FIGURE 3.

Dose dependency and specificity of Ct-mediated IRES stimulation. (A) Ct cells were tet-induced from 30 min up to 16 h. At given intervals, uncapped c-myc 5′ UTR (black bars) or m⁷GTP-capped β-globin leader (gray bars) reporter RNAs were transfected and cells were lysed 6 h thereafter. The lysates were tested by immunoblot with myc-tag or tubulin antibodies (top panel). (B) Ct cells were tet-induced for 16 h and transfected with uncapped reporter RNAs under the control of the indicated sequences: the c-myc- or VEGF- 5′ UTRs; the EMCV-, HCV-, or CBV3 IRESs; the inverted c-myc 5′ UTR. RLuc activity was measured 6 h after transfection and lysates were tested by immunoblot with myc-tag and tubulin antibodies (top panel).