Multiple gastrin-releasing peptide gene-associated peptides are produced by a human small cell lung cancer line.
Products of the gastrin-releasing peptide gene were isolated from culture medium supernatant of a small cell lung cancer line, NCI-H345, by several (high performance liquid chromatography) HPLC steps. The column eluates were monitored by immunoassay and absorbance profiles. Gastrin-releasing peptide was identified in HPLC eluates by a specific radioimmunoassay. Two carboxyl-terminal gastrin-releasing peptide gene-associated peptides were identified by a radioimmunoassay specific for their predicted carboxyl terminus. The amino termini of these two peptides were determined by microsequence analysis. The shorter peptide was revealed to be a fragment of the larger peptide. Expression of an alternate mRNA was shown by isolation and characterization of a novel tetradecapeptide. Amino acid analysis, microsequence analysis, and mass spectral analysis confirmed that the structure was Ser-Leu-Leu-Gln-Val-Leu-Asn-Val-Lys-Glu-Gly-Thr-Pro-Ser. This peptide represents the carboxyl terminus of a peptide resulting from alternate processing of gastrin releasing peptide mRNA. This mRNA contains a 19-base deletion, creating a frame shift. A radioiodinated synthetic analog of this peptide (Tyr-Leu-Val-Asp-Ser-Leu-Leu-Gln-Val-Leu-Asn-Val-Lys-Glu-Gly-Thr-Pro-Ser ) bound specifically to a small cell cancer line with high affinity, suggesting possible biological activity of the isolated peptide.
Reeve
J R
JR
Center for Ulcer Research and Education, UCLA School of Medicine, Veterans Administration Wadsworth Medical Center 90073.
Cuttitta
F
F
Vigna
S R
SR
Heubner
V
V
Lee
T D
TD
Shively
J E
JE
Ho
F J
FJ
Fedorko
J
J
Minna
J D
JD
Walsh
J H
JH
D000595:Amino Acid Sequence; D018288:Carcinoma, Small Cell / Q000235:genetics; D002460:Cell Line; D002851:Chromatography, High Pressure Liquid; D003001:Cloning, Molecular; D004273:DNA, Neoplasm / Q000235:genetics; D019886:Gastrin-Releasing Peptide; D005768:Gastrointestinal Hormones / Q000235:genetics*; D005796:Genes; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000302:isolation & purification; D010455:Peptides / Q000235:genetics*; D021382:Protein Sorting Signals / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics
D004273:DNA, Neoplasm; D005768:Gastrointestinal Hormones; D010446:Peptide Fragments; D010455:Peptides; D021382:Protein Sorting Signals; D012333:RNA, Messenger; D019886:Gastrin-Releasing Peptide