Keratinocyte Differentiation Pathways

Keratinocyte differentiation pathways refer to the complex, multi-step biological processes by which basal keratinocytes in the epidermis mature into specialized, terminally differentiated cells that form the skin barrier. This process is essential for maintaining skin integrity and function, as it leads to the formation of the stratum corneum—the outermost protective layer of the skin. Key pathways involved include Calcium signaling, MAP Kinase Pathways, IKKα/NF-kB Pathway, and Retinoic Acid Signaling. Abnormalities in these pathways contribute to several skin diseases such as Netherton syndrome and Psoriasis.

Retinoids inhibit keratinocyte differentiation through nuclear hormone receptors RARs/RXRs that modulate transcriptional programs relevant to epidermal development.