3PJA

Crystal structure of human C3PO complex


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3 Å
  • R-Value Free: 0.254 
  • R-Value Work: 0.206 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structure of C3PO and mechanism of human RISC activation.

Ye, X.Huang, N.Liu, Y.Paroo, Z.Huerta, C.Li, P.Chen, S.Liu, Q.Zhang, H.

(2011) Nat.Struct.Mol.Biol. 18: 650-657

  • DOI: 10.1038/nsmb.2032
  • Primary Citation of Related Structures:  3QB5

  • PubMed Abstract: 
  • Assembly of the RNA-induced silencing complex (RISC) consists of loading duplex (guide-passenger) siRNA onto Argonaute (Ago2) and removing the passenger strand. Ago2 contributes critically to RISC activation by nicking the passenger strand. Here we r ...

    Assembly of the RNA-induced silencing complex (RISC) consists of loading duplex (guide-passenger) siRNA onto Argonaute (Ago2) and removing the passenger strand. Ago2 contributes critically to RISC activation by nicking the passenger strand. Here we reconstituted duplex siRNA-initiated RISC activity using recombinant human Ago2 (hAgo2) and C3PO, indicating that C3PO has a critical role in hAgo2-RISC activation. Consistently, genetic depletion of C3PO compromised RNA silencing in mammalian cells. We determined the crystal structure of hC3PO, which reveals an asymmetric octamer barrel consisting of six translin and two TRAX subunits. This asymmetric assembly is critical for the function of C3PO as an endonuclease that cleaves RNA at the interior surface. The current work supports a Dicer-independent mechanism for human RISC activation, in which Ago2 directly binds duplex siRNA and nicks the passenger strand, and then C3PO activates RISC by degrading the Ago2-nicked passenger strand.


    Organizational Affiliation

    Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Translin
A, B, C, D, E, F, G, H, I
228Homo sapiensGene Names: TSN
EC: 3.1.-.-
Find proteins for Q15631 (Homo sapiens)
Go to Gene View: TSN
Go to UniProtKB:  Q15631
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Translin-associated protein X
J, K, L
290Homo sapiensGene Names: TSNAX (TRAX)
Find proteins for Q99598 (Homo sapiens)
Go to Gene View: TSNAX
Go to UniProtKB:  Q99598
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3 Å
  • R-Value Free: 0.254 
  • R-Value Work: 0.206 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 171.250α = 90.00
b = 95.830β = 104.58
c = 232.885γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data scaling
PHASERphasing
PHENIXrefinement
HKL-2000data reduction
HKL-2000data collection

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2010-11-09 
  • Released Date: 2011-05-11 
  • Deposition Author(s): Huang, N., Zhang, H.

Revision History 

  • Version 1.0: 2011-05-11
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance