National Natural Science Foundation of China (NSFC)
31770948
中国
引用
ジャーナル: PLoS Genet / 年: 2023 タイトル: Structural transitions upon guide RNA binding and their importance in Cas12g-mediated RNA cleavage. 著者: Mengxi Liu / Zekai Li / Jing Chen / Jinying Lin / Qiuhua Lu / Yangmiao Ye / Hongmin Zhang / Bo Zhang / Songying Ouyang / 要旨: Cas12g is an endonuclease belonging to the type V RNA-guided CRISPR-Cas family. It is known for its ability to cleave RNA substrates using a conserved endonuclease active site located in the RuvC ...Cas12g is an endonuclease belonging to the type V RNA-guided CRISPR-Cas family. It is known for its ability to cleave RNA substrates using a conserved endonuclease active site located in the RuvC domain. In this study, we determined the crystal structure of apo-Cas12g, the cryo-EM structure of the Cas12g-sgRNA binary complex and investigated conformational changes that occur during the transition from the apo state to the Cas12g-sgRNA binary complex. The conserved zinc finger motifs in Cas12g undergo an ordered-to-disordered transition from the apo to the sgRNA-bound state and their mutations negatively impact on target RNA cleavage. Moreover, we identified a lid motif in the RuvC domain that undergoes transformation from a helix to loop to regulate the access to the RuvC active site and subsequent cleavage of the RNA substrate. Overall, our study provides valuable insights into the mechanisms by which Cas12g recognizes sgRNA and the conformational changes it undergoes from sgRNA binding to the activation of the RNase active site, thereby laying a foundation for the potential repurposing of Cas12g as a tool for RNA-editing.
プロトコル: SINGLE WAVELENGTH / 単色(M)・ラウエ(L): M / 散乱光タイプ: x-ray
放射波長
波長: 0.9792 Å / 相対比: 1
反射
解像度: 2.24→62.86 Å / Num. obs: 49819 / % possible obs: 99.4 % / 冗長度: 13 % / CC1/2: 0.997 / Rmerge(I) obs: 0.091 / Net I/σ(I): 17
反射 シェル
解像度: 2.24→2.3 Å / Mean I/σ(I) obs: 2.3 / Num. unique obs: 3596 / CC1/2: 0.786 / % possible all: 98.2
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解析
ソフトウェア
名称
バージョン
分類
REFMAC
5.8.0267
精密化
xia2
データ削減
xia2
データスケーリング
PHENIX
1.13-2998
位相決定
精密化
構造決定の手法: 単波長異常分散 / 解像度: 2.24→62.86 Å / Cor.coef. Fo:Fc: 0.948 / Cor.coef. Fo:Fc free: 0.926 / SU B: 7.013 / SU ML: 0.17 / 交差検証法: THROUGHOUT / ESU R: 0.233 / ESU R Free: 0.207 / 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
0.26849
2416
4.9 %
RANDOM
Rwork
0.22398
-
-
-
obs
0.2262
47341
99.32 %
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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