title: Molecular characterisation of the NSP4 gene of group A human rotavirus G2P[4] strains circulating in São Paulo, Brazil, from 1994 and 2006 to 2010.
abstract: Group A human rotaviruses (HuRVA) are causative agents of acute gastroenteritis. Six viral structural proteins (VPs) and six nonstructural proteins (NSPs) are produced in RV-infected cells. NSP4 is a diarrhoea-inducing viral enterotoxin and NSP4 gene analysis revealed at least 15 (E1-E15) genotypes. This study analysed the NSP4 genetic diversity of HuRVA G2P[4] strains collected in the state of São Paulo (SP) from 1994 and 2006-2010 using reverse transcription-polymerase chain reaction, sequencing and phylogenetic analysis. Forty (97.6%) G2P[4] strains displayed genotype E2; one strain (2.4%) displayed genotype E1. These results are consistent with the proposed linkage between VP4/VP7 (G2P[4]) and the NSP4 (E2) genotype of HuRVA. NSP4 phylogenetic analysis showed distinct clusters, with grouping of most strains by their genotype and collection year, and most strains from SP were clustered together with strains from other Brazilian states. A deduced amino acid sequence alignment for E2 showed many variations in the C-terminal region, including the VP4-binding domain. Considering the ability of NSP4 to generate host immunity, monitoring NSP4 variations, along with those in the VP4 or VP7 protein, is important for evaluating the circulation and pathogenesis of RV. Finally, the presence of one G2P[4]E1 strain reinforces the idea that new genotype combinations emerge through reassortment and independent segregation.
authors.affiliation: Departamento de Genética, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brasil.
authors.forename: Jéssica Wildgrube
authors.initials: JW
authors.lastname: Bertol
authors.affiliation: Departamento de Genética, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brasil.
authors.forename: Maria Clara Duarte
authors.initials: MC
authors.lastname: Fregolente
authors.affiliation: Departamento de Genética, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brasil.
authors.forename: Thabata Alessandra Ramos
authors.initials: TA
authors.lastname: Caruzo
authors.affiliation: Centro de Biologia Molecular e Engenharia Genética, Universidade Estadual de Campinas, Campinas, SP, Brasil.
authors.forename: Márcio José da
authors.initials: MJ
authors.lastname: Silva
authors.affiliation: Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil.
authors.forename: Veridiana
authors.initials: V
authors.lastname: Munford
authors.affiliation: Faculdade de Ciências Médicas, Santa Casa de São Paulo, São Paulo, SP, Brasil.
authors.forename: Marco Aurélio Palazzi
authors.initials: MA
authors.lastname: Sáfadi
authors.affiliation: Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil.
authors.forename: Maria Lucia
authors.initials: ML
authors.lastname: Rácz
authors.affiliation: Departamento de Genética, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brasil.
authors.forename: Maria Silvia Viccari
authors.initials: MS
authors.lastname: Gatti
mesh_terms: D000328:Adult; D000595:Amino Acid Sequence; D000956:Antigens, Viral / Q000302:isolation & purification*; D001483:Base Sequence; D001938:Brazil; D002648:Child; D005243:Feces / Q000821:virology; D008040:Genetic Linkage / Q000235:genetics; D014644:Genetic Variation; D005838:Genotype; D006023:Glycoproteins / Q000235:genetics*; D006801:Humans; D007124:Immunoenzyme Techniques; D008969:Molecular Sequence Data; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics* / Q000302:isolation & purification; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012401:Rotavirus / Q000145:classification / Q000235:genetics* / Q000276:immunology; D016415:Sequence Alignment; D014118:Toxins, Biological / Q000235:genetics*; D017361:Viral Nonstructural Proteins / Q000235:genetics*
chemical_list: D000956:Antigens, Viral; D006023:Glycoproteins; C081369:NS28 protein, rotavirus; D012367:RNA, Viral; D014118:Toxins, Biological; D017361:Viral Nonstructural Proteins