Retina And Anterior Neural Fold Homeobox Protein (RAX)

RAX encodes a homeobox-containing transcription factor that functions in eye development. The gene is expressed early in the eye primordia, and is required for retinal cell fate determination and also regulates stem cell proliferation. Mutations in this gene have been reported in patients with defects in ocular development, including microphthalmia, anophthalmia, and coloboma.

The predicted amino acid sequence of the Xenopus Rx genes showed that each gene contained a highly conserved paired-like homeodomain, an octopeptide typical of this homeobox gene subfamily. They also isolated human, zebrafish, Drosophila, and murine Rx genes.