Processing of mammalian preprogastrin-releasing peptide.
The processing of preprogastrin-releasing peptide in mammalian tissues and in cultured cells takes place at discrete sites (Figure 6). Signal peptidase cleaves away the signal peptide from the amino terminus of gastrin-releasing peptide. An exopeptidase activity may remove dipeptides from the amino terminus. The amidation site (not shown in Fig. 6; see Fig. 2) has the same general sequence (Gly-Lys-Lys) seen for other amidated peptides. Cleavage after single basic residues yields gene-related products from Form I or II preproGRP. A unique non-basic cleavage yields a gene-related product from Form III preproGRP. The processing that occurs to form GRP, GRP, and GRP gene-related peptides is shown in Figure 7. ProGRP is cleaved by a series of enzymes to form GRP with an amidated carboxyl-terminal methionine (indicated by an asterisk in Fig. 7). GRP is cleaved to form the decapeptide GRP. The carboxyl-terminal flanking peptides of all three mRNA translation products are cleaved to form several gastrin-releasing peptide gene-related products. Knowledge of the processing of gastrin-releasing peptide and its gene-related products will allow synthesis of duplicates of the stored forms of these peptides, which can then be used for biological testing.
Reeve
J R
JR
University of California, Los Angeles, School of Medicine.
Cuttitta
F
F
Vigna
S R
SR
Shively
J E
JE
Walsh
J H
JH
D000595:Amino Acid Sequence; D000818:Animals; D001839:Bombesin / Q000235:genetics; D006801:Humans; D008322:Mammals; D008969:Molecular Sequence Data; D010455:Peptides / Q000235:genetics*; D011498:Protein Precursors / Q000235:genetics*; D011499:Protein Processing, Post-Translational
D010455:Peptides; D011498:Protein Precursors; C047897:gastrin-releasing peptide precursor; D001839:Bombesin