Fig. 4.

Conservation of the HERV-FRD env locus and ORF on primate evolution. (A) Slot-blot of genomic DNA from simian, prosimian, cat, and mouse species, probed with a full-length HERV-FRD env fragment. The inferred date of insertion of HERV-FRD is indicated with an arrow on the primate phylogenetic tree on the left. NWM, New World monkey. (B) In vitro transcription/ translation assay of the human HERV-FRD env gene and of the orthologous genes from the indicated simian species. Env genes were PCR-amplified as schematized, submitted to in vitro transcription/translation (“control” is without DNA template), run on a polyacrylamide gel, and autoradiographed. The arrow points to the bands of the expected size.