Keratin protein

Keratin proteins are a large family of structural fibrous proteins present mainly in epithelial cells, where they form intermediate filaments providing mechanical strength and resilience to tissues such as skin, hair, nails, and internal epithelial linings[4][7][8]. Over 50 functional keratin genes exist in humans, classified into two main types: Type I (acidic) and Type II (basic/neutral). Keratins form heterodimers and then higher-order filament structures with critical roles in protecting cells from mechanical and non-mechanical stress, anchoring desmosomes for strong cell-cell adhesion, regulating cell proliferation and differentiation, and participating in signaling pathways, wound repair, and tissue regeneration[3][6][10]. They have no known small-molecule drug interactions or classic pharmacological targeting, but specific keratin expression patterns serve as essential biomarkers for diagnosing epithelial tumors and defining stages of cell differentiation[3]. Mutations in keratin genes cause a spectrum of inherited diseases affecting skin fragility. “Keratin proteins” refers to a broad class, not a single molecular entity or canonical drug/therapeutic target, making the term imprecise for drug discovery or targeting[3][4][7][8].

Other names

Type I keratinType II keratinCytokeratinAlpha-keratinBeta-keratin