The Mad and Myc basic domains are functionally equivalent.

Mikhail A Nikiforov; Nikita Popov; Iulia Kotenko; Marie Henriksson; Michael D Cole

doi:10.1074/jbc.m212298200

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The Mad and Myc basic domains are functionally equivalent.

Mikhail A Nikiforov·Nikita Popov·Iulia Kotenko·Marie Henriksson·Michael D Cole

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Abstract

The Myc/Max/Mad family of transcription factors plays a fundamental role in the regulation of cell proliferation, oncogenic transformation, and cell differentiation. However, it remains unclear whether different heterodimers, such as Myc/Max and Mad/Max, recognize the same or different target genes in vivo. We show by chromatin immunoprecipitation that Myc target genes are also recognized by Mad1 in differentiated HL60 cells. We also substituted the complete basic region of Myc for the corresponding region of Mad. Wild-type c-Myc was then compared with c-Myc(Mad-BR) in oncogenic transformation, regulation of cell proliferation, induction of apoptosis, activation of chromosomal gene expression, and direct binding to chromosomal sites by chromatin immunoprecipitation. We find that the wild-type c-Myc and c-Myc/MadBR proteins have indistinguishable biological activity and target gene recognition in vivo. These data are consistent with a model in which Myc and Mad regulate a common set of target genes.

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Amino Acid Sequence Apoptosis Base Sequence Basic Helix-Loop-Helix Leucine Zipper Transcription Factors DNA Primers DNA-Binding Proteins HL-60 Cells Humans Molecular Sequence Data Protein Binding Proto-Oncogene Proteins c-myc Repressor Proteins Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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Mikhail A Nikiforov, Nikita Popov, Iulia Kotenko, Marie Henriksson, Michael D Cole. 2003-01-21. The Mad and Myc basic domains are functionally equivalent.. https://doi.org/10.1074/jbc.m212298200

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