A second post-transcriptional trans-activator gene required for HTLV-III replication.

Evidence is provided for the existence of a seventh gene in the genome of human T-lymphotropic virus type III/lymphadenopathy-associated virus. The gene is necessary for replication and acts post-transcriptionally to relieve negative regulation of the messenger RNA for the virion capsid and envelope proteins. These observations suggest mechanisms for regulating both the latent and lytic phases of the virus life cycle.