title: [Genetic characterization of the non-structural protein NSP4 from epidemic strains of human rotavirus in China].
abstract: BACKGROUND
  To clarify the features of gene variation among epidemic strains of human rotavirus NSP4 in China.
  
  
  METHODS
  SP4 genes from 27 epidemic strains of human rotavirus isolated in different area of China in recent years were amplified with RT-PCR, the resulted cDNAs were cloned and sequenced. The sequences of full length cDNAs were compared with 10 rotavirus NSP4 sequences available in the GenBank using the Clustal x 1.8 TreeView32 and DNA Star softwares. The G serotype of VP7 was analysed by PCR.
  
  
  RESULTS
  The homology of the amino acid among the 27 rotavirus strains isolated in China was 81.7%-99.4%. Based on the variation of amino acid sequence, the virus strains can be divided into two groups, represented by Wa and KUN with the homology of 92.0%-99.4% and 92.0%-98.9% within each group, respectively. The diversity between the two groups were 16.6%-21.0%. The Wa group could further be separated into three subgroups, according to the diversity between those strains and the characterization in the highly variable domain. The association between VP7 serotype and NSP4 genotype was not strong.
  
  
  CONCLUSIONS
  The NSP4 gene of human rotavirus epidemic strains in China can be divided into Wa and KUN two groups, Wa group is the main group and contains three subgroups possessing characteristic amino acid sites. Samples isolated in the same year but not in the same area shared higher homology.
authors.affiliation: Medical School of Shandong University, Jinan 250012, China.
authors.forename: Da-yan
authors.initials: DY
authors.lastname: Wang
authors.forename: Jian-wei
authors.initials: JW
authors.lastname: Wang
authors.forename: Shu-shen
authors.initials: SS
authors.lastname: Xu
authors.forename: Le-ying
authors.initials: LY
authors.lastname: Wen
authors.forename: Yu-rong
authors.initials: YR
authors.lastname: Mao
authors.forename: Xiu-ping
authors.initials: XP
authors.lastname: Yu
authors.forename: Tao
authors.initials: T
authors.lastname: Hung
mesh_terms: D000956:Antigens, Viral; D036022:Capsid Proteins / Q000235:genetics*; D018076:DNA, Complementary / Q000032:analysis; D004279:DNA, Viral / Q000032:analysis; D003967:Diarrhea / Q000821:virology; D014644:Genetic Variation; D005838:Genotype; D006023:Glycoproteins / Q000235:genetics*; D006801:Humans; D010802:Phylogeny; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012401:Rotavirus / Q000235:genetics* / Q000302:isolation & purification; D017422:Sequence Analysis, DNA; D014118:Toxins, Biological; D017361:Viral Nonstructural Proteins / Q000235:genetics*
chemical_list: D000956:Antigens, Viral; D036022:Capsid Proteins; D018076:DNA, Complementary; D004279:DNA, Viral; D006023:Glycoproteins; C081369:NS28 protein, rotavirus; D014118:Toxins, Biological; C050779:VP7 protein, Rotavirus; D017361:Viral Nonstructural Proteins