Selectively inhibits insulin-stimulated glucose utilization and glycogen deposition in muscle, while not affecting adipocyte glucose metabolism. Interacts with IDE and INS. Can form homodimers. Interaction with INS inhibits homodimerization and fibril formation. The mature protein is largely unstructured in the absence of a cognate ligand, and has a strong tendency to form fibrillar aggregates. Homodimerization may be the first step of amyloid formation. Amyloid fibrils are degraded by IDE. IAPP is the peptide subunit of amyloid found in pancreatic islets of type 2 diabetic patients and in insulinomas. Belongs to the calcitonin family. Amylin entry