{"title":"Structural basis of nucleosome transcription mediated by Chd1 and FACT","authors":"L. Farnung, M. Ochmann, M. Engeholm, P. Cramer","doi":"10.1101/2020.11.30.403857","DOIUrl":null,"url":null,"abstract":"Efficient transcription of RNA polymerase II (Pol II) through nucleosomes requires the help of various factors. Here we show biochemically that Pol II transcription through a nucleosome is facilitated by the chromatin remodeler Chd1 and the histone chaperone FACT when the elongation factors Spt4/5 and TFIIS are present. We report cryo-EM structures of transcribing Saccharomyces cerevisiae Pol II−Spt4/5−nucleosome complexes with bound Chd1 or FACT. In the first structure, Pol II transcription exposes the proximal histone H2A−H2B dimer that is bound by Spt5. Pol II has also released the inhibitory DNA-binding region of Chd1 that is poised to pump DNA toward Pol II. In the second structure, Pol II has generated a partially unraveled nucleosome that binds FACT, which excludes Chd1 and Spt5. These results suggest that Pol II progression through a nucleosome activates Chd1, enables FACT binding and eventually triggers transfer of FACT together with histones to upstream DNA. Structural and functional analyses of RNA polymerase II−nucleosome complexes reveal how the chromatin remodeler Chd1 and the histone chaperone FACT mediate Pol II transcription through a nucleosome.","PeriodicalId":18836,"journal":{"name":"Nature Structural &Molecular Biology","volume":null,"pages":null},"PeriodicalIF":16.8000,"publicationDate":"2020-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"55","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Nature Structural &Molecular Biology","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1101/2020.11.30.403857","RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 55
Abstract
Efficient transcription of RNA polymerase II (Pol II) through nucleosomes requires the help of various factors. Here we show biochemically that Pol II transcription through a nucleosome is facilitated by the chromatin remodeler Chd1 and the histone chaperone FACT when the elongation factors Spt4/5 and TFIIS are present. We report cryo-EM structures of transcribing Saccharomyces cerevisiae Pol II−Spt4/5−nucleosome complexes with bound Chd1 or FACT. In the first structure, Pol II transcription exposes the proximal histone H2A−H2B dimer that is bound by Spt5. Pol II has also released the inhibitory DNA-binding region of Chd1 that is poised to pump DNA toward Pol II. In the second structure, Pol II has generated a partially unraveled nucleosome that binds FACT, which excludes Chd1 and Spt5. These results suggest that Pol II progression through a nucleosome activates Chd1, enables FACT binding and eventually triggers transfer of FACT together with histones to upstream DNA. Structural and functional analyses of RNA polymerase II−nucleosome complexes reveal how the chromatin remodeler Chd1 and the histone chaperone FACT mediate Pol II transcription through a nucleosome.
期刊介绍:
Nature Structural & Molecular Biology is a monthly journal that focuses on the functional and mechanistic understanding of how molecular components in a biological process work together. It serves as an integrated forum for structural and molecular studies. The journal places a strong emphasis on the functional and mechanistic understanding of how molecular components in a biological process work together. Some specific areas of interest include the structure and function of proteins, nucleic acids, and other macromolecules, DNA replication, repair and recombination, transcription, regulation of transcription and translation, protein folding, processing and degradation, signal transduction, and intracellular signaling.