5F9H

Crystal structure of RIG-I helicase-RD in complex with 24-mer 5' triphosphate hairpin RNA

Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.10 Å
  • R-Value Free: 0.266 
  • R-Value Work: 0.213 
  • R-Value Observed: 0.216 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history. 


Literature

Structural basis for m7G recognition and 2'-O-methyl discrimination in capped RNAs by the innate immune receptor RIG-I.

Devarkar, S.C., Wang, C., Miller, M.T., Ramanathan, A., Jiang, F., Khan, A.G., Patel, S.S., Marcotrigiano, J.

(2016) Proc Natl Acad Sci U S A 113: 596-601

  • DOI: 10.1073/pnas.1515152113
  • Primary Citation of Related Structures:  
    5F9F, 5F98, 5F9H

  • PubMed Abstract: 

    • RNAs with 5'-triphosphate (ppp) are detected in the cytoplasm principally by the innate immune receptor Retinoic Acid Inducible Gene-I (RIG-I), whose activation triggers a Type I IFN response. It is thought that self RNAs like mRNAs are not recognized by RIG-I because 5'ppp is capped by the addition of a 7-methyl guanosine (m7G) (Cap-0) and a 2'-O-methyl (2'-OMe) group to the 5'-end nucleotide ribose (Cap-1) ...

    RNAs with 5'-triphosphate (ppp) are detected in the cytoplasm principally by the innate immune receptor Retinoic Acid Inducible Gene-I (RIG-I), whose activation triggers a Type I IFN response. It is thought that self RNAs like mRNAs are not recognized by RIG-I because 5'ppp is capped by the addition of a 7-methyl guanosine (m7G) (Cap-0) and a 2'-O-methyl (2'-OMe) group to the 5'-end nucleotide ribose (Cap-1). Here we provide structural and mechanistic basis for exact roles of capping and 2'-O-methylation in evading RIG-I recognition. Surprisingly, Cap-0 and 5'ppp double-stranded (ds) RNAs bind to RIG-I with nearly identical Kd values and activate RIG-I's ATPase and cellular signaling response to similar extents. On the other hand, Cap-0 and 5'ppp single-stranded RNAs did not bind RIG-I and are signaling inactive. Three crystal structures of RIG-I complexes with dsRNAs bearing 5'OH, 5'ppp, and Cap-0 show that RIG-I can accommodate the m7G cap in a cavity created through conformational changes in the helicase-motif IVa without perturbing the ppp interactions. In contrast, Cap-1 modifications abrogate RIG-I signaling through a mechanism involving the H830 residue, which we show is crucial for discriminating between Cap-0 and Cap-1 RNAs. Furthermore, m7G capping works synergistically with 2'-O-methylation to weaken RNA affinity by 200-fold and lower ATPase activity. Interestingly, a single H830A mutation restores both high-affinity binding and signaling activity with 2'-O-methylated dsRNAs. Our work provides new structural insights into the mechanisms of host and viral immune evasion from RIG-I, explaining the complexity of cap structures over evolution.

    Organizational Affiliation: 

    Center for Advanced Biotechnology and Medicine, Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854 patelss@rutgers.edu jmarco@cabm.rutgers.edu.



Macromolecules

Find similar proteins by: 
(by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Probable ATP-dependent RNA helicase DDX58 A, C, E, G, I, K695Homo sapiensMutation(s): 0 
Gene Names: DDX58
EC: 3.6.4.13
Find proteins for O95786 (Homo sapiens)
Explore O95786 
Go to UniProtKB:  O95786
NIH Common Fund Data Resources
PHAROS:  O95786
GTEx:  ENSG00000107201
Protein Feature View
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  • Reference Sequence
Find similar nucleic acids by: 
(by identity cutoff)  |  Structure
Entity ID: 2
MoleculeChainsLengthOrganismImage
RNA (5'-R(P*AP*AP*UP*AP*UP*AP*AP*UP*AP*GP*UP*GP*AP*UP*AP*UP*UP*AP*UP*AP*UP*UP*C)-3')B, D, F, H, J, L23synthetic construct
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
GTP
Query on GTP
Download Ideal Coordinates CCD File 
B, D, F, H, J, L
GUANOSINE-5'-TRIPHOSPHATE
C10 H16 N5 O14 P3
XKMLYUALXHKNFT-UUOKFMHZSA-N		 Ligand Interaction
ZN
Query on ZN
Download Ideal Coordinates CCD File 
A, C, E, G, I, K
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N		 Ligand Interaction
MG
Query on MG
Download Ideal Coordinates CCD File 
A, E, G, I, K
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N		 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.10 Å
  • R-Value Free: 0.266 
  • R-Value Work: 0.213 
  • R-Value Observed: 0.216 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 111.18α = 90
b = 174.81β = 90
c = 309.28γ = 90
Software Package:
Software NamePurpose
PHENIXrefinement
iMOSFLMdata reduction
Aimlessdata scaling
PHENIXphasing

Structure Validation

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View more in-depth experimental data

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2016-01-13
    Type: Initial release
  • Version 1.1: 2016-01-20
    Changes: Database references, Structure summary
  • Version 1.2: 2016-01-27
    Changes: Database references
  • Version 1.3: 2016-04-06
    Changes: Other