Quantitation and characterization of peptides from the C-terminal flanking region of rat and bovine preprotachykinins

• Published in: Journal of neurochemistry Vol. 53; no. 6; p. 1871
• Main Authors: McGregor, G P, Kage, R, Thim, L, Conlon, J M
• Format: Journal Article
• Language: English
• Published: England 01.12.1989
• Subjects: Amino Acid Sequence; Animals; Brain Chemistry; Cattle; Corpus Striatum - analysis; Digestive System - analysis; Male; Molecular Sequence Data; Organ Specificity; Peptide Fragments - isolation & purification; Protein Precursors - isolation & purification; Rats; Rats, Inbred Strains; Tachykinins - isolation & purification
• ISSN: 0022-3042
• DOI: 10.1111/j.1471-4159.1989.tb09255.x

Sequence analysis of cDNAs has shown that the biosynthetic precursors of substance P (alpha-, beta-, and gamma-preprotachykinins) contain a common amino acid sequence in the C-terminal flanking region that has not been conserved between species. Antisera have been raised against the synthetic peptide Tyr-Glu-Arg-Ser-Ala-Met-Gln-Asn-Tyr-Glu, which represents rat beta-preprotachykinin-(117-126)-peptide, and used in radioimmunoassays. Antiserum R50 reacted strongly with C-flanking peptides in extracts of rat and bovine tissues whereas antiserum GP-4 reacted only with the rat peptides. The primary structure of the predominant molecular form of preprotachykinin C-flanking peptide in an extract of bovine corpus striatum was established as: Ala-Leu-Asn-Ser-Val5-Ala-Tyr-Glu-Arg-Ser10-Val-Met-Gln-Asp-Tyr1 5-Glu. This sequence represents beta-preprotachykinin-(111-126)-peptide which is equivalent to gamma-preprotachykinin-(96-111)-peptide. A C-flanking peptide with similar chromatographic properties was identified in extracts of rat brain and gut together with a second immunoreactive component that may represent a fragment or a posttranslationally modified variant. A peptide corresponding to the 37-amino-acid residue C-flanking peptide derived from alpha-preprotachykinin was not detected in the extracts as expected from the known low abundance of alpha-preprotachykinin mRNA in rat brain and gut.