N-glycosylation of mouse TRAIL-R and human TRAIL-R1 enhances TRAIL-induced death

Cell Death Differ. 2017 Mar;24(3):500-510. doi: 10.1038/cdd.2016.150. Epub 2017 Feb 10.

Abstract

APO2L/TRAIL (TNF-related apoptosis-inducing ligand) induces death of tumor cells through two agonist receptors, TRAIL-R1 and TRAIL-R2. We demonstrate here that N-linked glycosylation (N-glyc) plays also an important regulatory role for TRAIL-R1-mediated and mouse TRAIL receptor (mTRAIL-R)-mediated apoptosis, but not for TRAIL-R2, which is devoid of N-glycans. Cells expressing N-glyc-defective mutants of TRAIL-R1 and mouse TRAIL-R were less sensitive to TRAIL than their wild-type counterparts. Defective apoptotic signaling by N-glyc-deficient TRAIL receptors was associated with lower TRAIL receptor aggregation and reduced DISC formation, but not with reduced TRAIL-binding affinity. Our results also indicate that TRAIL receptor N-glyc impacts immune evasion strategies. The cytomegalovirus (CMV) UL141 protein, which restricts cell-surface expression of human TRAIL death receptors, binds with significant higher affinity TRAIL-R1 lacking N-glyc, suggesting that this sugar modification may have evolved as a counterstrategy to prevent receptor inhibition by UL141. Altogether our findings demonstrate that N-glyc of TRAIL-R1 promotes TRAIL signaling and restricts virus-mediated inhibition.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Apoptosis / drug effects*
  • Cell Line
  • Cytomegalovirus / metabolism
  • Glycosylation
  • HCT116 Cells
  • Humans
  • Membrane Glycoproteins / genetics
  • Membrane Glycoproteins / metabolism
  • Mice
  • Mutagenesis, Site-Directed
  • Nanoparticles / chemistry
  • Receptors, TNF-Related Apoptosis-Inducing Ligand / deficiency
  • Receptors, TNF-Related Apoptosis-Inducing Ligand / genetics
  • Receptors, TNF-Related Apoptosis-Inducing Ligand / metabolism*
  • Sequence Alignment
  • TNF-Related Apoptosis-Inducing Ligand / toxicity*
  • Tunicamycin / toxicity
  • Viral Proteins / genetics
  • Viral Proteins / metabolism

Substances

  • Membrane Glycoproteins
  • Receptors, TNF-Related Apoptosis-Inducing Ligand
  • TNF-Related Apoptosis-Inducing Ligand
  • UL141 glycoprotein, human cytomegalovirus
  • Viral Proteins
  • Tunicamycin