Seems to act as a chloride ion channel (By similarity). Plays a role in retina development (PubMed:30157172). Within the endoplasmic reticulum (ER), localizes to the mitochondria-associated ER membrane, a zone of contact between the ER and mitochondrial membranes. Expressed in the hindbrain, swim bladder and the eye at 1 day post fertilization (dpf) with increased expression at 3 dpf (PubMed:30157172). At 3 dpf, most prominent expression in the retina, with strong exxpression in the ganglion cell layer, outer nuclear layer and the retinal pigmented epithelium (PubMed:30157172). Knockout leads to lethality at 11 dpf, with knockout larvae exhibiting abnormalities in various retinal layers including the inner plexiform layer, the outer nuclear layer and the rod photoreceptor layer and decreased function of the photoreceptor cone cells (PubMed:30157172). Morpholino knockdown results in reduced eye size with proportionately decreased lens size, thinner inner plexiform layer and outer nuclear layer after 36 hours post fertilization (hpf) (PubMed:30157172). No change in the inner nuclear layer, but increased apparent thickness of the ganglion cell layer (PubMed:30157172). Reduced number of rod cells, with existing rod cells exhibiting an abnormal morphology or pyknotic appearance, decreased opsin levels and disrupted photoreceptor cell bodies (PubMed:30157172). Belongs to the chloride channel MCLC family.