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- ****************************************************
- * Glucagon / GIP / secretin / VIP family signature *
- ****************************************************
-
- A number of polypeptidic hormones, mainly expressed in the intestine or the
- pancreas, belong to a group of structurally related peptides [1,2]. Members of
- this family are:
-
- - Glucagon, which promotes hydrolysis of glycogen and lipids, and raises the
- blood sugar level.
- - Glucagon-like peptide 1 (GLP-1), a peptide of unknown function processed
- from the same precursor protein as that of glucagon.
- - Glucagon-like peptide 2 (GLP-2), a peptide of unknown function also
- processed from the glucagon precursor protein but which, in contrast to
- GLP-1, is only found in mammals.
- - Gastric inhibitory polypeptide (GIP), which is a potent stimulator of
- insulin secretion and a relatively poor inhibitor of gastric acid
- secretion.
- - Secretin, which stimulates formation of NaHCO(3)-rich pancreatic juice and
- secretion of NaHCO(3)-rich bile as well as inhibiting HCl production by the
- stomach.
- - Vasoactive intestinal peptide (VIP), which causes vasodilatation, lowers
- arterial blood pressure, stimulates myocardial contractility, increases
- glycogenolysis and relaxes some smooth muscles.
- - Peptide PHI-27, a vasodilator peptide which is coded by the same precursor
- protein as that of VIP.
- - Growth hormone-releasing factor (GRF) (also known as somatoliberin), which
- is released by the hypothalamus and acts on the adenohypophyse to stimulate
- the secretion of growth hormone.
- - Pituitary adenylate cyclase activating polypeptide (PACAP) [3].
- - Helospectin (exendin-1), helodermin (exendin-2), exendin-3, and exendin-4
- from the venom of gila monsters. The exendins are peptides with a VIP/
- secretin biological activity [4].
- - A peptide produced by the X-cells of the islets of ratfish pancreas [5].
-
- As a pattern for this family of peptides (which are from 30 to 45 amino acid
- residues long), we used the more or less conserved first ten positions of the
- N-terminal as well as a conserved hydrophobic residue in position 23.
-
- -Consensus pattern: [YH]-[STAVGD]-[DEQ]-[AGF]-[LIVSTE]-[FYLR]-x-[DENSTA](2)-
- [LIVMFYG]-x(12)-[LIV]
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: Crithidia fasciculata DNA
- topoisomerase II.
- -Last update: October 1993 / Pattern and text revised.
-
- [ 1] Mutt V.
- Ann. N.Y. Acad. Sci. 527:1-19(1988).
- [ 2] Bataille D., Blache P., Mercier F., Jarrousse C., Kervran A., Dufour M.,
- Mangeat P., Dubrasquet M., Mallat A., Lotersztajn S., Pavoine C.,
- Pecker F.
- Ann. N.Y. Acad. Sci. 527:169-185(1988).
- [ 3] Miyata A., Arimura A., Dahl R.R., Minamino N., Uehara A., Jiang A.,
- Culler M.D., Coy D.H.
- Biochem. Biophys. Res. Commun. 164:567-574(1989).
- [ 4] Eng J., Kleinman W.A., Singh L., Singh G., Raufman J.-P.
- J. Biol. Chem. 267:7402-7405(1992).
- [ 5] Conlon J.M., Dafgard E., Falkmer S., Thim L.
- Biochem. J. 245:851-855(1987).
-