N protein mutants of porcine reproductive and respiratory syndrome virus

摘要

Disclosed is a pharmaceutical composition comprising a porcine reproductive and respiratory syndrome (PRRS) infectious agent selected from the group consisting of: a) a genetically modified PRRS virus comprising an N protein which has been modified in the NLS-2 region, such that the pat4, pat7 or pat8 motif has been interrupted by a deletion of one or more amino acids or by introduction of a nonconservative amino acid substitution, and wherein the genetically modified PRRS virus is attenuated; b) an infectious RNA molecule encoding the genetically modified PRRS virus of a); and c) an isolated polynucleotide molecule comprising a DNA sequence encoding the infectious RNA molecule of b). Also disclosed is a vaccine comprising of said composition, a method employing said composition, a transfected host cell containing said composition.