Fig 1.
A schematic diagram of comparative genomic organization of mammalian, avian, and fish HEV.
The three open reading frames (ORFs) are labeled and shown as boxes. ORF2 overlaps ORF3, but neither overlaps ORF1. ORF1 encodes nonstructural proteins with the putative functional domains within ORF1 indicated inside the box. ORF2 encodes the capsid protein, and ORF3 encodes a small protein that is involved in virus replication. The genome is capped (m7G Cap) at the 5′ end and contains a poly A tail at the 3′ end. There are noncoding regions (NCR) at the 5′ and 3′ ends of the viral genome. There is a junction region between ORF1 and ORF3 for mammalian and avian HEV, which contains a stem-loop structure and a cis-reactive element (CRE). The avian HEV genome is approximately 600 bp smaller than the mammalian and fish HEV. Hel, helicase; HVR, hypervariable region; MT, methytransferase; NCR, noncoding region; P, a papain-like cysteine protease; RdRp, RNA-dependent RNA polymerase; X, macro domain.
Table 1.
Host range of hepatitis E virus infection and zoonotic risk.