6a5l
From Proteopedia
RNA polymerase II elongation complex stalled at SHL(-1) of the nucleosome, with foreign DNA
Structural highlights
Function[C4QZQ7_KOMPG] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates.[RuleBase:RU363031] [C4R4Y0_KOMPG] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates.[RuleBase:RU004279] [F2QPE6_KOMPC] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates.[PIRNR:PIRNR005586] [H2B1J_HUMAN] Core component of nucleosome. Nucleosomes wrap and compact DNA into chromatin, limiting DNA accessibility to the cellular machineries which require DNA as a template. Histones thereby play a central role in transcription regulation, DNA repair, DNA replication and chromosomal stability. DNA accessibility is regulated via a complex set of post-translational modifications of histones, also called histone code, and nucleosome remodeling.[1] [2] [3] Has broad antibacterial activity. May contribute to the formation of the functional antimicrobial barrier of the colonic epithelium, and to the bactericidal activity of amniotic fluid.[4] [5] [6] Publication Abstract from PubMedGenomic DNA forms chromatin, in which the nucleosome is the repeating unit. The mechanism by which RNA polymerase II (RNAPII) transcribes the nucleosomal DNA remains unclear. Here we report the cryo-electron microscopy structures of RNAPII-nucleosome complexes, in which RNAPII pauses at the superhelical locations, SHL(-6), SHL(-5), SHL(-2), and SHL(-1), of the nucleosome. RNAPII pauses at the major histone-DNA contact sites, and the nucleosome interactions with the RNAPII subunits stabilize the pause. These structures reveal snapshots of nucleosomal transcription, where RNAPII gradually tears DNA from the histone surface, while preserving the histone octamer. Interestingly, the nucleosomes in the SHL(-1) complexes are bound to a "foreign" DNA segment, which might explain the histone transfer mechanism. These results provide the foundations for understanding chromatin transcription and epigenetic regulation. Structural basis of the nucleosome transition during RNA polymerase II passage.,Kujirai T, Ehara H, Fujino Y, Shirouzu M, Sekine SI, Kurumizaka H Science. 2018 Oct 4. pii: science.aau9904. doi: 10.1126/science.aau9904. PMID:30287617[7] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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