FIGURE 8.

SnoN and ING2 collaborate to enhance TGF-β-dependent transcription. A, SnoN knockdown reduces ING2-dependent up-regulation of TGF-β-mediated transcription. Lysates of Mv1Lu cells transfected with the 3TP-luciferase and β-galactosidase reporter constructs together with the control or the SnoN RNAi plasmid and an empty mammalian expression vector or one encoding the ING2 protein and incubated in the absence or presence of TGF-β were subjected to luciferase and β-galactosidase assays as described for Fig. 1D. B, SnoN induces the ability of ING2 to promote TGF-β-dependent transcription. Mv1Lu cells were transfected with the reporter constructs as in Fig. 8A and with an ING2 expressing vector alone or together with a SnoN expressing plasmid. The cells were incubated with or without TGF-β, and the lysates were subjected to luciferase and β-galactosidase assays as described for Fig. 1D. C, ING2 knockdown inhibits SnoN enhancement of TGF-β-induced transcription. Lysates of Mv1Lu cells transfected with the reporter constructs as described for A together with a control or ING2 RNAi vector and an empty expression vector or one encoding SnoN and incubated in the absence or presence of TGF-β were subjected to luciferase and β-galactosidase assays as described for Fig. 1D. In the transfections described in each of B or C, a low amount (1-5 ng/well) of SnoN expressing vector was used (34). The data shown in each of A-C represent the means (±S.D.) of triplicate measurements from a representative experiment that was repeated three times.