The TGFβ/SMAD GFP reporter lentivirus is designed for monitoring the activity of the TGFβ/SMAD signaling pathway. The transforming growth factor beta (TGFβ) signaling pathway is involved in many cellular processes in both the adult organism and the developing embryo including cell growth, cell differentiation, apoptosis, cellular homeostasis and other cellular functions. TGFβ signaling induces phosphorylation and activation of the SMAD2 and SMAD3 proteins, which then form complexes with the mediator SMAD4. These SMAD complexes then translocate to the nucleus, where they activate the expression of TGFβ-responsive genes. This TGFβ/SMAD reporter lentivirus expresses GFP under the control of a minimal (m)CMV promoter and tandem repeats of the SMAD transcriptional response element (TRE). It can be used to monitor the transcriptional activity of the TGFβ/SMAD signaling pathway. Transduced cells can be selected by puromycin.