SKI plays a crucial role in cellular processes as a transcriptional regulator, particularly in the context of TGFβ signaling pathways. SKI protein is primarily located in the nucleus, where SKI protein interacts with Smad proteins to modulate gene expression. This nuclear localization is vital because SKI protein effectively represses Smad-mediated transcriptional activation, thereby inhibiting TGFβ-induced cell growth and extracellular matrix production. SKI protein contains five tandem repeats in its C-terminal domain and two leucine zipper motifs, which are essential for DNA binding capabilities and the formation of homodimers and heterodimers.