Fig 2.

Design of subgenomic reporter constructs. (A) The subgenomic reporter constructs. SIV sequences starting at SA5 or SA6 were placed directly downstream of the SV40 promoter in the pGL3-control plasmid (Promega), and the second codon of the Rev or Env ORF was fused to the luciferase gene in order to preserve the Kozak motif. The uAUGs are depicted by white circles and the regular start codons by black circles. (B) The inactivating mutations for each AUG. These mutations were chosen to be silent in the overlapping Tat ORF for future testing in the full-length SIV genome. The 4a mutation is a single nucleotide insertion (underlined) that fuses uAUG4 to the Rev ORF and simultaneously inactivates the Rev AUG.