
A dominant-negative mutant of Max that inhibits sequence-specific DNA binding by Myc proteins.
Author(s) -
Marc Billaud,
Kurt J. Isselbacher,
René Bernards
Publication year - 1993
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.90.7.2739
Subject(s) - leucine zipper , mutant , biology , proto oncogene proteins c myc , gene , dna binding protein , dna , microbiology and biotechnology , basic helix loop helix leucine zipper transcription factors , zipper , gene expression , bzip domain , transcription factor , genetics , algorithm , computer science
Myc proteins are basic helix-loop-helix/leucine-zipper proteins that bind to specific DNA sequences. In vivo, Myc proteins have been found associated with Max, another basic helix-loop-helix/leucine-zipper protein. However, it is not known to what extent the dimerization of Myc with Max is required for the manifestation of the Myc-induced phenotype. To investigate this, we constructed a dominant-negative mutant of Max, named dMax, that inhibits sequence-specific DNA binding of Myc proteins. Using a rat neuroblastoma model system, we show that dMax reverts N-Myc-induced changes in cellular gene expression. A control mutant of dMax that contains a proline residue in the leucine-zipper region was unable to bind to N-Myc and did not revert the N-Myc-induced changes in cellular gene expression. These data support the hypothesis that N-Myc affects neuroblastoma gene expression through the formation of a DNA-binding heterodimeric complex with Max in vivo.