Enables protein serine/threonine kinase activity and transmembrane transporter binding activity. Involved in regulation of relaxation of cardiac muscle. Acts upstream of or within several processes, including G1/S transition of mitotic cell cycle; cardiac muscle contraction; and protein phosphorylation. Located in several cellular components, including T-tubule; axon initial segment; and intercalated disc. Is expressed in several structures, including central nervous system; heart ventricle; olfactory epithelium; renal vasculature; and retina. Orthologous to human CAMK2D (calcium/calmodulin dependent protein kinase II delta). [provided by Alliance of Genome Resources, Apr 2022]