Supplementary site interactions are critical for the binding of miR-30c to the 3΄-untranslated region of MTTP mRNA. (A) Interactions between wildtype (MTTP) and miR-30c are shown in the top. Next two structures show mutations introduced in the MTTP 3΄-UTR as green letters and predicted consequences of these mutations on the base pairing with miR-30c. (B) Cos-7 cells were first transfected with 50 nM of Scr or miR-30c. Next day cells were transferred to 6-well plates and transfected with 1 μg f wildtype (WT) or different indicated mutants. After 24 h, cells were used to measure luciferase activity. Values in one WT sample was normalized to one and other values were normalized to this value. There were no significant differences amongst different Scr groups. Significant differences between Scr and miR-30c are shown as *. Significant differences between WT and mutant MTTP constructs are shown as #. Mean ± SD, n = 3. **,## p < 0.01.