RNAi screen reveals a role for PACSIN2 and caveolins during bacterial cell-to-cell spread

Mol Biol Cell. 2019 Aug 1;30(17):2124-2133. doi: 10.1091/mbc.E19-04-0197. Epub 2019 Jun 26.

Abstract

Listeria monocytogenes is a human bacterial pathogen that disseminates through host tissues using a process called cell-to-cell spread. This critical yet understudied virulence strategy resembles a vesicular form of intercellular trafficking that allows L. monocytogenes to move between host cells without escaping the cell. Interestingly, eukaryotic cells can also directly exchange cellular components via intercellular communication pathways (e.g., trans-endocytosis) using cell-cell adhesion, membrane trafficking, and membrane remodeling proteins. Therefore, we hypothesized that L. monocytogenes would hijack these types of host proteins during spread. Using a focused RNA interference screen, we identified 22 host genes that are important for L. monocytogenes spread. We then found that caveolins (CAV1 and CAV2) and the membrane sculpting F-BAR protein PACSIN2 promote L. monocytogenes protrusion engulfment during spread, and that PACSIN2 specifically localizes to protrusions. Overall, our study demonstrates that host intercellular communication pathways may be coopted during bacterial spread and that specific trafficking and membrane remodeling proteins promote bacterial protrusion resolution.

Publication types

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

MeSH terms

  • A549 Cells
  • Actins / metabolism
  • Adaptor Proteins, Signal Transducing / metabolism*
  • Bacterial Proteins / metabolism
  • Caveolin 1 / metabolism
  • Caveolin 2 / metabolism
  • Caveolins / metabolism*
  • Endocytosis / physiology
  • Eukaryotic Cells / metabolism
  • Host-Pathogen Interactions / physiology
  • Humans
  • Listeria monocytogenes / metabolism
  • Listeria monocytogenes / pathogenicity*
  • Listeriosis / genetics*
  • Listeriosis / metabolism
  • Listeriosis / microbiology*
  • Membrane Proteins / metabolism
  • Protein Transport
  • RNA Interference
  • Virulence

Substances

  • Actins
  • Adaptor Proteins, Signal Transducing
  • Bacterial Proteins
  • CAV1 protein, human
  • CAV2 protein, human
  • Caveolin 1
  • Caveolin 2
  • Caveolins
  • Membrane Proteins
  • PACSIN2 protein, human