5LDE

Crystal structure of a vFLIP-IKKgamma stapled peptide dimer


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.38 Å
  • R-Value Free: 0.290 
  • R-Value Work: 0.255 

wwPDB Validation 3D Report Full Report


This is version 2.0 of the entry. See complete history

Literature

IKK gamma-Mimetic Peptides Block the Resistance to Apoptosis Associated with Kaposi's Sarcoma-Associated Herpesvirus Infection.

Briggs, L.C.Chan, A.W.E.Davis, C.A.Whitelock, N.Hotiana, H.A.Baratchian, M.Bagneris, C.Selwood, D.L.Collins, M.K.Barrett, T.E.

(2017) J. Virol. 91: --

  • DOI: 10.1128/JVI.01170-17

  • PubMed Abstract: 
  • Primary effusion lymphoma (PEL) is a lymphogenic disorder associated with Kaposi's sarcoma-associated herpesvirus (KSHV) infection. Key to the survival and proliferation of PEL is the canonical NF-κB pathway, which becomes constitutively activated fo ...

    Primary effusion lymphoma (PEL) is a lymphogenic disorder associated with Kaposi's sarcoma-associated herpesvirus (KSHV) infection. Key to the survival and proliferation of PEL is the canonical NF-κB pathway, which becomes constitutively activated following overexpression of the viral oncoprotein KSHV vFLIP (ks-vFLIP). This arises from its capacity to form a complex with the modulatory subunit of the IκB kinase (IKK) kinase, IKKγ (or NEMO), resulting in the overproduction of proteins that promote cellular survival and prevent apoptosis, both of which are important drivers of tumorigenesis. Using a combination of cell-based and biophysical assays together with structural techniques, we showed that the observed resistance to cell death is largely independent of autophagy or major death receptor signaling pathways and demonstrated that direct targeting of the ks-vFLIP-IKKγ interaction both in cells and in vitro can be achieved using IKKγ-mimetic peptides. Our results further reveal that these peptides not only induce cell killing but also potently sensitize PEL to the proapoptotic agents tumor necrosis factor alpha and etoposide and are the first to confirm ks-vFLIP as a tractable target for the treatment of PEL and related disorders.IMPORTANCE KSHV vFLIP (ks-vFLIP) has been shown to have a crucial role in cellular transformation, in which it is vital for the survival and proliferation of primary effusion lymphoma (PEL), an aggressive malignancy associated with infection that is resistant to the majority of chemotherapeutic drugs. It operates via subversion of the canonical NF-κB pathway, which requires a physical interaction between ks-vFLIP and the IKK kinase modulatory subunit IKKγ. While this interaction has been directly linked to protection against apoptosis, it is unclear whether the suppression of other cell death pathways implicated in ks-vFLIP pathogenesis is an additional contributor. We demonstrate that the interaction between ks-vFLIP and IKKγ is pivotal in conferring resistance to apoptosis. Additionally, we show that the ks-vFLIP-IKKγ complex can be disrupted using peptides leading to direct killing and the sensitization of PEL cells to proapoptotic agents. Our studies thus provide a framework for future therapeutic interventions.


    Organizational Affiliation

    Institute for Structural and Molecular Biology, Department of Biological Sciences, Birkbeck College, London, United Kingdom.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Immunoglobulin G-binding protein G,Viral FLICE protein
A, B
265Streptococcus sp. group GHuman herpesvirus 8 type P (isolate GK18)
This entity is chimeric
Mutation(s): 0 
Gene Names: spg, ORF71
Find proteins for P19909 (Streptococcus sp. group G)
Go to UniProtKB:  P19909
Find proteins for F5HEZ4 (Human herpesvirus 8 type P (isolate GK18))
Go to UniProtKB:  F5HEZ4
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Inhibitor of kappa light polypeptide gene enhancer in B-cells, kinase gamma, isoform CRA_a
R, S
20Homo sapiensMutation(s): 3 
Gene Names: IKBKG (FIP3, NEMO)
Find proteins for Q9Y6K9 (Homo sapiens)
Go to Gene View: IKBKG
Go to UniProtKB:  Q9Y6K9
Small Molecules
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
6ZS
Query on 6ZS
R, S
L-peptide linkingC5 H11 N O2

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Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.38 Å
  • R-Value Free: 0.290 
  • R-Value Work: 0.255 
  • Space Group: P 63
Unit Cell:
Length (Å)Angle (°)
a = 90.510α = 90.00
b = 90.510β = 90.00
c = 134.780γ = 120.00
Software Package:
Software NamePurpose
PHASERphasing
BUSTERrefinement
Aimlessdata scaling
XDSdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data

  • Deposited Date: 2016-06-24 
  • Released Date: 2017-10-04 
  • Deposition Author(s): Barrett, T.

Funding OrganizationLocationGrant Number
Cancer Research UKUnited KingdomC19746/A9867

Revision History 

  • Version 1.0: 2017-10-04
    Type: Initial release
  • Version 2.0: 2017-11-22
    Type: Advisory, Atomic model, Database references, Structure summary