Enables magnesium ion binding activity and protein serine/threonine kinase activity. Involved in several processes, including peptidyl-serine phosphorylation; skin development; and spermatid development. Located in motile cilium. Is expressed in embryo; seminiferous tubule; spermatid; and testis. Orthologous to several human genes including TSSK1B (testis specific serine kinase 1B). [provided by Alliance of Genome Resources, Apr 2022]