Truncated forms of the polyomavirus middle T antigen can substitute for the small T antigen in lytic infection

Cloned polyomavirus genomes encoding the small T antigen or truncated forms of the middle T antigen facilitated the growth of genomes encoding only the large T antigen in mouse 3T6 cells. We conclude that an N-terminal domain of the middle T antigen, in the appropriate cellular location, can substitute for the small T antigen during lytic infection.