Figure 3

Lizard and human A1 proteins inhibit ORF1p encoding hL1 and ZfL2-1, but not ZfL2-2 retrotransposition. (A) HeLa cells were co-transfected with ZfL2-1, ZfL2-2 or hL1 retrotransposon plasmids and effector plasmids encoding human A3A, human A1 (hA1), or lizard A1a protein variants F3 and F8 (lizA1F3 and lizA1F8). Relative retrotransposition efficiency was determined by counting the fixed and stained neomycin resistant colonies, formed after 12 days of G418 selection, and calculated by setting the value obtained for control cells co-transfected with retrotransposon plasmid and an empty vector at 100%. Data are the means ± SD of three independent experiments. ***P < 0.001, **P < 0.01, *P < 0.05, t-test. (B) The expression of Myc epitope-tagged lizard proteins in mammalian cells was confirmed in the HEK293T cell model by immunoblotting. GAPDH expression levels were used as a loading control.