Ubiquitination of Innate Immune Regulator TRAF3 Orchestrates Expulsion of Intracellular Bacteria by Exocyst Complex.

Journal Article

Although the intracellular trafficking system is integral to most physiologic activities, its role in mediating immune responses to infection has remained elusive. Here, we report that infected bladder epithelial cells (BECs) mobilized the exocyst complex, a powerful exporter of subcellular vesicles, to rapidly expel intracellular bacteria back for clearance. Toll-like receptor (TLR) 4 signals emanating from bacteria-containing vesicles (BCVs) were found to trigger K33-linked polyubiquitination of TRAF3 at Lys168, which was then detected by RalGDS, a guanine nucleotide exchange factor (GEF) that precipitated the assembly of the exocyst complex. Although this distinct modification of TRAF3 served to connect innate immune signaling to the cellular trafficking apparatus, it crucially ensured temporal and spatial accuracy in determining which among the many subcellular vesicles was recognized and selected for expulsion in response to innate immune signaling.

Full Text

Duke Authors

Cited Authors

  • Miao, Y; Wu, J; Abraham, SN

Published Date

  • July 2016

Published In

Volume / Issue

  • 45 / 1

Start / End Page

  • 94 - 105

PubMed ID

  • 27438768

Electronic International Standard Serial Number (EISSN)

  • 1097-4180

International Standard Serial Number (ISSN)

  • 1074-7613

Digital Object Identifier (DOI)

  • 10.1016/j.immuni.2016.06.023


  • eng