4JM0

Structure of Human Cytomegalovirus Immune Modulator UL141


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.25 Å
  • R-Value Free: 0.279 
  • R-Value Work: 0.201 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

The structure of cytomegalovirus immune modulator UL141 highlights structural Ig-fold versatility for receptor binding.

Nemcovicova, I.Zajonc, D.M.

(2014) Acta Crystallogr.,Sect.D 70: 851-862

  • DOI: 10.1107/S1399004713033750

  • PubMed Abstract: 
  • Natural killer (NK) cells are critical components of the innate immune system as they rapidly detect and destroy infected cells. To avoid immune recognition and to allow long-term persistence in the host, Human cytomegalovirus (HCMV) has evolved a nu ...

    Natural killer (NK) cells are critical components of the innate immune system as they rapidly detect and destroy infected cells. To avoid immune recognition and to allow long-term persistence in the host, Human cytomegalovirus (HCMV) has evolved a number of genes to evade or inhibit immune effector pathways. In particular, UL141 can inhibit cell-surface expression of both the NK cell-activating ligand CD155 as well as the TRAIL death receptors (TRAIL-R1 and TRAIL-R2). The crystal structure of unliganded HCMV UL141 refined to 3.25 Å resolution allowed analysis of its head-to-tail dimerization interface. A `dimerization-deficient' mutant of UL141 (ddUL141) was further designed, which retained the ability to bind to TRAIL-R2 or CD155 while losing the ability to cross-link two receptor monomers. Structural comparison of unliganded UL141 with UL141 bound to TRAIL-R2 further identified a mobile loop that makes intimate contacts with TRAIL-R2 upon receptor engagement. Superposition of the Ig-like domain of UL141 on the CD155 ligand T-cell immunoreceptor with Ig and ITIM domains (TIGIT) revealed that UL141 can potentially engage CD155 similar to TIGIT by using the C'C'' and GF loops. Further mutations in the TIGIT binding site of CD155 (Q63R and F128R) abrogated UL141 binding, suggesting that the Ig-like domain of UL141 is a viral mimic of TIGIT, as it targets the same binding site on CD155 using similar `lock-and-key' interactions. Sequence alignment of the UL141 gene and its orthologues also showed conservation in this highly hydrophobic (L/A)X6G `lock' motif for CD155 binding as well as conservation of the TRAIL-R2 binding patches, suggesting that these host-receptor interactions are evolutionary conserved.


    Organizational Affiliation

    Division of Cell Biology, La Jolla Institute for Allergy and Immunology, 9420 Athena Circle, La Jolla, CA 92037, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Protein UL141
A, B
256Human cytomegalovirus (strain Merlin)Mutation(s): 0 
Gene Names: UL141
Find proteins for Q6RJQ3 (Human cytomegalovirus (strain Merlin))
Go to UniProtKB:  Q6RJQ3
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
NAG
Query on NAG

Download SDF File 
Download CCD File 
A, B
N-ACETYL-D-GLUCOSAMINE
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.25 Å
  • R-Value Free: 0.279 
  • R-Value Work: 0.201 
  • Space Group: P 32 2 1
Unit Cell:
Length (Å)Angle (°)
a = 96.060α = 90.00
b = 96.060β = 90.00
c = 136.071γ = 120.00
Software Package:
Software NamePurpose
REFMACrefinement
Blu-Icedata collection
MOSFLMdata reduction
SCALAdata scaling
PHASERphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2014-02-26
    Type: Initial release
  • Version 1.1: 2014-03-05
    Type: Database references
  • Version 1.2: 2014-08-13
    Type: Database references
  • Version 1.3: 2016-10-19
    Type: Derived calculations