4OUL

Crystal structure of human Caprin-2 C1q domain


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.949 Å
  • R-Value Free: 0.251 
  • R-Value Work: 0.203 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structural insights into the C1q domain of Caprin-2 in canonical Wnt signaling

Miao, H.Jia, Y.Xie, S.Wang, X.Zhao, J.Chu, Y.Zhou, Z.Shi, Z.Song, X.Li, L.

(2014) J.Biol.Chem. 289: 34104-34113

  • DOI: 10.1074/jbc.M114.591636
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Previously, we have identified Caprin-2 as a new regulator in canonical Wnt signaling through a mechanism of facilitating LRP5/6 phosphorylation; moreover, we found that its C-terminal C1q-related domain (Cap2_CRD) is required for this process. Here, ...

    Previously, we have identified Caprin-2 as a new regulator in canonical Wnt signaling through a mechanism of facilitating LRP5/6 phosphorylation; moreover, we found that its C-terminal C1q-related domain (Cap2_CRD) is required for this process. Here, we determined the crystal structures of Cap2_CRD from human and zebrafish, which both associate as a homotrimer with calcium located at the symmetric center. Surprisingly, the calcium binding-deficient mutant exists as a more stable trimer than its wild-type counterpart. Further studies showed that this Caprin-2 mutant disabled in binding calcium maintains the activity of promoting LRP5/6 phosphorylation, whereas the mutations disrupting Cap2_CRD homotrimer did impair such activity. Together, our findings suggested that the C-terminal CRD domain of Caprin-2 forms a flexible homotrimer mediated by calcium and that such trimeric assembly is required for Caprin-2 to regulate canonical Wnt signaling.


    Organizational Affiliation

    From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Caprin-2
A, B, C, D, E, F
140Homo sapiensMutation(s): 0 
Gene Names: CAPRIN2 (C1QDC1, EEG1, KIAA1873, RNG140)
Find proteins for Q6IMN6 (Homo sapiens)
Go to Gene View: CAPRIN2
Go to UniProtKB:  Q6IMN6
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
GOL
Query on GOL

Download SDF File 
Download CCD File 
D
GLYCEROL
GLYCERIN; PROPANE-1,2,3-TRIOL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
CA
Query on CA

Download SDF File 
Download CCD File 
A, B, D, E
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.949 Å
  • R-Value Free: 0.251 
  • R-Value Work: 0.203 
  • Space Group: P 1
Unit Cell:
Length (Å)Angle (°)
a = 48.353α = 89.51
b = 48.342β = 87.24
c = 80.884γ = 71.74
Software Package:
Software NamePurpose
HKL-2000data scaling
PHASERphasing
PHENIXrefinement
HKL-2000data collection
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2014-02-17 
  • Released Date: 2014-10-29 
  • Deposition Author(s): Song, X., Li, L.

Revision History 

  • Version 1.0: 2014-10-29
    Type: Initial release
  • Version 1.1: 2015-04-08
    Type: Database references