Forgot Password

If you have forgotten your password you can enter your email here and get a temporary password sent to your email.

IκB kinase ε-dependent phosphorylation and degradation of X-linked inhibitor of apoptosis sensitizes cells to virus-induced apoptosis.

X-linked inhibitor of apoptosis (XIAP) is a potent antagonist of caspase 3-, 7-, and 9-dependent apoptotic activities that functions as an E3 ubiquitin ligase, and it targets caspases for degradation. In this study, we demonstrate that Sendai virus (SeV) infection results in the IKKε- or TBK1-mediated phosphorylation of XIAP in vivo at Ser430, resulting in Lys(48)-linked autoubiquitination at Lys322/328 residues, followed by the subsequent proteasomal degradation of XIAP. Interestingly, IKKε expression and XIAP turnover increases SeV-triggered mitochondrion-dependent apoptosis via the release of caspase 3, whereas TBK1 expression does not increase apoptosis. Interestingly, phosphorylation also regulates XIAP interaction with the transcription factor IRF3, suggesting a role in IRF3-Bax-mediated apoptosis. Our findings reveal a novel function of IKKε as a regulator of the virus-induced triggering of apoptosis via the phosphorylation-dependent turnover of XIAP.

Pubmed ID: 22072751


  • Nakhaei P
  • Sun Q
  • Solis M
  • Mesplede T
  • Bonneil E
  • Paz S
  • Lin R
  • Hiscott J


Journal of virology

Publication Data

January 29, 2012

Associated Grants

  • Agency: Canadian Institutes of Health Research, Id:

Mesh Terms

  • Amino Acid Motifs
  • Apoptosis
  • Cell Line
  • Humans
  • I-kappa B Kinase
  • Phosphorylation
  • Respirovirus Infections
  • Sendai virus
  • X-Linked Inhibitor of Apoptosis Protein