FIG. 6.

LINE-1 elements expressed in pluripotent cells are produced from a range of L1s. (a) Pie charts showing the representations and percentages of L1 subfamilies expressing AS-L1 transcripts in hESCs and hEC cells (the cell line name is indicated above each pie chart). (b) Both sense and antisense promoters from the 5′ UTR of older LINE-1 elements are active in hEC cells. Each graph shows the quantification of the activity of the sense and antisense L1 promoters from L1PA1, L1PA2, L1PA3, L1PA4, L1PA6, L1PA7, L1PA8, and L1PA10 elements in PA-1 hEC cells. The graphs show the firefly activities (normalized to Renilla luciferase activity; see Materials and Methods) of the sense (S) and antisense (AS) promoters measured in triplicate (the standard deviation of the assay is indicated in each graph). As a control, PA-1 cells were transfected with a promoterless construct (pgl3basic). Similar data were obtained with 2102Ep and N-Tera2D1 cells (see Fig. 5 posted at http://www.juntadeandalucia.es/fundacionprogresoysalud/repositorio/files/0000/0080/16._MCB00561_SupInfo_final.pdf).