Requirement for the c-Maf transcription factor in crystallin gene regulation and lens development

The vertebrate lens is a tissue composed of terminally differentiated fiber cells and anterior lens epithelial tells. The abundant, preferential expre ssion of the soluble proteins called crystallins creates a transparent, ref ractive index gradient in the lens. Several transcription factors such as P ax6, Sox1, and L-Maf have been shown to regulate lens development Here we s how that mice lacking the transcription factor c-Maf are microphthalmic sec ondary to defective lens formation, specifically from the failure of poster ior lens fiber elongation. The marked impairment of crystallin gene express ion observed is likely explained by the ability of c-Maf to transactivate t he crystallin gene promoter, Thus, c-Maf is required for the differentiatio n of the vertebrate lens.