FIG. 2.

IM1 cells support WT levels of MLV reverse transcription and integration. (A) CHO-K1, IM1, and MCL7 cell lines were challenged with the VSV-G-pseudotyped MLV vector LEGFP, and total DNA was isolated at 0 or 24 hpi, DNA concentration was quantitated by A₂₆₀, and a real-time PCR amplification analysis was performed to measure the levels of viral DNA. (B) CHO-K1, IM1, and MCL7 cells were challenged with the same VSV-G-pseudotyped MLV vector as that used in panel A, and total DNA was harvested at 1 or 18 days postinfection for real-time PCR quantitation of viral DNA products. The chemically mutagenized cell line MCL1 displays a strong block to MLV reverse transcription, while the MCL7 cell line displays a strong block to MLV DNA integration (6). The data shown are the average mean values obtained in independent experiments performed with triplicate samples, and each is representative of three independent experiments. Error bars indicate the standard deviations of the data. P values were calculated using a standard Student's t test.