SKI protein

The Ski protein is a nuclear protooncoprotein that is associated with tumors at high cellular concentrations. Ski has been shown to interfere with normal cellular functioning by both directly impeding expression of certain genes inside the nucleus of the cell as well as disrupting signaling proteins that activate genes.

Ski negatively regulates transforming growth factor-beta (TGF-beta) by directly interacting with Smads and repressing the transcription of TGF-beta responsive genes. This has been associated with cancer due to the large number of roles that peptide growth factors, of which TGF-beta are a subfamily, play in regulating cellular functions such as cell proliferation, apoptosis, specification, and developmental fate.

The name Ski comes from the Sloan-Kettering Institute where the protein was initially discovered.

Structure

Gene

The SKI proto-oncogene is located at a region close to the p73 tumor suppressor gene at the locus 1p36.3 locus of a gene, suggesting a similar function to the p73 gene.