Pro-islet amyloid polypeptide (IPR000443)

Short name: Pro-islet_amyloid_polypep

Overlapping homologous superfamilies


Family relationships


Islet amyloid polypeptide (IAPP) (also known as diabetes-associated peptide or amylin) is a pancreatic islet hormone that is stored with insulin in beta cell granules [PMID: 2192709]. IAPP has a propensity to form islet cell-disrupting amyloid deposits, and opposes the action of insulin in peripheral tissues; the peptide may therefore have a significant role in the development of Type 2 diabetes mellitus [PMID: 2192709]. It is thought that an intrinsic structural motif of IAPP, which only occurs in species that develop age-associated or Type 2 diabetes (e.g., Homo sapiens (Human) and Felis silvestris catus (Cat)), is linked to its amyloidogenicity [PMID: 2192709]. IAPP is a short, 37-residue peptide. The hormone selectively inhibits insulin-stimulated glucose utilisation and glycogen deposition in muscle, but does not affect adipocyte glucose metabolism. The sequences of amylin and the calcitonin gene-related peptides (CGRPs) show strong similarity: both peptides have a conserved N-terminal intramolecular disulphide bridge, and both have a C-terminal glycine, which suggests that the C-terminal residue of amylin, like that of CGRP, is amidated [PMID: 2690069]. Near- and far-UV CD spectra of human alpha CGRP, analogues and fragments of CGRP, and amylin have been recorded in aqueous solution and in trifluoro- ethanol/water mixtures [PMID: 2039456]. The peptides were shown to contain significant amounts of alpha-helix in aqueous solution, this amount increasing upon addition of TFE. Amylin appears to contain less helix than CGRP [PMID: 2039456].

This entry represents the propeptide (Pro-islet amyloid polypeptide) prior to cleavage into islet amyloid polypeptide.

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0005179 hormone activity

Cellular Component

GO:0005576 extracellular region

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.