PDBsum entry 4rdp

RNA binding protein

PDB id: 4rdp

Contents

Protein chains

250 a.a.

PDB id:

4rdp

Name:

RNA binding protein

Title:

Crystal structure of cmr4

Structure:

Crispr system cmr subunit cmr4. Chain: a, b. Synonym: crispr type iii-b/ramp module ramp protein cmr4. Engineered: yes

Source:

Pyrococcus furiosus. Organism_taxid: 2261. Gene: cmr4. Expressed in: escherichia coli. Expression_system_taxid: 562

Resolution:

2.85Å R-factor: 0.185 R-free: 0.235

Authors:

Y.Shao,L.Tang,H.Li

Key ref:

N.F.Ramia et al. (2014). Essential structural and functional roles of the Cmr4 subunit in RNA cleavage by the Cmr CRISPR-Cas complex. Cell Rep, 9, 1610-1617. PubMed id: 25482566 DOI: 10.1016/j.celrep.2014.11.007

Date:

19-Sep-14 Release date: 24-Dec-14

Protein chains

Q8U1S9  (CMR4_PYRFU) -  CRISPR system Cmr endoribonuclease Cmr4 from Pyrococcus furiosus (strain ATCC 43587 / DSM 3638 / JCM 8422 / Vc1)

Seq: 295 a.a.

Struc: 250 a.a.

Enzyme reactions

• Enzyme class: E.C.3.1.-.-

DOI no: 10.1016/j.celrep.2014.11.007

Cell Rep 9:1610-1617 (2014)

PubMed id: 25482566

Essential structural and functional roles of the Cmr4 subunit in RNA cleavage by the Cmr CRISPR-Cas complex.

N.F.Ramia, M.Spilman, L.Tang, Y.Shao, J.Elmore, C.Hale, A.Cocozaki, N.Bhattacharya, R.M.Terns, M.P.Terns, H.Li, S.M.Stagg.

ABSTRACT

The Cmr complex is the multisubunit effector complex of the type III-B clustered regularly interspaced short palindromic repeats (CRISPR)-Cas immune system. The Cmr complex recognizes a target RNA through base pairing with the integral CRISPR RNA (crRNA) and cleaves the target at multiple regularly spaced locations within the complementary region. To understand the molecular basis of the function of this complex, we have assembled information from electron microscopic and X-ray crystallographic structural studies and mutagenesis of a complete Pyrococcus furiosus Cmr complex. Our findings reveal that four helically packed Cmr4 subunits, which make up the backbone of the Cmr complex, act as a platform to support crRNA binding and target RNA cleavage. Interestingly, we found a hook-like structural feature associated with Cmr4 that is likely the site of target RNA binding and cleavage. Our results also elucidate analogies in the mechanisms of crRNA and target molecule binding by the distinct Cmr type III-A and Cascade type I-E complexes.