Binding of BAZF and Bc16 to STAT6-Binding DNA Sequences

• Published in: Biochemical and biophysical research communications 2001-06, Vol.284 (1), p.26-32
• Main Authors: Hartatik, Tety, Okada, Seiji, Okabe, Shinichiro, Arima, Masafumi, Hatano, Masahiko, Tokuhisa, Takeshi
• Format: Article
• Language: English
• Subjects: Animals; BAZF; BAZF protein; Bc16 protein; Bcl6; Binding, Competitive - drug effects; Binding, Competitive - physiology; Cell Line; consensus binding sequence; Consensus Sequence; DNA - metabolism; DNA-Binding Proteins - genetics; DNA-Binding Proteins - metabolism; GAS motif; Gene Expression; Glutathione Transferase - genetics; Interleukin-4 - metabolism; Mice; Mutagenesis, Site-Directed; Oligonucleotides - genetics; Oligonucleotides - metabolism; Oligonucleotides - pharmacology; Proto-Oncogene Proteins - genetics; Proto-Oncogene Proteins - metabolism; Proto-Oncogene Proteins c-bcl-6; Recombinant Fusion Proteins - genetics; Recombinant Fusion Proteins - metabolism; Regulatory Sequences, Nucleic Acid - physiology; Repressor Proteins - genetics; Repressor Proteins - metabolism; Sequence Analysis, DNA; Signal Transduction - physiology; STAT6; Stat6 protein; STAT6 Transcription Factor; Trans-Activators - metabolism; Transcription Factors - genetics; Transcription Factors - metabolism; transcriptional repressor; Transfection; Zinc Fingers - physiology
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1006/bbrc.2001.4931

BAZF, a family member of Bcl6, can function as a sequence-specific transcriptional repressor. We determined BAZF-binding DNA sequence. The consensus binding sequence (CBS) of BAZF is almost the same as those of Bcl6 previously described. Three nucleotides of T, G and A at position 6, 8, and 9 in the CBS (5′-ATTCCTAGAAAG-3′) are important nucleotides for binding of both BAZF and Bcl6. Since a part (5′-TTC-CTA-GAA-3′) of the CBS resembled the sequence motif (5′-TTC-(N3-4)-GAA-3′) bound by STAT factors, BAZF and Bcl6 can bind to the CD23b-STAT6-binding sequence (5′-TTTC-TTA-GAAAT-3′), the immunoglobulin germline ϵ-STAT6-binding sequence (5′-CTTC-CCAA-GAAC-3′), and the IL4-STAT6-binding sequence (5′-TTTC-CCA-GAAAA-3′) with weak affinity. However, a mutation of C nucleotide to T nucleotide in the IL4-STAT6-binding sequence (5′-TTTC-CTA-GAAAA-3′) strongly increased the binding activity of BAZF and Bcl6. These results suggest that BAZF and Bcl6 can repress some of STAT-induced transcription by binding to DNA sequences recognized by STAT factors.