Enables protein serine/threonine kinase activity. Involved in several processes, including positive regulation of gluconeogenesis; response to glucagon; and response to thyroid hormone. Located in nucleus. Part of protein-containing complex. Colocalizes with Z disc. Biomarker of hyperthyroidism and obesity. Human ortholog(s) of this gene implicated in Peutz-Jeghers syndrome; familial melanoma; female reproductive organ cancer (multiple); and pancreatic cancer. Orthologous to human STK11 (serine/threonine kinase 11). [provided by Alliance of Genome Resources, Apr 2022]