2. Academic Validation
  3. Genome-Wide CRISPR Screen Identifies Semaphorin 6A and 6B as Receptors for Paeniclostridium sordellii Toxin TcsL

Genome-Wide CRISPR Screen Identifies Semaphorin 6A and 6B as Receptors for Paeniclostridium sordellii Toxin TcsL

  • Cell Host Microbe. 2020 May 13;27(5):782-792.e7. doi: 10.1016/j.chom.2020.03.007.
Songhai Tian 1,  Yang Liu 2,  Hao Wu 3,  Hao Liu 1,  Ji Zeng 1,  Mei Yuk Choi 4,  Hong Chen 3,  Ralf Gerhard 5,  Min Dong 6
Affiliations

Affiliations

  • 1 Department of Urology, Boston Children's Hospital, Boston, MA 02115, USA; Department of Surgery and Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA.
  • 2 Department of Urology, Boston Children's Hospital, Boston, MA 02115, USA; Department of Surgery and Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA; Department of Nephrology, The First Hospital of Jilin University, Changchun 130012, China.
  • 3 The Vascular Biology Program, Department of Surgery, Boston Children's Hospital and Harvard Medical School, MA 02115, USA.
  • 4 Division of Genetics, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
  • 5 Institute of Toxicology, Hannover Medical School, Hannover, 30625, Germany.
  • 6 Department of Urology, Boston Children's Hospital, Boston, MA 02115, USA; Department of Surgery and Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA. Electronic address: min.dong@childrens.harvard.edu.
PMID: 32302524 DOI: 10.1016/j.chom.2020.03.007
Abstract

The exotoxin TcsL is a major virulence factor in Paeniclostridium (Clostridium) sordellii and responsible for the high lethality rate associated with P. sordellii Infection. Here, we present a genome-wide CRISPR-Cas9-mediated screen using a human lung carcinoma cell line and identify semaphorin (SEMA) 6A and 6B as receptors for TcsL. Disrupting SEMA6A/6B expression in several distinct human cell lines and primary human endothelial cells results in reduced TcsL sensitivity, while SEMA6A/6B over-expression increases their sensitivity. TcsL recognizes the extracellular domain (ECD) of SEMA6A/6B via a region homologous to the receptor-binding site in Clostridioides difficile toxin B (TcdB), which binds the human receptor Frizzled. Exchanging the receptor-binding interfaces between TcsL and TcdB switches their receptor-binding specificity. Finally, administration of SEMA6A-ECD proteins protects human cells from TcsL toxicity and reduces TcsL-induced damage to lung tissues and the lethality rate in mice. These findings establish SEMA6A and 6B as pathophysiologically relevant receptors for TcsL.

Keywords

CRISPR screen; Clostridium sordellii; Paeniclostridium sordellii; TcsL; bacterial toxin; large clostridial toxin; semaphorin; semaphorin 6,Clostridium difficile.

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