Lumican
  • Mice
  • Molecular Sequence Data
  • Multigene Family
  • Promoter Regions, Genetic
  • Proteoglycans / chemistry
  • Proteoglycans / genetics*
  • Sequence Homology, Amino Acid
  • Small Leucine-Rich Proteoglycans

Substances

  • Chondroitin Sulfate Proteoglycans
  • DCN protein, human
  • Dcn protein, mouse
  • Decorin
  • EPYC protein, human
  • Extracellular Matrix Proteins
  • LUM protein, human
  • Lum protein, mouse
  • Lumican
  • Proteoglycans
  • Small Leucine-Rich Proteoglycans
  • Keratan Sulfate

Associated data

  • GENBANK/AF031658
  • GENBANK/U63814