Deletion of the M2-2 gene from avian metapneumovirus subgroup C impairs virus replication and immunogenicity in Turkeys

The second matrix (M2) gene of avian metapneumovirus subgroup C (aMPV-C) contains two overlapping open reading frames (ORFs), encoding two putative proteins, M2-1 and M2-2. Both proteins are believed to be involved in viral RNA transcription or replication. To further characterize the function of the M2-2 protein in virus replication, the non-overlapping region of the M2-2 ORF was deleted from an infectious cDNA clone of the aMPV-C strain, and a...