Analysis of the promoter and transcription start sites of the human thrombospondin 2 gene (THBS2)

Gene. 1997 Jul 1;193(1):5-11. doi: 10.1016/s0378-1119(97)00070-x.

Abstract

To identify features of the human thrombospondin 2 gene (THBS2) important for regulation of expression, the sequences of 5 kb of the promoter/5' flank and 3 kb of transcribed and intronic DNA were determined. Two repetitive sequences were found: an MLT1c element located 2.2 kb 5' of exon 1 and, further 5', 1.8 kb of a Tigger1 element. Putative transcription factor binding sites that might be significant for THBS2 regulation included p53, NF-kappaB, Spl, Myc-CF1, NF-Y, CF1, AP1, and GATA sites. Alignment of the promoter/5' flank sequence with the mouse Thbs2 promoter revealed 78% identity for a 450 bp region immediately upstream from the mouse transcription start site. No significant homology was detected between the human thrombospondin 2 and thrombospondin 1 promoters. Comparison of the THBS2 genomic and cDNA sequences revealed that, in contrast to Thbs2, exon 1 is divided into exons 1A and 1B by a small (93 bp) intron. The transcription start site was investigated by a PCR procedure and by 5' RACE, and yielded a size for exon 1A of at least 186 bp. Tissue-specific differences in transcription start sites were found, with transcript lengths in the order: fetal lung > adult lung > fetal brain. These results suggest that tissue-specific differences in expression of the THBS2 gene may be determined, in part, by selection of the transcription start site and resulting differences in the 5' untranslated region.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Binding Sites
  • Consensus Sequence
  • Conserved Sequence
  • Exons
  • Gene Expression Regulation*
  • Genomic Library
  • Humans
  • Introns
  • Membrane Glycoproteins / genetics*
  • Mice
  • Molecular Sequence Data
  • Polymerase Chain Reaction
  • Promoter Regions, Genetic*
  • Protein Binding
  • Sequence Analysis, DNA
  • Thrombospondins
  • Transcription Factors / metabolism
  • Transcription, Genetic

Substances

  • Membrane Glycoproteins
  • Thrombospondins
  • Transcription Factors

Associated data

  • GENBANK/U79410