  Rotavirus (RV) is the major etiologic agent of severe infantile
gastroenteritis; its genome has 11 segments of double stranded RNA, encoding 12
proteins. The non-structural protein 4 (NSP4) encoded by segment 10 is
multifunctional. The aim of this study is to analyze the selective pressure
driving the NSP4 of RV, through the ratio of non-synonymous substitutions per
synonymous substitutions (dN/dS). Our results show that NSP4 is under negative
evolutionary pressure (84.57% of the amino acid sequence) and no site was found
under positive selection. This may support other evolutionary studies of
different RV proteins or viral agents.
