4IG8

Structural basis for cytosolic double-stranded RNA surveillance by human OAS1


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.7 Å
  • R-Value Free: 0.283 
  • R-Value Work: 0.229 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural basis for cytosolic double-stranded RNA surveillance by human oligoadenylate synthetase 1.

Donovan, J.Dufner, M.Korennykh, A.

(2013) Proc.Natl.Acad.Sci.USA 110: 1652-1657

  • DOI: 10.1073/pnas.1218528110

  • PubMed Abstract: 
  • The human sensor of double-stranded RNA (dsRNA) oligoadenylate synthetase 1 (hOAS1) polymerizes ATP into 2',5'-linked iso-RNA (2-5A) involved in innate immunity, cell cycle, and differentiation. We report the crystal structure of hOAS1 in complex wit ...

    The human sensor of double-stranded RNA (dsRNA) oligoadenylate synthetase 1 (hOAS1) polymerizes ATP into 2',5'-linked iso-RNA (2-5A) involved in innate immunity, cell cycle, and differentiation. We report the crystal structure of hOAS1 in complex with dsRNA and 2'-deoxy ATP at 2.7 Å resolution, which reveals the mechanism of cytoplasmic dsRNA recognition and activation of oligoadenylate synthetases. Human OAS1 recognizes dsRNA using a previously uncharacterized protein/RNA interface that forms via a conformational change induced by binding of dsRNA. The protein/RNA interface involves two minor grooves and has no sequence-specific contacts, with the exception of a single hydrogen bond between the -NH(2) group of nucleobase G17 and the carbonyl oxygen of serine 56. Using a biochemical readout, we show that hOAS1 undergoes more than 20,000-fold activation upon dsRNA binding and that canonical or GU-wobble substitutions produce dsRNA mutants that retain either full or partial activity, in agreement with the crystal structure. Ultimately, the binding of dsRNA promotes an elaborate conformational rearrangement in the N-terminal lobe of hOAS1, which brings residues D75, D77, and D148 into proximity and creates coordination geometry for binding of two catalytic Mg(2+) ions and ATP. The assembly of this critical active-site structure provides the gate that couples binding of dsRNA to the production and downstream functions of 2-5A.


    Organizational Affiliation

    Department of Molecular Biology, Princeton University, Princeton, NJ 08540, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure


Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
2'-5'-oligoadenylate synthase 1
A
349Homo sapiensGene Names: OAS1 (OIAS)
EC: 2.7.7.84
Find proteins for P00973 (Homo sapiens)
Go to Gene View: OAS1
Go to UniProtKB:  P00973
Entity ID: 2
MoleculeChainsLengthOrganism
RNA (5'-R(*GP*GP*CP*UP*UP*UP*UP*GP*AP*CP*CP*UP*UP*UP*AP*UP*GP*C)-3')B18N/A
Entity ID: 3
MoleculeChainsLengthOrganism
RNA (5'-R(*GP*CP*AP*UP*AP*AP*AP*GP*GP*UP*CP*AP*AP*AP*AP*GP*CP*C)-3')C18N/A
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
DTP
Query on DTP

Download SDF File 
Download CCD File 
A
2'-DEOXYADENOSINE 5'-TRIPHOSPHATE
C10 H16 N5 O12 P3
SUYVUBYJARFZHO-RRKCRQDMSA-N
 Ligand Interaction
MG
Query on MG

Download SDF File 
Download CCD File 
A
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.7 Å
  • R-Value Free: 0.283 
  • R-Value Work: 0.229 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 71.200α = 90.00
b = 93.200β = 90.00
c = 98.600γ = 90.00
Software Package:
Software NamePurpose
XDSdata reduction
PHASERphasing
CBASSdata collection
PHENIXrefinement
XDSdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2013-01-16
    Type: Initial release
  • Version 1.1: 2013-01-30
    Type: Database references
  • Version 1.2: 2013-02-13
    Type: Database references