Patterns of prohormone processing. Order revealed by a new procholecystokinin-derived peptide

J Biol Chem. 1992 Jan 25;267(3):1517-21.

Abstract

An 83-amino acid cholecystokinin peptide with a sulfated tyrosine and an amidated carboxyl terminus (CCK-83) was purified from human intestinal mucosa. The purified peptide was chemically characterized, and its bioactivity was compared to CCK-8. Several post-translational processing steps such as cleavage at basic residues, sulfation, and amidation are necessary to form biologically active cholecystokinin from its nascent prepropeptide. The discovery of CCK-83 gives new insight into the order of preprohormone processing. The processing of prepro-CCK appears to be in the order of: 1) signal peptidase cleavage, 2) tyrosine sulfation, 3) cleavage after a carboxyl-terminal pair of basic residues, 4) carboxypeptidase B-like cleavage of these basic residues, 5) amidation (which results in the formation of CCK-83), and 6) cleavage at monobasic residues by endopeptidases (which results in the smaller molecular forms of cholecystokinin). The characterization of biologically active CCK-83 with a sulfated tyrosine and an amidated carboxyl terminus establishes the site of signal peptidase action and suggests an order of post-translational modifications that give rise to the various molecular forms of cholecystokinin.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Amino Acids / analysis
  • Amylases / metabolism
  • Animals
  • Cholecystokinin / genetics*
  • Cholecystokinin / isolation & purification
  • Cholecystokinin / pharmacology
  • Chromatography, High Pressure Liquid
  • Chromatography, Ion Exchange
  • Endopeptidases / metabolism*
  • Humans
  • In Vitro Techniques
  • Intestinal Mucosa / metabolism*
  • Male
  • Membrane Proteins*
  • Molecular Sequence Data
  • Pancreas / drug effects
  • Pancreas / enzymology
  • Peptide Fragments / chemistry
  • Peptide Mapping
  • Protein Precursors / genetics*
  • Protein Precursors / isolation & purification
  • Protein Precursors / pharmacology
  • Protein Processing, Post-Translational*
  • Protein Sorting Signals / genetics
  • Protein Sorting Signals / metabolism
  • Rats
  • Rats, Inbred Strains
  • Serine Endopeptidases*
  • Sincalide / pharmacology

Substances

  • Amino Acids
  • Membrane Proteins
  • Peptide Fragments
  • Protein Precursors
  • Protein Sorting Signals
  • procholecystokinin
  • Cholecystokinin
  • Amylases
  • Endopeptidases
  • Serine Endopeptidases
  • type I signal peptidase
  • Sincalide