Cone Rod Homeobox Protein (CRX)

CRX is a photoreceptor-specific transcription factor which plays a role in the differentiation of photoreceptor cells. This homeodomain protein is necessary for the maintenance of normal cone and rod function. Mutations in this gene are associated with photoreceptor degeneration, Leber congenital amaurosis type III and the autosomal dominant cone-rod dystrophy 2. Several alternatively spliced transcript variants of this gene have been described, but the full-length nature of some variants has not been determined.The CRX homeodomain is located near the amino terminus at residues 39 to 99 and belongs to the prd class. Additional domains of the CRX protein include the WSP motif and the OTX tail. The CRX gene was expressed as an abundant 4.5-kb transcript in retina but not in any other of 10 tissues or cells examined.