Enables insulin receptor binding activity. Involved in response to cAMP; response to cytokine; and response to peptide hormone. Located in extracellular space. Colocalizes with cytoplasm. Biomarker of Alzheimer's disease. Human ortholog(s) of this gene implicated in diabetic retinopathy; glucose metabolism disease (multiple); insulinoma; and pancreatic cancer. Orthologous to several human genes including INS (insulin). [provided by Alliance of Genome Resources, Apr 2022]