FIG. 1.

Incorporation of GaLV and MuLV Env proteins into retrovirus and lentivirus vectors. 293T cells were transiently transfected with either retrovirus (R) or lentivirus (L) vector components and the Env proteins indicated. Vector particles were partially purified from the supernatant by centrifugation through 20% sucrose, and both vector particles and cell lysates were subjected to Western analysis using antibodies raised against the MuLV TM protein that also recognize the GaLV TM. TM-R is the form of TM with the R peptide cleaved. The CA proteins from the vectors were used as loading controls and were detected using anti-p30 (MuLV) or anti-p24 (HIV-1) antibodies, respectively.