MAZ, a zinc finger protein, binds to c-MYC and C2 gene sequences regulating transcriptional initiation and termination.
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ME1a1, a 16-base-pair nuclear factor binding site residing between the c-MYC P1 and P2 transcription initiation sites, is required for P2 activity. A cDNA encoding a 477-amino acid zinc finger protein designated MAZ (MYC-associated zinc finger protein) was cloned from a HeLa lambda gt11 library by screening with a concatamerized ME1a1 binding site probe. In addition to six potential zinc fingers of the Cys2His2 type, MAZ contains an amino-terminal proline-rich domain and several polyalanine tracts. Its mRNA was present in all human tissues tested except for kidney, as a doublet of approximately 2.5 and 2.7 kilobases, along with differentially expressed minor species. MAZ bound specifically to the wild-type ME1a1 sequence but not to a ME1a1 mutant that also failed to yield P2 activity. When expressed as a fusion protein in a pMAL-c vector, MAZ binds with specificity to a GA box sequence (GGGAGGG) found in the c-MYC P2 promoter, to the P2 attenuator region within the gene's first exon, and to a related sequence involved in the transcriptional termination of the C2 gene. MAZ may encode a transcription factor with dual roles in transcription initiation and termination.
[1] Jonathan D. Licht,et al. Drosophila Krüppel protein is a transcriptional represser , 1990, Nature.
[2] B. McStay,et al. A DNA-binding protein is required for termination of transcription by RNA polymerase I in Xenopus laevis , 1990, Molecular and cellular biology.
[3] C. Asselin,et al. A cis-acting element in the promoter region of the murine c-myc gene is necessary for transcriptional block , 1989, Molecular and cellular biology.