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.
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.
Schieldrop
P J
PJ
Department of Physiology, University of British Columbia, Vancouver, Canada.
Gelling
R W
RW
Elliot
R
R
Hewitt
J
J
Kieffer
T J
TJ
McIntosh
C H
CH
Pederson
R A
RA
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018076:DNA, Complementary / Q000235:genetics; D004305:Dose-Response Relationship, Drug; D005749:Gastric Inhibitory Polypeptide / Q000096:biosynthesis* / Q000235:genetics; D005786:Gene Expression Regulation; D005947:Glucose / Q000494:pharmacology*; D051379:Mice; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011498:Protein Precursors / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis; D012334:RNA, Neoplasm / Q000032:analysis; D017386:Sequence Homology, Amino Acid; D014407:Tumor Cells, Cultured
D018076:DNA, Complementary; D011498:Protein Precursors; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D005749:Gastric Inhibitory Polypeptide; D005947:Glucose