Sequential CRISPR-Based Screens Identify LITAF and CDIP1 as the Bacillus cereus Hemolysin BL Toxin Host Receptors

Cell Host Microbe. 2020 Sep 9;28(3):402-410.e5. doi: 10.1016/j.chom.2020.05.012. Epub 2020 Jun 15.

Abstract

Bacteria and their toxins are associated with significant human morbidity and mortality. While a few bacterial toxins are well characterized, the mechanism of action for most toxins has not been elucidated, thereby limiting therapeutic advances. One such example is the highly potent pore-forming toxin, hemolysin BL (HBL), produced by the gram-positive pathogen Bacillus cereus. However, how HBL exerts its effects and whether it requires any host factors is unknown. Here, we describe an unbiased genome-wide CRISPR-Cas9 knockout screen that identified LPS-induced TNF-α factor (LITAF) as the HBL receptor. Using LITAF-deficient cells, a second, subsequent whole-genome CRISPR-Cas9 screen identified the LITAF-like protein CDIP1 as a second, alternative receptor. We generated LITAF-deficient mice, which exhibit marked resistance to lethal HBL challenges. This work outlines and validates an approach to use iterative genome-wide CRISPR-Cas9 screens to identify the complement of host factors exploited by bacterial toxins to exert their myriad biological effects.

Keywords: Bacillus cereus; CDIP1; LITAF; bacterial pathogenesis; genome-wide CRISPR screen; hemolysin BL; hemolysis; pore-forming toxin; toxin receptor.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, N.I.H., Intramural

MeSH terms

  • Animals
  • Apoptosis Regulatory Proteins / genetics
  • Apoptosis Regulatory Proteins / physiology*
  • Bacillus cereus / pathogenicity*
  • Bacterial Proteins / physiology*
  • CHO Cells
  • Cell Line
  • Clustered Regularly Interspaced Short Palindromic Repeats
  • Cricetulus
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / physiology*
  • Endothelial Cells
  • Female
  • Gene Knockdown Techniques
  • Genome-Wide Association Study
  • Hemolysin Proteins / physiology*
  • Host-Pathogen Interactions
  • Humans
  • Macrophages
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Receptors, Enterotoxin / genetics
  • Receptors, Enterotoxin / physiology*
  • Transcription Factors / genetics
  • Transcription Factors / physiology*
  • Virulence Factors

Substances

  • Apoptosis Regulatory Proteins
  • Bacterial Proteins
  • CDIP1 protein, mouse
  • DNA-Binding Proteins
  • Hemolysin Proteins
  • Litaf protein, mouse
  • Transcription Factors
  • Virulence Factors
  • hemolysin BL protein, Bacillus
  • Receptors, Enterotoxin