Recombinant pseudorabies virus as well as construction method and application thereof

The invention relates to the technical field of gene engineering, and particularly discloses a recombinant pseudorabies virus as well as a construction method and application thereof. The technical problem to be solved by the invention is how to reduce immunosuppression caused by pseudorabies virus. The recombinant pseudorabies virus provided by the invention does not contain a coding gene of UL48 protein. According to the invention, a pseudorabies virus gene-deleted attenuated strain is constructed by using a CRISPR/Cas9 gene editing technology, and the pseudorabies virus gene-deleted attenuated strain constructed by the method is subjected to specific deletion mutation at a UL48 gene part. The expression quantity of the I-type IFN gene induced by the pseudorabies virus gene deletion attenuated strain is obviously improved, stronger natural immune response can be generated, and the replication of the virus has no obvious difference. Therefore, the UL48 gene deletion mutation can significantly reduce immunosu