title: E(y)1/TAF9 mediates the transcriptional output of Notch signaling in Drosophila.
abstract: Transcriptional activation of Notch signaling targets requires the formation of a ternary complex that involves the intracellular domain of the Notch receptor (NICD), DNA-binding protein Suppressor of Hairless [Su(H), RPBJ in mammals] and coactivator Mastermind (Mam). Here, we report that E(y)1/TAF9, a component of the transcription factor TFIID complex, interacts specifically with the NICD-Su(H)-Mam complex to facilitate the transcriptional output of Notch signaling. We identified E(y)1/TAF9 in a large-scale in vivo RNA interference (RNAi) screen for genes that are involved in a Notch-dependent mitotic-to-endocycle transition in Drosophila follicle cells. Knockdown of e(y)1/TAF9 displayed Notch-mutant-like phenotypes and defects in target gene and activity reporter expression in both the follicle cells and wing imaginal discs. Epistatic analyses in these two tissues indicated that E(y)1/TAF9 functions downstream of Notch cleavage. Biochemical studies in S2 cells demonstrated that E(y)1/TAF9 physically interacts with the transcriptional effectors of Notch signaling Su(H) and NICD. Taken together, our data suggest that the association of the NICD-Su(H)-Mastermind complex with E(y)1/TAF9 in response to Notch activation recruits the transcription initiation complex to induce Notch target genes, coupling Notch signaling with the transcription machinery.
authors.affiliation: Department of Biological Science, Florida State University, Tallahassee, FL 32304-4295, USA.
authors.forename: Gengqiang
authors.initials: G
authors.lastname: Xie
authors.affiliation: State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, the Chinese Academy of Sciences, Datun Road 15, Beijing 100101, China.
authors.forename: Zhongsheng
authors.initials: Z
authors.lastname: Yu
authors.affiliation: Department of Biological Science, Florida State University, Tallahassee, FL 32304-4295, USA.
authors.forename: Dongyu
authors.initials: D
authors.lastname: Jia
authors.affiliation: Department of Biological Science, Florida State University, Tallahassee, FL 32304-4295, USA rjiao@sun5.ibp.ac.cn wumin@bio.fsu.edu.
authors.forename: Renjie
authors.initials: R
authors.lastname: Jiao
authors.affiliation: Department of Biological Science, Florida State University, Tallahassee, FL 32304-4295, USA rjiao@sun5.ibp.ac.cn wumin@bio.fsu.edu.
authors.forename: Wu-Min
authors.initials: WM
authors.lastname: Deng
mesh_terms: D000818:Animals; D029721:Drosophila Proteins / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D010641:Phenotype; D051880:Receptors, Notch / Q000378:metabolism*; D015398:Signal Transduction / Q000235:genetics*; D035381:TATA-Binding Protein Associated Factors / Q000378:metabolism*; D035362:Transcription Factor TFIID / Q000378:metabolism*; D014921:Wings, Animal / Q000378:metabolism
chemical_list: D029721:Drosophila Proteins; C497759:N protein, Drosophila; D051880:Receptors, Notch; D035381:TATA-Binding Protein Associated Factors; D035362:Transcription Factor TFIID; C084120:e(y)1 protein, Drosophila
keywords: Drosophila; E(y)1; Notch pathway; TAF9; TFIID complex; Transcriptional regulation