exonuclease activity / endonuclease activity / defense response to virus / RNA binding / ATP binding 類似検索 - 分子機能
: / CRISPR RNA silencing complex Cmr2 subunit, second helical domain / Csm4, C-terminal / CRISPR Csm4 C-terminal domain / CRISPR-associated protein Csm5 / CRISPR-associated protein, Csm2 Type III-A / Csm2 Type III-A / CRISPR-associated RAMP Csm3 / CRISPR type III-associated RAMP protein Csm4 / CRISPR system single-strand-specific deoxyribonuclease Cas10/Csm1 ...: / CRISPR RNA silencing complex Cmr2 subunit, second helical domain / Csm4, C-terminal / CRISPR Csm4 C-terminal domain / CRISPR-associated protein Csm5 / CRISPR-associated protein, Csm2 Type III-A / Csm2 Type III-A / CRISPR-associated RAMP Csm3 / CRISPR type III-associated RAMP protein Csm4 / CRISPR system single-strand-specific deoxyribonuclease Cas10/Csm1 / Csm1, subunit domain B / Csm1 subunit domain B / CRISPR type III-associated protein / RAMP superfamily / GGDEF domain profile. / GGDEF domain / HD domain / HD domain / Reverse transcriptase/Diguanylate cyclase domain 類似検索 - ドメイン・相同性
CRISPR system Cms endoribonuclease Csm3 / CRISPR system single-strand-specific deoxyribonuclease Cas10/Csm1 (subtype III-A) / CRISPR system Cms protein Csm4 / CRISPR system Cms protein Csm2 / CRISPR system Cms protein Csm5 類似検索 - 構成要素
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
R01 GM099604
米国
引用
ジャーナル: Commun Biol / 年: 2022 タイトル: Structural and biochemical characterization of in vivo assembled Lactococcus lactis CRISPR-Csm complex. 著者: Sagar Sridhara / Jay Rai / Charlisa Whyms / Hemant Goswami / Huan He / Walter Woodside / Michael P Terns / Hong Li / 要旨: The small RNA-mediated immunity in bacteria depends on foreign RNA-activated and self RNA-inhibited enzymatic activities. The multi-subunit Type III-A CRISPR-Cas effector complex (Csm) exemplifies ...The small RNA-mediated immunity in bacteria depends on foreign RNA-activated and self RNA-inhibited enzymatic activities. The multi-subunit Type III-A CRISPR-Cas effector complex (Csm) exemplifies this principle and is in addition regulated by cellular metabolites such as divalent metals and ATP. Recognition of the foreign or cognate target RNA (CTR) triggers its single-stranded deoxyribonuclease (DNase) and cyclic oligoadenylate (cOA) synthesis activities. The same activities remain dormant in the presence of the self or non-cognate target RNA (NTR) that differs from CTR only in its 3'-protospacer flanking sequence (3'-PFS). Here we employ electron cryomicroscopy (cryoEM), functional assays, and comparative cross-linking to study in vivo assembled mesophilic Lactococcus lactis Csm (LlCsm) at the three functional states: apo, the CTR- and the NTR-bound. Unlike previously studied Csm complexes, we observed binding of 3'-PFS to Csm in absence of bound ATP and analyzed the structures of the four RNA cleavage sites. Interestingly, comparative crosslinking results indicate a tightening of the Csm3-Csm4 interface as a result of CTR but not NTR binding, reflecting a possible role of protein dynamics change during activation.