Figure 1.

Late phase of the HIV-1 replication cycle. Heterogeneous transcriptional start site usage affords 5′-capped transcripts beginning with a single guanosine that function as genomes (gRNA) and are packaged as dimers, as well as 5′-capped transcripts beginning with two (minor species, not shown) or three guanosines that function as mRNAs (5ʹ-leader, coding region, and Rev-binding sites of the viral RNA shown in black, red, and gray, respectively).