title: Nucleosomal Barrier to Transcription: Structural Determinants and Changes in Chromatin Structure.
abstract: Packaging of DNA into chromatin affects all processes on DNA. Nucleosomes present a strong barrier to transcription, raising important questions about the nature and the mechanisms of overcoming the barrier. Recently it was shown that DNA sequence, DNA-histone interactions and backtracking by RNA polymerase II (Pol II) all contribute to formation of the barrier. After partial uncoiling of nucleosomal DNA from histone octamer by Pol II and backtracking of the enzyme, nucleosomal DNA recoils on the octamer, locking Pol II in the arrested state. Histone chaperones and transcription factors TFIIS, TFIIF and FACT facilitate transcription through chromatin using different molecular mechanisms.
authors.affiliation: Cancer Epigenetics Program, Fox Chase Cancer Center, Philadelphia, PA 19111; Biology Faculty, Lomonosov Moscow State University, Moscow, Russia.
authors.forename: Vasily M
authors.initials: VM
authors.lastname: Studitsky
authors.affiliation: Cancer Epigenetics Program, Fox Chase Cancer Center, Philadelphia, PA 19111.
authors.forename: Ekaterina V
authors.initials: EV
authors.lastname: Nizovtseva
authors.affiliation: Biology Faculty, Lomonosov Moscow State University, Moscow, Russia.
authors.forename: Alexey K
authors.initials: AK
authors.lastname: Shaytan
authors.affiliation: Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA.
authors.forename: Donal S
authors.initials: DS
authors.lastname: Luse
keywords: RNA polymerase II; arrest; chromatin; elongation; intermediates; mechanism; nucleosome; pausing; structure; transcription