Enables diacylglycerol kinase activity. Involved in diacylglycerol metabolic process; lipid phosphorylation; and phosphatidic acid biosynthetic process. Located in several cellular components, including excitatory synapse; neuronal cell body; and postsynaptic density. Is active in glutamatergic synapse and synaptic vesicle. Is extrinsic component of postsynaptic density membrane and extrinsic component of presynaptic active zone membrane. Orthologous to human DGKI (diacylglycerol kinase iota). [provided by Alliance of Genome Resources, Apr 2022]