Enables protein kinase activity. Involved in intracellular signal transduction and positive regulation of JUN kinase activity. Acts upstream of or within several processes, including chorionic trophoblast cell differentiation; male germ-line sex determination; and placenta development. Located in cytoplasm. Is expressed in several structures, including central nervous system; future brain; and genitourinary system. Orthologous to human MAP3K4 (mitogen-activated protein kinase kinase kinase 4). [provided by Alliance of Genome Resources, Apr 2022]