title: Primary structure of open reading frame 2 and 3 of the hepatitis E virus isolated from Morocco.
abstract: The nucleotide sequence from position 5,014 to 7,186 of the hepatitis E virus (HEV) genome was determined using a set of 10 polymerase chain reaction (PCR) fragments amplified directly from a pool of fecal specimens obtained from patients with well-documented epidemic HEV infection in Morocco. This sequence contains the 3'-terminal region of open reading frame 1 (ORF1), full length ORF2 and ORF3, and a portion of the 3'-noncoding region. The HEV Morocco nucleotide sequence was compared with the corresponding sequences of 13 HEV strains. A region of ORF2 that overlaps with ORF3 was found to be the most conserved region of ORF2, whereas a protein segment encoded by this region was found to be the most variable. Theoretical RNA secondary structure analysis predicted that this region may be folded into a strong secondary structure that may constrain nucleotide sequence variability. In addition, the nucleotide sequence comparison revealed that the HEV Morocco sequence is most homologous to the sequences of the HEV Asian strains compared with the HEV Mexico, swine, and US strains. Phylogenetic analysis performed on the entire ORF2 and ORF3 sequences and on a small fragment of ORF2 allowed classification of the HEV Morocco strain together with a few other known African strains as a separate subtype within the Asian-African genotype.
authors.affiliation: Hepatitis Branch, Division of Viral and Rickettsial Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA.
authors.forename: J
authors.initials: J
authors.lastname: Meng
authors.forename: M
authors.initials: M
authors.lastname: Cong
authors.forename: X
authors.initials: X
authors.lastname: Dai
authors.forename: J
authors.initials: J
authors.lastname: Pillot
authors.forename: M A
authors.initials: MA
authors.lastname: Purdy
authors.forename: H A
authors.initials: HA
authors.lastname: Fields
authors.forename: Y E
authors.initials: YE
authors.lastname: Khudyakov
mesh_terms: D001483:Base Sequence; D002460:Cell Line; D005243:Feces / Q000821:virology; D005814:Genes, Viral / Q000235:genetics; D005838:Genotype; D016751:Hepatitis E / Q000235:genetics / Q000821:virology; D016752:Hepatitis E virus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D006801:Humans; D008969:Molecular Sequence Data; D009018:Morocco; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012367:RNA, Viral / Q000235:genetics / Q000302:isolation & purification; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics*; D015678:Viral Structural Proteins / Q000235:genetics
chemical_list: C400971:ORF2 protein, Hepatitis E virus; C400973:ORF3 protein, Hepatitis E virus; D012367:RNA, Viral; D014764:Viral Proteins; D015678:Viral Structural Proteins