Isolation of a murine glucose-dependent insulinotropic polypeptide (GIP) cDNA from a tumor cell line (STC6-14) and quantification of glucose-induced increases in GIP mRNA

• Published in: Biochimica et biophysica acta Vol. 1308; no. 2; pp. 111 - 113
• Main Authors: Schieldrop, P J, Gelling, R W, Elliot, R, Hewitt, J, Kieffer, T J, McIntosh, C H, Pederson, R A
• Format: Journal Article
• Language: English
• Published: Netherlands 14.08.1996
• Subjects: Amino Acid Sequence; Animals; Base Sequence; DNA, Complementary - genetics; Dose-Response Relationship, Drug; Gastric Inhibitory Polypeptide - biosynthesis; Gastric Inhibitory Polypeptide - genetics; Gene Expression Regulation; Glucose - pharmacology; Mice; Molecular Sequence Data; Polymerase Chain Reaction; Protein Precursors - genetics; RNA, Messenger - analysis; RNA, Neoplasm - analysis; Sequence Homology, Amino Acid; Tumor Cells, Cultured
• ISSN: 0006-3002; 0167-4781
• DOI: 10.1016/0167-4781(96)00103-0

A 537 base pair cDNA clone for murine GIP has been isolated. The elucidated sequence encodes an open reading frame of 432 base pairs which codes for a 144 amino acid precursor. Murine GIP is predicted to differ from the human hormone by three amino acid substitutions: arginine for histidine at position 18, arginine for lysine at position 30 and serine for lysine at position 34. GIP mRNA levels in STC6-14 cells incubated in the presence of varying glucose concentrations was investigated using a competitive-PCR method. In the presence of a 5-mM glucose stimulus, 1 x 10(5) GIP cells were found to contain 3.9 +/- 0.59 amol of GIP mRNA while the same number of cells contained 11.6 +/- 1.4 amol when subjected to a high (25 mM) glucose stimulus.