ジャーナル: Structure / 年: 2015 タイトル: Molecular basis of histone tail recognition by human TIP5 PHD finger and bromodomain of the chromatin remodeling complex NoRC. 著者: Cynthia Tallant / Erica Valentini / Oleg Fedorov / Lois Overvoorde / Fleur M Ferguson / Panagis Filippakopoulos / Dmitri I Svergun / Stefan Knapp / Alessio Ciulli / 要旨: Binding of the chromatin remodeling complex NoRC to RNA complementary to the rDNA promoter mediates transcriptional repression. TIP5, the largest subunit of NoRC, is involved in recruitment to rDNA ...Binding of the chromatin remodeling complex NoRC to RNA complementary to the rDNA promoter mediates transcriptional repression. TIP5, the largest subunit of NoRC, is involved in recruitment to rDNA by interactions with promoter-bound TTF-I, pRNA, and acetylation of H4K16. TIP5 domains that recognize posttranslational modifications on histones are essential for recruitment of NoRC to chromatin, but how these reader modules recognize site-specific histone tails has remained elusive. Here, we report crystal structures of PHD zinc finger and bromodomains from human TIP5 and BAZ2B in free form and bound to H3 and/or H4 histones. PHD finger functions as an independent structural module in recognizing unmodified H3 histone tails, and the bromodomain prefers H3 and H4 acetylation marks followed by a key basic residue, KacXXR. Further low-resolution analyses of PHD-bromodomain modules provide molecular insights into their trans histone tail recognition, required for nucleosome recruitment and transcriptional repression of the NoRC complex.
解像度: 1.65→64.87 Å / Cor.coef. Fo:Fc: 0.959 / Cor.coef. Fo:Fc free: 0.952 / SU B: 2.974 / SU ML: 0.057 / 交差検証法: THROUGHOUT / σ(F): 0 / ESU R: 0.092 / ESU R Free: 0.088 / 立体化学のターゲット値: MAXIMUM LIKELIHOOD / 詳細: HYDROGENS HAVE BEEN ADDED IN THE RIDING POSITIONS
Rfactor
反射数
%反射
Selection details
Rfree
0.20495
1661
4.7 %
RANDOM
Rwork
0.18534
-
-
-
obs
0.18631
33458
98.22 %
-
all
-
35633
-
-
溶媒の処理
イオンプローブ半径: 0.8 Å / 減衰半径: 0.8 Å / VDWプローブ半径: 1.2 Å / 溶媒モデル: MASK