Rotavirus Department, National Institute of Virology, 20-A, Dr. Ambedkar road, Pune-411 001, India.
Abstracts of the papers presented at the XVIII National Conference of Indian Virological Society at Post Graduate Institute of Medical Education and Research, Chandigarh, India, December 11–13, 2008.
Group A rotaviruses of family Reoviridae are the most important etiological agents of severe gastroenteritis in children. Rotavirus G1P[8], G2P[4], G3P[8] and G4P[8] are commonly detected genotypes in human infections with predominance of G1P[8]. Although cultivation of rotaviruses is known since 1980, molecular changes in rotavirus genes during culture adaptation have not been reported. The present study was conducted to determine the variations in the structural genes of rotavirus strain G1P[8]. Rotavirus strainG1P[8] was isolated from the fecal specimen of a 2 year-old child with acute diarrhea and adapted to MA104 cell line. RT-PCR and nucleotide sequencing were carried out to obtain complete deduced amino acid sequences of all the structural proteins (VP1-VP4, VP6 and VP7) of wild type and culture adapted strains. Comparison of 4314 amino acid sequence of the structural genes of wild type with that of culture adapted strain revealed identical sequence in all proteins except VP4. One nucleotide substitution (C-T) at position 146 observed passage 2 onwards resulted in the change of amino acid from alanine to valine (A-V) at position 46 in VP4. Comparative analysis of all available wild type VP4 proteins showed uniqueness of the substitution (A-V) in the culture adapted strain and suggested involvement of VP4 gene during adaptation of G1P[8] strain to MA104 cells.
