Analysis of NSP4 Gene and Its Association with Genotyping of Rotavirus Group A in Stool Samples

Non-structural protein 4 (NSP4) is a critical protein for rotavirus (RV) replication and assembly. This protein has multiple domains and motifs that predispose its function and activity. NSP4 has a sequence divergence in human and animal RVs. Recently, 14 genotypes (E1-E14) of NSP4 have been identified, and E1 and E2 have been shown to be the most common genotypes in human.
The gene and protein sequence of NSP4 in RV-positive samples were inspected with the aim of NSP4 genotyping and variation analysis in viroporin and other domains. P and G typing of RV samples have been carried out by WHO primers using a semi-multiplex PCR method. Non-typeable RV samples were amplified by conserved primers and sequenced.
In viroporin and enterotoxin, conserved sequence was detected, and amino acids substitution with the same biochemical properties was found.
Moreover, association of NSP4 genotype with P or G genotyping G1/G9 correlates with E1 genogroups. In electrophoretyping of RV, E2 genotype had short pattern when compared to E1.