Predicted to enable calcium ion binding activity. Involved in several processes, including liver development; positive regulation of phagocytosis; and response to lipopolysaccharide. Located in extracellular space. Part of protein-containing complex. Human ortholog(s) of this gene implicated in autosomal dominant thrombophilia due to protein S deficiency; autosomal recessive thrombophilia due to protein S deficiency; cerebral infarction; and protein S deficiency. Orthologous to human PROS1 (protein S). [provided by Alliance of Genome Resources, Apr 2022]