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- *********************************************
- * Calcitonin / CGRP / IAPP family signature *
- *********************************************
-
- Calcitonin [1] is a 32 amino acid polypeptide hormone that causes a rapid but
- short-lived drop in the level of calcium and phosphate in the blood, by
- promoting the incorporation of these ions in the bones. Alternative splicing
- of the gene coding for calcitonin produces a distantly related peptide of 37
- amino acids, called calcitonin gene-related peptide (CGRP). CGRP induces
- vasodilatation in a variety of vessels, including the coronary, cerebral
- and systemic vasculature. Its abundance in the CNS also points toward a
- neurotransmitter or neuromodulator role.
-
- Islet amyloid polypeptide (IAPP) [2] (also known as diabete-associated peptide
- (DAP), or amylin) is a peptide of 37 amino acids that selectively inhibits
- insulin-stimulated glucose utilization and glycogen deposition in muscle,
- while not affecting adipocyte glucose metabolism. Structurally, IAPP is
- closely related to CGRP.
-
- Two conserved cysteines in the N-terminal of these peptides are known to be
- involved in a disulfide bond. The C-terminal residue of all three peptides is
- amidated.
-
- ****************
- xCxxxxxCxxxxxxxxxxxxxxxxxxxxxxxxxxxx-NH(2)
- | | Amide group
- +-----+
-
- 'C': conserved cysteine involved in a disulfide bond.
- '*': position of the pattern.
-
- The pattern we developed for this family of peptides includes the region of
- the disulfide bond.
-
- -Consensus pattern: C-[SAGDN]-[STN]-x(0,1)-[SA]-T-C-[VMA]-x(3)-[LYF]-x(3)-
- [LYF]
- [The two C's are linked by a disulfide bond]
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
- -Last update: June 1992 / Pattern and text revised.
-
- [ 1] Breimer L.H., McIntyre I., Zaidi M.
- Biochem. J. 255:377-390(1988).
- [ 2] Nishi M., Sanke T., Nagamatsu S., Bell G.I., Steiner D.F.
- J. Biol. Chem. 265:4173-4176(1990).
-