THE ONLY DOMAIN WHICH DISTINGUISHES EPSTEIN-BARR-VIRUS LATENT MEMBRANE PROTEIN-2A (LMP2A) FROM LMP2B IS DISPENSABLE FOR LYMPHOCYTE INFECTION AND GROWTH TRANSFORMATION INVITRO - LMP2A IS THEREFORE NONESSENTIAL

Using second-site homologous recombination, Epstein-Barr virus (EBV) recombinants were constructed which carry an LMP2A mutation terminating translation at codon 19. Despite the absence of LMP2A or LMP2A cross-reactive protein, the recombinants were able to initiate and maintain primary B-lymphocyte growth transformation in vitro. EBNA1, EBNA2, and LMP1 expression was unaffected by the LMP2A mutation. The LMP2A mutant recombinant EBV-infected lymphoblastoid cell lines (LCLs) were identical to wild-type recombinant EBV-infected control LCLs with respect to initial outgrowth, subsequent growth, sensitivity to limiting cell dilution, sensitivity to low serum, and growth in soft agarose. The permissivity of LCLs for lytic EBV infection and virus replication was also unaffected by the LMP2A mutation.