A 3' transcriptional enhancer regulates tissue-specific expression of the human CD2 gene

EMBO J. 1990 Oct;9(10):3129-36.

Abstract

A strong lymphocyte-specific transcriptional enhancer was identified within a DNase I hypersensitive site at the 3' end of the human CD2 gene. Full activity, in a transient expression assay, was contained within a region of 550 bp (minimal enhancer). T cells which express CD2 could use the enhancer to activate transcription from the reporter gene chloramphenicol acetyltransferase in the context of a heterologous promoter. Lower levels of transcription were detected in non-CD2-expressing T cells and in B cells. In contrast, the enhancer did not function in the epithelial cell line HeLa or in Colo 320 HSR, a cell line of neuroendocrine origin. Low levels of enhancement were detectable from two core regions, which acted synergistically with other cis-acting sequences to generate the complete enhancer. DNase I footprinting studies identified six cis-acting sequences to which proteins bound. Five of these sequence motifs were novel; the sixth was a canonical cAMP response element. Topoisomerase II, and scaffold attachment region consensus sequences were also found within an A/T-rich area downstream of the minimal enhancer. Neither region was bound to the nuclear matrix. The CD2 enhancer is modular in structure, it is constructed of novel cis-acting sequences and it is a major component of the regulatory system that controls expression of the CD2 gene.

MeSH terms

  • Base Sequence
  • Cell Nucleus / metabolism
  • Chloramphenicol O-Acetyltransferase / genetics
  • Chloramphenicol O-Acetyltransferase / metabolism
  • DNA Probes
  • Deoxyribonuclease I
  • Enhancer Elements, Genetic*
  • Gene Expression Regulation*
  • Humans
  • Molecular Sequence Data
  • Recombinant Fusion Proteins / metabolism
  • Restriction Mapping
  • Transcription, Genetic*
  • Transfection

Substances

  • DNA Probes
  • Recombinant Fusion Proteins
  • Chloramphenicol O-Acetyltransferase
  • Deoxyribonuclease I