Open AccessDynamic rotation of the protruding domain enhances the infectivity of norovirus
Author(s) -
Chihong Song,
Reiko TakaiTodaka,
Motohiro Miki,
Kei Haga,
Akira Fujimoto,
Ryoka Ishiyama,
Kazuki Oikawa,
Masahiro Yokoyama,
Naoyuki Miyazaki,
Katsunori Iwasaki,
Kosuke Murakami,
Kazuhiko Katayama,
Kazuyoshi Murata
Publication year - 2020
Publication title -
plos pathogens
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.719
H-Index - 206
eISSN - 1553-7374
pISSN - 1553-7366
DOI - 10.1371/journal.ppat.1008619
Subject(s) - norovirus , capsid , infectivity , biophysics , conformational change , virology , biology , chemistry , microbiology and biotechnology , virus
Norovirus is the major cause of epidemic nonbacterial gastroenteritis worldwide. Lack of structural information on infection and replication mechanisms hampers the development of effective vaccines and remedies. Here, using cryo-electron microscopy, we show that the capsid structure of murine noroviruses changes in response to aqueous conditions. By twisting the flexible hinge connecting two domains, the protruding (P) domain reversibly rises off the shell (S) domain in solutions of higher pH, but rests on the S domain in solutions of lower pH. Metal ions help to stabilize the resting conformation in this process. Furthermore, in the resting conformation, the cellular receptor CD300lf is readily accessible, and thus infection efficiency is significantly enhanced. Two similar P domain conformations were also found simultaneously in the human norovirus GII.3 capsid, although the mechanism of the conformational change is not yet clear. These results provide new insights into the mechanisms of non-enveloped norovirus transmission that invades host cells, replicates, and sometimes escapes the hosts immune system, through dramatic environmental changes in the gastrointestinal tract.