Premium
RNA polymerase II 140 wimp mutant and mutations in the TFIIH subunit XPB differentially affect homeotic gene expression in Drosophila
Author(s) -
Gutiérrez Luis,
Merino Carlos,
Vázquez Martha,
Reynaud Enrique,
Zurita Mario
Publication year - 2004
Publication title -
genesis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.093
H-Index - 110
eISSN - 1526-968X
pISSN - 1526-954X
DOI - 10.1002/gene.20066
Subject(s) - homeotic gene , biology , genetics , transcription factor ii h , derepression , ultrabithorax , microbiology and biotechnology , rna polymerase ii holoenzyme , phenotype , gene , promoter , gene expression , psychological repression
Mutations in the XPB and XPD helicases of the DNA repair/transcription factor TFIIH are involved in several human genetic disorders. An unanswered problem concerning the complexity of the phenotype–genotype relationship is why mutations in individual subunits of TFIIH produce specific phenotypes and not many others. In order to investigate this question we tested whether mutations in the Drosophila XPB homolog, haywire (hay ), would modify homeotic derepression phenotypes. In this work, we report that mutations in hay and in the 140‐kDa subunit of the RNA polymerase II ( RpII140 wimp ) act as dominant modifiers of the derepression phenotypes of the Sex combs reduced (Scr) and Ultrabithorax (Ubx) genes. The hay mutations only weakly suppress the Scr derepression phenotype caused by the Antp Scx mutation but not by Polycomb . In contrast, the RpII140 wimp mutation strongly suppresses both Scr derepression phenotypes. In addition, the RpII140 wimp also generates phenotypes indicative of loss of Ubx function. On the other hand, all the derepression homeotic phenotypes are sensitive to the generalized reduction of transcription levels when the flies are grown with actinomycin D. We also show that different promoter control regions have differential sensitivity to different hay alleles. All these results support that although TFIIH is a basal transcription factor, mutations in the subunit encoded by hay have specific effects in the transcription of some genes. genesis 40:58–66, 2004. © 2004 Wiley‐Liss, Inc.