Coordinate expression and distinct DNA-binding characteristics of the four EGR-zinc finger proteins in Jurkat T lymphocytes

Immunobiology. 1997 Dec;198(1-3):179-91. doi: 10.1016/S0171-2985(97)80039-3.


The Early Growth Response Genes (EGR-1 to AT133/EGR-4) encode a family of proteins that are composed of three homologous consecutive zinc fingers of the Cys2-His2 type and different flanking sequence. Upon growth stimulation of resting cells the four EGR-genes are simultaneously transcribed. We have analyzed the expression of the four EGR-proteins in Jurkat T cells and show by Western blot analysis that the four EGR-proteins are coordinately induced upon treatment with a combination of PHA and PMA. As the individual proteins are reported to bind to identical target sequences, we have analyzed the DNA-binding of the native proteins. Using nuclear extract in which we have demonstrated expression of all four EGR-proteins, only EGR-1, but no other member of this protein family is found to bind to the EGR-consensus site (GCG GGG GCG). In addition, DNA-binding of both native EGR-1 and of recombinant EGR-1 and AT133/EGR-4 proteins expressed in insect cells was analyzed. This comparison revealed distinct binding properties of recombinant EGR-1 and AT133/EGR-4 to oligonucleotides that include the EGR-consensus sites. The distinct binding affinities suggest that in vivo EGR-proteins bind to different target sequences and that each EGR-protein regulates distinct target genes. This is underlined by demonstrating that EGR-1 but not AT133/EGR-4 binds to a related G-rich promoter element with the sequence GGG GTG GGG. This G-rich sequence serves as an overlapping binding site for the two zinc finger proteins EGR-1 and Sp1. As similar overlapping binding sites for EGR-1 and Sp1 have been identified in several human and mouse gene promoters, we raise the question whether the Sp1 binding sites described in a large number of eukaryotic gene promoters also represent binding sites for EGR-1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Binding Sites
  • Cell Extracts
  • Cell Line
  • Consensus Sequence
  • DNA-Binding Proteins / biosynthesis
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Early Growth Response Protein 1
  • Early Growth Response Protein 2
  • Early Growth Response Protein 3
  • Early Growth Response Transcription Factors
  • Genes, Overlapping
  • Humans
  • Immediate-Early Proteins*
  • Interleukin-2 / genetics
  • Jurkat Cells
  • Mitogens / pharmacology
  • Oligodeoxyribonucleotides / metabolism*
  • Phytohemagglutinins / pharmacology
  • Promoter Regions, Genetic
  • Recombinant Fusion Proteins / biosynthesis
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Sp1 Transcription Factor / metabolism
  • Spodoptera / cytology
  • Tetradecanoylphorbol Acetate / pharmacology
  • Transcription Factors / biosynthesis
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*
  • Zinc Fingers*


  • Cell Extracts
  • DNA-Binding Proteins
  • EGR1 protein, human
  • EGR2 protein, human
  • EGR4 protein, human
  • Early Growth Response Protein 1
  • Early Growth Response Protein 2
  • Early Growth Response Transcription Factors
  • Egr1 protein, mouse
  • Egr4 protein, mouse
  • Immediate-Early Proteins
  • Interleukin-2
  • Mitogens
  • Oligodeoxyribonucleotides
  • Phytohemagglutinins
  • Recombinant Fusion Proteins
  • Sp1 Transcription Factor
  • Transcription Factors
  • Early Growth Response Protein 3
  • Tetradecanoylphorbol Acetate