The protein encoded by this gene forms a tetrameric cation channel that is permeable to calcium, sodium, and potassium and is regulated by free intracellular ADP-ribose. The encoded protein is activated by oxidative stress and confers susceptibility to cell death. Alternative splicing results in multiple transcript variants encoding distinct protein isoforms. Additional transcript variants of this gene have been described, but their full-length nature is not known. [provided by RefSeq, Feb 2016].