title: The 9aaTAD Is Exclusive Activation Domain in Gal4.
abstract: The Gal4 protein is a well-known prototypic acidic activator that has multiple activation domains. We have previously identified a new activation domain called the nine amino acid transactivation domain (9aaTAD) in Gal4 protein. The family of the 9aaTAD activators currently comprises over 40 members including p53, MLL, E2A and other members of the Gal4 family; Oaf1, Pip2, Pdr1 and Pdr3. In this study, we revised function of all reported Gal4 activation domains. Surprisingly, we found that beside of the activation domain 9aaTAD none of the previously reported activation domains had considerable transactivation potential and were not involved in the activation of transcription. Our results demonstrated that the 9aaTAD domain is the only decisive activation domain in the Gal4 protein. We found that the artificial peptides included in the original Gal4 constructs were results of an unintended consequence of cloning that were responsible for the artificial transcriptional activity. Importantly, the activation domain 9aaTAD, which is the exclusive activation domain in Gal4, is also the central part of a conserved sequence recognized by the inhibitory protein Gal80. We propose a revision of the Gal4 regulation, in which the activation domain 9aaTAD is directly linked to both activation function and Gal80 mediated inhibition.
authors.affiliation: Laboratory of Cancer Biology and Genetics, Department of Pathological Physiology, Masaryk University Brno, Czech Republic.
authors.forename: Martin
authors.initials: M
authors.lastname: Piskacek
authors.affiliation: Laboratory of Cancer Biology and Genetics, Department of Pathological Physiology, Masaryk University Brno, Czech Republic.
authors.forename: Marek
authors.initials: M
authors.lastname: Havelka
authors.affiliation: Laboratory of Cancer Biology and Genetics, Department of Pathological Physiology, Masaryk University Brno, Czech Republic.
authors.forename: Martina
authors.initials: M
authors.lastname: Rezacova
authors.affiliation: Gamma Delta T Cell Laboratory, Department of Pathological Physiology, Faculty of Medicine, Masaryk University Brno, Czech Republic.
authors.forename: Andrea
authors.initials: A
authors.lastname: Knight
mesh_terms: D000595:Amino Acid Sequence; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D000072417:Protein Domains; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation / Q000235:genetics / Q000502:physiology
chemical_list: D004268:DNA-Binding Proteins; C052130:GAL4 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors