KLF4 is a member of the erythroid Kruppel-like factor (EKLF) multigene family that is highly expressed in the differentiating layers of the epidermis. KLF4 plays a critical role in the differentiation of epithelial cells and is essential for normal gastric homeostasis. It regulates the expression of key transcription factors during embryonic development. KLF4 plays an important role in maintaining embryonic stem cells, and in preventing their differentiation. It is required for establishing the barrier function of the skin and for postnatal maturation and maintenance of the ocular surface.