本帖最后由 细胞海洋 于 2012-11-9 14:33 编辑 ! |) ~2 A7 P3 w& \3 g) H! r
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9 November, 2012 Volume 151, Issue 4/ i# K" {6 }) G, H1 Q/ a) Q' m2 ?
On the cover: Nucleosomes serve as roadblocks to transcription, and in this issue, Bintu et al. (pp. 738–749) dissect these imposed barriers to rapid passage by eukaryotic RNA polymerase II (Pol II). Using single-molecule methods, they determine how the individual elements of the nucleosome—the histone tails, the specific histone-DNA contacts, and the DNA sequence—modulate the dynamics of transcription. The clay model on the cover illustrates how Pol II has to overcome two types of barriers during transcription through a nucleosome (blue): the histone tails at the entry site of the nucleosome (horizontal gate) and the histone-DNA contacts at the nucleosome dyad (stop sign). The secondary structure of the nascent RNA (pink) restricts backward movements of the polymerase during pauses, aiding transcription. Conceptual design by Lacramioara Bintu and Manchuta Dangkulwanich. Artwork by Manchuta Dangkulwanich and Gheorghe Chistol.( x# A7 `8 m# Y3 K! I5 V
9 u& J4 y: ? t$ c# W 作者: 86964109 时间: 2012-11-9 15:00
