Indian Journal of Virology

Potato virus A (PVA) is an important member of the family Potyviridae. The virus alone or in combination with other potato viruses is responsible for tuber yield loss leading to degeneration of potato seed stock. The Indian isolate of PVA was immunocapture on 0.2 ml PCR tubes (Acygen) by using 100 ?l of virus specific IgG (2 ?g/ml). Viral cDNA was synthesized in the same tubes with the help of virus CP gene specific downstream primer. The viral sequence encoding the coat protein was specifically amplified by polymerase chain reaction using specific primer bordering the CP gene. The unique amplified product thus obtained was A-T cloned into pDrive (Qiagen) vector and cloning was confirmed by digestion with BamHI and NotI restriction enzymes and PCR of the transformed vector. Authenticity of the cloned gene was verified by sequence analysis. The nucleotide sequence and deduced amino acid sequence were compared with other PVA isolates and found to be 9099% identical at both the nucleotide and amino acid sequence level. Multiple sequence alignment of deduced amino acid sequence revealed considerable homology to other potyviruses. This is the first report of PVA coat protein gene sequence from India.