EMDB/PDB/SASBDBから引用されている文献のデータベース

キーワード
構造解析手法	All X線回折 NMR 電子顕微鏡小角散乱中性子線回折線維回折粉末回折赤外分光 EPR FRET 理論モデルハイブリッド
著者・登録者
ジャーナル
IF	>30 >20 >10 >5 all

タイトル	Structural visualization of the molecular evolution of CRISPR-Cas9.
ジャーナル・号・ページ	Nat Struct Mol Biol, Vol. 33, Issue 2, Page 304-317, Year 2026
掲載日	2026年1月30日
著者	Naoto Nagahata / Kazuki Kato / Sota Yamada / Soumya Kannan / Sae Okazaki / Yukari Isayama / Masahiro Hiraizumi / Keitaro Yamashita / Eugene V Koonin / Feng Zhang / Hiroshi Nishimasu /
PubMed 要旨	RNA-guided DNA nucleases Cas9 and IscB (insertion sequences Cas9-like OrfB) are components of type II CRISPR-Cas adaptive immune systems and transposon-associated OMEGA (obligate mobile element- ...RNA-guided DNA nucleases Cas9 and IscB (insertion sequences Cas9-like OrfB) are components of type II CRISPR-Cas adaptive immune systems and transposon-associated OMEGA (obligate mobile element-guided activity) systems, respectively. Sequence and structural comparisons indicate that IscB (~500 residues) evolved into Cas9 (~700-1,600 residues) through protein expansion coupled with guide RNA miniaturization. However, the specific sequence of events in this evolutionary transition remains unknown. Here, we report cryo-electron microscopy structures of four phylogenetically diverse RNA-guided nucleases-two IscBs and two Cas9s-each in complex with its cognate guide RNA and target DNA. Comparisons of these four complex structures to previously reported IscB and Cas9 structures indicate that evolution from IscB to Cas9 involved the loss of the N-terminal PLMP domain and the acquisition of the zinc-finger-containing REC3 domain, followed by bridge helix extension and REC1 domain acquisition. These structural changes led to expansion of the REC lobe, increasing the target DNA cleavage specificity. Additionally, the structural conservation of the RNA scaffolds indicates that the dual CRISPR RNA (crRNA) and trans-activating crRNA guides of CRISPR-Cas9 evolved from the single ωRNA guides of OMEGA systems. Our findings provide insights into the succession of structural changes involved in the exaptation of transposon-associated RNA-guided nucleases for the role of effector nucleases in adaptive immune systems.
リンク	Nat Struct Mol Biol / PubMed:41617991
手法	EM (単粒子)
解像度	2.38 - 3.17 Å
構造データ	62001 9k2z EMDB-62001, PDB-9k2z: Cryo-EM structure of the HfmIscB-omega RNA-target DNA complex 手法: EM (単粒子) / 解像度: 2.78 Å 62002 9k30 EMDB-62002, PDB-9k30: Cryo-EM structure of the TbaIscB-omega RNA-target DNA complex 手法: EM (単粒子) / 解像度: 3.17 Å 62003 9k31 EMDB-62003, PDB-9k31: Cryo-EM structure of the YnpsCas9-guide RNA-target DNA complex 手法: EM (単粒子) / 解像度: 2.38 Å 62004 9k32 EMDB-62004, PDB-9k32: Cryo-EM structure of the NbaCas9-guide RNA-target DNA complex 手法: EM (単粒子) / 解像度: 2.85 Å
化合物	ChemComp-MG: Unknown entry ChemComp-HOH: WATER ChemComp-ZN: Unknown entry
由来	metagenome (メタゲノム) synthetic construct (人工物) tissierellia bacterium (バクテリア) nitrospirota bacterium (バクテリア)
キーワード	RNA BINDING PROTEIN / RNA-guided DNA nuclease