title: Physical and functional interactions between Drosophila homologue of Swc6/p18Hamlet subunit of the SWR1/SRCAP chromatin-remodeling complex with the DNA repair/transcription factor TFIIH.
abstract: The multisubunit DNA repair and transcription factor TFIIH maintains an intricate cross-talk with different factors to achieve its functions. The p8 subunit of TFIIH maintains the basal levels of the complex by interacting with the p52 subunit. Here, we report that in Drosophila, the homolog of the p8 subunit (Dmp8) is encoded in a bicistronic transcript with the homolog of the Swc6/p18(Hamlet) subunit (Dmp18) of the SWR1/SRCAP chromatin remodeling complex. The SWR1 and SRCAP complexes catalyze the exchange of the canonical histone H2A with the H2AZ histone variant. In eukaryotic cells, bicistronic transcripts are not common, and in some cases, the two encoded proteins are functionally related. We found that Dmp18 physically interacts with the Dmp52 subunit of TFIIH and co-localizes with TFIIH in the chromatin. We also demonstrated that Dmp18 genetically interacts with Dmp8, suggesting that a cross-talk might exist between TFIIH and a component of a chromatin remodeler complex involved in histone exchange. Interestingly, our results also show that when the level of one of the two proteins is decreased and the other maintained, a specific defect in the fly is observed, suggesting that the organization of these two genes in a bicistronic locus has been selected during evolution to allow co-regulation of both genes.
authors.affiliation: Department of Developmental Genetics, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca Morelos, México.
authors.forename: Mariana
authors.initials: M
authors.lastname: Herrera-Cruz
authors.forename: Grisel
authors.initials: G
authors.lastname: Cruz
authors.forename: Viviana
authors.initials: V
authors.lastname: Valadez-Graham
authors.forename: Mariana
authors.initials: M
authors.lastname: Fregoso-Lomas
authors.forename: Claudia
authors.initials: C
authors.lastname: Villicaña
authors.forename: Martha
authors.initials: M
authors.lastname: Vázquez
authors.forename: Enrique
authors.initials: E
authors.lastname: Reynaud
authors.forename: Mario
authors.initials: M
authors.lastname: Zurita
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D030801:Animals, Genetically Modified; D002843:Chromatin / Q000737:chemistry / Q000378:metabolism; D002875:Chromosomes / Q000648:ultrastructure; D003433:Crosses, Genetic; D004260:DNA Repair; D004268:DNA-Binding Proteins / Q000378:metabolism*; D029721:Drosophila Proteins / Q000378:metabolism*; D004331:Drosophila melanogaster; D006657:Histones / Q000737:chemistry; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000378:metabolism*; D010641:Phenotype; D034622:RNA Interference; D012333:RNA, Messenger / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D051758:Transcription Factor TFIIH / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism*; D020798:Two-Hybrid System Techniques
chemical_list: D002843:Chromatin; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; C464822:HAM protein, Drosophila; D006657:Histones; D009687:Nuclear Proteins; D012333:RNA, Messenger; D014157:Transcription Factors; D051758:Transcription Factor TFIIH