Fig. 5.

Sense and antisense promoter activities of pig L1 5′UTRs and ERV6 LTRs. a Schematics of vectors used for promoter activity detection by luciferase assay. The sense and antisense 5′UTR/L1 and LTRs of ERVs from young and putatively active subfamilies of L1 were cloned into the pGL3-enhancer luciferase reporter vector to investigate the promoter activity. b Sense and antisense promoter activities of ERV6A and ERV6B LTRs measured by luciferase assay. c Sense and antisense promoter activities of young L1 5′UTRs (L1D) measured by luciferase assay. Eight sense and four antisense L1 5′UTRs from different subfamilies of L1D family were cloned as described in the methods, and two 5′UTRs (hL1–3 and hL1-M) of active L1 s from human and one 5′UTR (mL1) of active L1 from mouse were used as positive controls