Enables receptor signaling protein tyrosine kinase inhibitor activity. Involved in several processes, including animal organ development; negative regulation of bone mineralization; and positive regulation of bone resorption. Located in collagen-containing extracellular matrix and extracellular space. Part of protein-containing complex. Human ortholog(s) of this gene implicated in alopecia-mental retardation syndrome 1; coronary artery disease; and type 2 diabetes mellitus. Orthologous to human AHSG (alpha 2-HS glycoprotein). [provided by Alliance of Genome Resources, Apr 2022]