Is an ortholog of human PIK3C3 (phosphatidylinositol 3-kinase catalytic subunit type 3). Exhibits 1-phosphatidylinositol-3-kinase activity. Is involved in several processes, including determination of adult lifespan\; ecdysis, collagen and cuticulin-based cuticle\; and nematode larval development. Localizes to the cytoplasm\; nuclear outer membrane\; and nucleolus.