Signal transduction in keratinocytes.

Keratinocytes, a key cellular component both for homeostasis and pathophysiologic processes of the skin, secrete a number of cytokines and their proliferation and differentiation are stimulated by a variety of biological factors. The major mechanism by which cells (keratinocytes) respond to extracellular signals, is changing in protein phosphorylation. The protein phosphorylation is a consequence of the ligand/receptor binding which leads to activation of several transduction systems. In this review we emphasize on different signal transduction pathways in keratinocytes (tyrosine kinases, PKA, PKC, MAPK, casein kinase 2 etc.).