This gene encodes an integral membrane protein, which is localized to the endoplasmic reticulum, and functions as a phosphoinositide phosphatase that hydrolyzes phosphatidylinositol 3-phosphate, phosphatidylinositol 4-phosphate, and phosphatidylinositol 3,5-bisphosphate. Deletion of this gene in mouse results in preimplantation lethality. Other studies suggest that this gene is also involved in the organization of golgi membranes and mitotic spindles. Alternatively spliced transcript variants have been found for this gene. A C-terminally extended isoform is also predicted to be produced by the use of an alternative in-frame, downstream translation termination codon via a stop codon readthrough mechanism.[provided by RefSeq, Dec 2017] see less This gene encodes an integral membrane protein, which is localized to the endoplasmic reticulum, and functions as a phosphoinositide phosphatase that hydrolyzes phosphatidylinositol 3-phosphate, phosphatidylinositol 4-phosphate, and phosphatidylinositol 3,5-bisphosphate. Deletion of this gene in mouse results in preimplantation lethality. Other studies suggest that this gene is also involved in... see more