title: An essential domain of the c-myc protein interacts with a nuclear factor that is also required for E1A-mediated transformation.
abstract: Cell transformation by nuclear oncogenes such as c-myc presumably involves the transcriptional activation of a set of target genes that participate in the control of cell division. The function of a small evolutionarily conserved domain of the c-myc gene encompassing amino acids 129 to 145 was analyzed to explore the relationship between cell transformation and transcriptional activation. Deletion of this domain inactivated the c-myc oncogene for cell transformation while retaining the ability to activate transcription of either myc consensus binding sites or a GAL4-dependent promoter when the c-myc N-terminus was fused to the GAL4 DNA-binding domain. Point mutations that altered a conserved tryptophan (amino acid 136) within this domain had similar effects. Expression of the wt c-Myc N terminus (amino acids 1 to 262) as a GAL4 fusion was a dominant inhibitor of cell transformation by the c-myc oncogene, and this same domain also inhibited transformation by the adenovirus E1A gene. Surprisingly, deletion of amino acids 129 to 145 eliminated the dominant negative activity of GAL4-Myc on both c-myc and E1A transformation. Expression of the GAL4-Myc protein in Cos cells led to the formation of a specific complex between the Myc N terminus and a nuclear factor, and this complex was absent with the dl129-145 mutant. These results suggest that an essential domain of the c-Myc protein interacts with a specific nuclear factor that is also required for E1A transformation.
authors.affiliation: Department of Molecular Biology, Princeton University, New Jersey 08544.
authors.forename: D E
authors.initials: DE
authors.lastname: Brough
authors.forename: T J
authors.initials: TJ
authors.lastname: Hofmann
authors.forename: K B
authors.initials: KB
authors.lastname: Ellwood
authors.forename: R A
authors.initials: RA
authors.lastname: Townley
authors.forename: M D
authors.initials: MD
authors.lastname: Cole
mesh_terms: D017500:Adenovirus E1A Proteins / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D002471:Cell Transformation, Neoplastic; D016384:Consensus Sequence; D004247:DNA / Q000737:chemistry / Q000378:metabolism; D004268:DNA-Binding Proteins; D005656:Fungal Proteins / Q000096:biosynthesis / Q000378:metabolism; D016259:Genes, myc; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000378:metabolism*; D009838:Oligodeoxyribonucleotides; D016271:Proto-Oncogene Proteins c-myc / Q000378:metabolism*; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D014158:Transcription, Genetic; D015533:Transcriptional Activation
chemical_list: D017500:Adenovirus E1A Proteins; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; C052130:GAL4 protein, S cerevisiae; D009687:Nuclear Proteins; D009838:Oligodeoxyribonucleotides; D016271:Proto-Oncogene Proteins c-myc; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D004247:DNA