Molecular detection of murine noroviruses in laboratory and wild mice

Abstract

Fecal specimens collected from 121 laboratory mice, 30 striped field mice (Apodemus agrarius), 70 yellow-necked mice (Apodemus flavicollis), and 3 bank voles (Myodes glareolus) were tested in sample pools for the presence of murine noroviruses (MNV). Ten of 41 laboratory mice and 2 of 3 striped field mice pooled samples were positive for MNV. All laboratory mouse MNVs were closely related to previously described MNVs. The complete ORF2 (VP1) of both striped field mouse MNVs identified in this study was 1623 nt (541 aa) long and differed at 12% nt (8% aa) positions from each other, at 22-24% nt (15-18% aa) positions from the laboratory mouse MNVs and at 20-22% nt (13-14% aa) positions from the recently described wood mouse (Apodemus sylvaticus) MNVs. This study provides further evidence for the circulation of novel, genetically diverse MNVs in wild mice.

Figure 1

Phylogenetic analysis of 356 nt partial ORF2 sequences of laboratory and wild mouse MNV isolates. The dendrogram was constructed by the UPGMA clustering method of MEGA version 3.1 with Jukes-Cantor distance calculations and 1000 bootstrap analyses. Strains described in this study are in bold.

Figure 2

Phylogenetic analysis of complete VP1 sequences (541 aa) of laboratory and wild mouse MNVs and including Hu/NoV/Farmington Hills/2002/USA (AY502023) as out-group. The dendrogram was constructed by the UPGMA clustering method of MEGA version 3.1 with Poisson correction distance calculations and 1000 bootstrap analyses. Strains described in this study are in bold. WM6 and WM17 represent recently described isolates from house mouse (Smith et al., 2011).