Transcriptional activation of the tumor necrosis factor alpha-inducible zinc finger protein, A20, is mediated by kappa B elements

J Biol Chem. 1992 Sep 5;267(25):17971-6.


A20 was first identified as a tumor necrosis factor (TNF) primary response transcript encoding a 790-amino acid protein with a unique zinc finger motif. Recently, A20 was shown to protect cells from TNF-induced cytotoxicity in a variety of cell lines. Nuclear run-on studies previously established that TNF activates A20 at the transcriptional level. To further characterize the mechanism by which TNF activates the A20 gene, we have cloned the A20 5'-flanking sequences and identified TNF-responsive elements within the promoter. The transcription initiation site was mapped by both primer extension and S1 nuclease protection experiments to a position 4.2 kilobases (kb) upstream of the initiator methionine; the first and second exon were separated by a 3.9-kb intron. Sequences upstream of the transcription start site were 76% GC-rich and contained six Sp1 binding sites and a TATA-like sequence at -29 but lacked a consensus CCAAT site. Transfection of Jurkat T-cells with an array of A20 promoter CAT constructs showed that two kappa B elements residing at -54 and -66 were required for induction by TNF. Supporting this notion, DNA electrophoretic mobility shift assays using nuclear extracts from unstimulated and TNF-stimulated Jurkat cells demonstrated kappa B-specific binding of a TNF-activated factor to an end-labeled probe containing the two A20 kappa B sequences. Finally, evidence obtained from cotransfection experiments showed that A20 negatively regulated its own expression.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Cell Line
  • DNA-Binding Proteins
  • Endothelium, Vascular / physiology
  • Female
  • Gene Expression Regulation / drug effects
  • Genomic Library
  • Humans
  • Intracellular Signaling Peptides and Proteins
  • Molecular Sequence Data
  • NF-kappa B / metabolism*
  • Nuclear Proteins
  • Oligodeoxyribonucleotides
  • Placenta / physiology
  • Plasmids
  • Poly A / genetics
  • Poly A / isolation & purification
  • Pregnancy
  • Promoter Regions, Genetic*
  • Protein Biosynthesis
  • Proteins / genetics*
  • RNA / genetics
  • RNA / isolation & purification
  • RNA, Messenger
  • Restriction Mapping
  • Transcription, Genetic*
  • Transfection
  • Tumor Necrosis Factor alpha-Induced Protein 3
  • Tumor Necrosis Factor-alpha / pharmacology*
  • Zinc Fingers / genetics*


  • DNA-Binding Proteins
  • Intracellular Signaling Peptides and Proteins
  • NF-kappa B
  • Nuclear Proteins
  • Oligodeoxyribonucleotides
  • Proteins
  • RNA, Messenger
  • Tumor Necrosis Factor-alpha
  • Poly A
  • RNA
  • TNFAIP3 protein, human
  • Tumor Necrosis Factor alpha-Induced Protein 3

Associated data

  • GENBANK/D10341
  • GENBANK/D10342
  • GENBANK/D10343
  • GENBANK/D10344
  • GENBANK/D10345
  • GENBANK/D10346
  • GENBANK/D10347
  • GENBANK/D10348
  • GENBANK/M91590
  • GENBANK/M96756