Sequence of the VP7 gene of chicken rotavirus Ch2 strain of serotype 7 rotavirus.

The gene that encodes the VP7 protein of the Ch2 strain of group A chicken rotavirus (serotype G7) was sequenced, and its deduced amino acid sequence analyzed. The gene is 1067 bp in length and contains a single long open reading frame of 987 nt, capable of encoding a protein of 329 amino acids. Amino acid homology of the chicken rotavirus VP7 to the corresponding protein of rotaviruses representing each of the other twelve G serotypes ranged from 58 to 63%. In addition, the VP7 protein of the Ch2 strain contains a unique amino acid sequence in variable regions VR5 (A), VR7 (B), or VR8 (C), which is consistent with previous studies indicating that these three regions are involved in G serotype specificity. The VP7 protein had amino acid homology of 19 or 33% with that of groups B (ADRV) or C (Cowden) rotavirus strains, respectively. Attempts to produce reassortants in vivo or in vitro between the Ch2 strain and strains belonging to group A or C rotavirus were unsuccessful. The low level of nucleotide identity in the 5' end noncoding region of the VP7 gene between the Ch2 and the group A or C rotaviruses may account for this failure.