Enables protein kinase activity. Involved in cellular response to glucose starvation and macroautophagy. Acts upstream of or within several processes, including cellular response to starvation; phosphatidylinositol-3-phosphate biosynthetic process; and protein localization to phagophore assembly site. Located in phagocytic vesicle. Part of phosphatidylinositol 3-kinase complex, class III. Is expressed in Meckel's cartilage; cardiovascular system; limb; and skeleton. Orthologous to human PIK3C3 (phosphatidylinositol 3-kinase catalytic subunit type 3). [provided by Alliance of Genome Resources, Apr 2022]