Neuropsin (Opn5): a novel opsin identified in mammalian neural tissue11Nucleotide sequence data reported are available in GenBank database under the accession numbers AY318865 and BK001605 (mouse) and AY377391 (human).

AbstractWe have cloned and characterised the expression of a new opsin gene, neuropsin (Opn5), in mice and humans. Neuropsin comprises seven exons on mouse chromosome 17. Its deduced protein sequence suggests a polypeptide of 377 amino acids in mice (354 in humans), with many structural features common to all opsins, including a lysine in the seventh transmembrane domain required to form a Schiff base link with retinaldehyde. Neuropsin shares 25–30% amino acid identity with all known opsins, making it the founding member of a new opsin family. It is expressed in the eye, brain, testis and spinal cord