Cloning and Bioinformatics Analysis of the E1 Gene of Bovine Viral Diarrhea Virus Strain Yak

According to the sequence data of BVDV strain published by GenBank,two set of primers were designed and used to amplify E1 gene of BVDV strain yak by the method of nested reverse transcription polymerase chain reaction(RT-PCR).A specific 585 bp DNA segment was amplified,which was cloned into pMD18-T vector.The positive recombinant clone was identified by plasmid PCR and restriction enzyme digestion.The recombinant plasmid was sequenced and compared with BLAST on line.The E1 gene of BVDV strain yak exhibits the highest homology with strain Osloss,but they only shares 73.3% nucleotide sequence identity and 82.6% amino acid identity,showing that the E1 gene of BVDV strain yak have great variation.This may be the virus to adapt to yak and the ecological environment of the plateau,or the virus may also have an independent source of genetic.