title: Mutation distribution in the NSP4 protein in rotaviruses isolated from Mexican children with moderate to severe gastroenteritis.
abstract: The NSP4 protein is a multifunctional protein that plays a role in the morphogenesis and pathogenesis of the rotavirus. Although NSP4 is considered an enterotoxin, the relationship between gastroenteritis severity and amino acid variations in NSP4 of the human rotavirus remains unclear. In this study, we analyzed the sequence diversity of NSP4 and the severity of gastroenteritis of children with moderate to severe gastroenteritis. The rotavirus-infected children were hospitalized before the rotavirus vaccine program in Mexico. All children had diarrhea within 1-4 days, 44 (88%) were vomiting and 35 (70%) had fevers. The severity analysis showed that 13 (26%) cases had mild gastroenteritis, 23 (46%) moderate gastroenteritis and 14 (28%) severe. NSP4 phylogenetic analysis showed three clusters within the genotype E1. Sequence analysis revealed similar mutations inside each cluster, and an uncommon variation in residue 144 was found in five of the Mexican NSP4 sequences. Most of the amino acid variations were located in the VP4 and VP6 binding site domains, with no relationship to different grades of gastroenteritis. This finding indicates that severe gastroenteritis caused by the rotavirus appears to be related to diverse viral or cellular factors instead of NSP4 activity as a unique pathogenic factor.
authors.affiliation: Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, Av. Universidad S/N Ciudad Universitaria, San Nicolás de los Garza, Nuevo León, CP. 66451, Mexico. lupitaglezo@hotmail.com
authors.forename: Guadalupe
authors.initials: G
authors.lastname: González-Ochoa
authors.forename: Griselda E
authors.initials: GE
authors.lastname: Menchaca
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Hernández
authors.forename: Cristina
authors.initials: C
authors.lastname: Rodríguez
authors.forename: Reyes S
authors.initials: RS
authors.lastname: Tamez
authors.forename: Juan F
authors.initials: JF
authors.lastname: Contreras
mesh_terms: D000595:Amino Acid Sequence; D005759:Gastroenteritis / Q000473:pathology / Q000821:virology*; D005838:Genotype; D006023:Glycoproteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D007223:Infant; D008297:Male; D008800:Mexico; D008969:Molecular Sequence Data; D009154:Mutation; D010802:Phylogeny; D017434:Protein Structure, Tertiary; D012401:Rotavirus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification* / Q000378:metabolism; D012400:Rotavirus Infections / Q000473:pathology / Q000821:virology*; D014118:Toxins, Biological / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D017361:Viral Nonstructural Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
chemical_list: D006023:Glycoproteins; C081369:NS28 protein, rotavirus; D014118:Toxins, Biological; D017361:Viral Nonstructural Proteins