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- * Gastrin / cholecystokinin family signature *
- **********************************************
-
- Gastrin and cholecystokinin (CCK) [1,2] are structurally and functionally
- related peptide hormones that function as hormonal regulators of various
- digestive processes and feeding behaviors . They are known to induce gastric
- secretion, stimulate pancreatic secretion, increase blood circulation and
- water secretion in the stomach and intestine, and stimulate smooth muscle
- contraction. Originally found in the gut, these hormones have since been
- shown to be present in various parts of the nervous system. Like many other
- active peptides they are synthesized as larger protein precursors that are
- enzymatically converted to their mature forms. They are found in several
- molecular forms due to tissue-specific post-translational processing. A
- number of other peptides are known to belong to the same family:
-
- - Caerulein [3], an amphibian skin peptide, with a biological activity
- similar to that of CCK or gastrin. There are different types of caerulein
- precursors [4] in which a single or up to four copies of the peptide are
- present.
- - Leukosulfakinin I and II (LSK) [5,6] are peptides, isolated from cockroach,
- that change the frequency and amplitude of contractions of the hindgut.
- - Drosulfakinins I and II [7] are putative CCK-homologs from Drosophila.
- Those two peptides are part of a precursor sequence that was isolated
- using a probe based on the sequence of CCK and LSK.
- - A chicken antrum peptide [8] which is a potent stimulus of avian gastric
- acid but not of pancreatic secretion.
- - Cionin [9], a neuropeptide from the protochordate Ciona intestinalis.
-
- The biological activity of gastrin and CCK is associated with the last five C-
- terminal residues. One or two positions downstream, there is a conserved
- sulfated tyrosine residue. The signature pattern developed for this family of
- peptides includes the biologically active C-terminal sequence as well as the
- sulfated tyrosine.
-
- -Consensus pattern: Y-x(0,1)-[GD]-[WH]-M-[DR]-F
- [Y is sulfated]
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
-
- -Note: the residues in positions 4 and 6 of the pattern are respectively Trp
- and Asp in vertebrate peptides, and His and Arg in insect peptides.
-
- -Last update: April 1990 / Text revised.
-
- [ 1] Concise Encyclopedia Biochemistry, Second Edition, Walter de Gruyter,
- Berlin New-York (1988).
- [ 2] Cholecystokinin.
- Ann. N.Y. Acad. Sci. Volume 448, (1985).
- [ 3] Erspamer V., Falconieri Erspamer G., Mazzanti G., Endean R.
- Comp. Biochem. Physiol. 77C:99-108(1984).
- [ 4] Richter K., Egger R., Kreil G.
- J. Biol. Chem. 261:3676-3680(1986).
- [ 5] Nachman R.J., Holman G.M., Haddon W.F., Ling N.
- Science 234:71-73(1986).
- [ 6] Nachman R.J., Holman G.M., Cook B.J., Haddon W.F., Ling N.
- Biochem. Biophys. Res. Commun. 140:357-364(1986).
- [ 7] Nichols R., Schneuwly S.A., Dixon J.E.
- J. Biol. Chem. 263:12167-12170(1988).
- [ 8] Dimaline R., Young J., Gregory H.
- FEBS Lett. 205:318-322(1986).
- [ 9] Johnsen A.H., Rehfeld J.F.
- J. Biol. Chem. 265:3054-3058(1990).
-