FIG. 3.

Evidence for transcription from a DNA molecule carrying an LTR-LTR junction. (a) Location of transcription start sites within tandem LTR repeats of a two-LTR circle and representation of the U5-U3 viral transcript expressed from the upstream promoter. The U3, R, and U5 sequences within the LTR are indicated. Arrowheads, transcription start sites. (b) Kinetic analysis of U5-U3 RNA synthesis in CEM cells infected by the VSV-G-pseudotyped HIV-1 R7 virus. Values are means ± standard errors of the means. Depicted results were obtained from a representative experiment.