Reovirus directly engages integrin to recruit clathrin for entry into host cells

Abstract

Reovirus infection requires the concerted action of viral and host factors to promote cell entry. After interaction of reovirus attachment protein σ1 with cell-surface carbohydrates and proteinaceous receptors, additional host factors mediate virus internalization. In particular, β1 integrin is required for endocytosis of reovirus virions following junctional adhesion molecule A (JAM-A) binding. While integrin-binding motifs in the surface-exposed region of reovirus capsid protein λ2 are thought to mediate integrin interaction, evidence for direct β1 integrin-reovirus interactions and knowledge of how integrins function to mediate reovirus entry is lacking. Here, we use single-virus force spectroscopy and confocal microscopy to discover a direct interaction between reovirus and β1 integrins. Comparison of interactions between reovirus disassembly intermediates as well as mutants and β1 integrin show that λ2 is the integrin ligand. Finally, using fluidic force microscopy, we demonstrate a functional role for β1 integrin interaction in promoting clathrin recruitment to cell-bound reovirus. Our study demonstrates a direct interaction between reovirus and β1 integrins and offers insights into the mechanism of reovirus cell entry. These results provide new perspectives for the development of efficacious antiviral therapeutics and the engineering of improved viral gene delivery and oncolytic vectors.

A CRISPR-Cas9 screen reveals a role for WD repeat-containing protein 81 (WDR81) in the entry of late penetrating viruses

“…As such, a number of proviral host factors have been identified for reovirus. These include cell surface molecules, such as cell surface glycans [ 12 , 13 ], Junctional adhesion molecule A (JAM-A) [ 14 ], Nogo Receptor 1 (NgR1) [ 15 ], and β1 integrin [ 16 , 17 ], that directly engage reovirus particles. The steps following reovirus attachment are also dependent on host factors that deliver reovirus particles to late endosomes [ 18 – 22 ].…”

Cell–Cell Mating Interactions: Overview and Potential of Single-Cell Force Spectroscopy

“…What else lies ahead? Other possibilities offered by AFM force spectroscopy remain to be tapped into; for example, dynamic force spectroscopy can be applied to quantify out-of-equilibrium thermodynamic and kinetic parameters of single-molecular interactions as has been demonstrated for single virus-cell interactions by the Alsteens group [71][72][73][74][75][76][77][78]. This methodology can serve as an excellent platform to investigate the effect of small-molecule inhibitors of adhesive interactions under physiologically relevant conditions.…”

Extending applications of AFM to fluidic AFM in single living cell studies

“…Similarly, any small nonbiological (Aebersold et al, 2015) or biological (Rodrigues, et al, 2018) particles, including EVs (discussed below), viruses, and bacterial pathogens, can be dispensed onto cellular surfaces. In another study, the fluidFM was combined with a fast‐scanning confocal microscope to study host response to viral exposure in real‐time (Koehler et al, 2021). In this work, fluidFM was used to attach nanogold particles (400 nm diameter) functionalized with virions (Koehler et al, 2021).…”

“…In another study, the fluidFM was combined with a fast‐scanning confocal microscope to study host response to viral exposure in real‐time (Koehler et al, 2021). In this work, fluidFM was used to attach nanogold particles (400 nm diameter) functionalized with virions (Koehler et al, 2021).…”