May be involved in the maintenance of both the function and the viability of sensory neurons, including photoreceptors and olfactory neurons. In the retina, isoform 1 may be required for rod function and isoform 2 for cone viability and function. Both isoforms are expressed in retina, in the photoreceptor layer, and throughout the olfactory sensory neuron layer of the nasal epithelium, in neurons. Also expressed at low levels in brain and testis. At 10 months of age, mutant animals show signs of photoreceptor dysfunction. The progressive loss of cone function is followed by cone cell death, while in rods, the outer segment length id reduced, but not rod cell death is not observed. At 12 months, mice present a stronger age-dependent impairment of fine odor discrimination than their wild-type counterparts. Belongs to the nucleoredoxin family.