The values represent relative promoter activities as ratios of the luciferase activity expressed by plasmids containing promoters under study to the luciferase activity expressed by a pGL3-PV plasmid
HEK293T ishXrn1 cells were treated with doxycycline for 3-4 days to induce knock down of Xrn1, then transfected with the luciferase reporters containing 99 bp, 51 bp, 27 bp or 15 bp insertions from th