Structural component of the gap junctions and the hemichannels involved in the ATP release and nucleotide permeation ( ). May play a role as a Ca(2+)-leak channel to regulate ER Ca(2+) homeostasis . Plays a critical role in oogenesis .
Subcellular locations: Cell membrane, Cell junction, Gap junction, Endoplasmic reticulum membrane
Widely expressed . Highest expression is observed in oocytes and brain . Detected at very low levels in sperm cells .