Frontiers in Immunology (Nov 2020)

IGLR-2, a Leucine-Rich Repeat Domain Containing Protein, Is Required for the Host Defense in Caenorhabditis elegans

  • Cheng-Ju Kuo,
  • Cheng-Ju Kuo,
  • Ya-Chu Hsu,
  • Sin-Tian Wang,
  • Bang-Yu Liou,
  • Serene Boon-Yuean Lim,
  • Yi-Wei Chen,
  • Chang-Shi Chen,
  • Chang-Shi Chen

DOI
https://doi.org/10.3389/fimmu.2020.561337
Journal volume & issue
Vol. 11

Abstract

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Enterohemorrhagic Escherichia coli (EHEC), a human pathogen, also infects Caenorhabditis elegans. We demonstrated previously that C. elegans activates the p38 MAPK innate immune pathway to defend against EHEC infection. However, whether a C. elegans pattern recognition receptor (PRR) exists to regulate the immune pathway remains unknown. PRRs identified in other metazoans contain several conserved domains, including the leucine-rich repeat (LRR). By screening a focused RNAi library, we identified the IGLR-2, a transmembrane protein containing the LRR domain, as a potential immune regulator in C. elegans. Our data showed that iglr-2 regulates the host susceptibility to EHEC infection. Moreover, iglr-2 is required for pathogen avoidance to EHEC. The iglr-2 overexpressed strain, which was more resistant to EHEC originally, showed hypersusceptibility to EHEC upon knockdown of the p38 MAPK pathway. Together, our data suggested that iglr-2 plays an important role in C. elegans to defend EHEC by regulating pathogen-avoidance behavior and the p38 MAPK pathway.

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