Forms nonselective divalent cation-conducting channels which mediate the influx of Na(+), Ca(2+), Mg(2+), Mn(2+), Ba(2+), and Ni(2+) into the cytoplasm, leading to membrane depolarization (, ). Impermeable to zinc ions . In addition, forms heteromultimeric ion channels with TRPM3 which are permeable for calcium and zinc ions . Essential for the depolarizing photoresponse of retinal ON bipolar cells. It is part of the GRM6 signaling cascade. May play a role in metastasis suppression (By similarity). May act as a spontaneously active, calcium-permeable plasma membrane channel.
Subcellular locations: Cell membrane, Endoplasmic reticulum membrane, Cell projection, Axon
Expressed in the retina where it localizes to the outer plexiform layer. Specifically, it is expressed in retinal bipolar cells (BPCs) of the ON subtype . Highly expressed in benign melanocytic nevi and diffusely expressed in various in situ melanomas, but not detected in melanoma metastases. Also expressed in melanocytes and pigmented metastatic melanoma cell lines. In melanocytes expression appears to be regulated at the level of transcription and mRNA processing.