Cloning and characterization of gastrin receptor from ECL carcinoid tumor of Mastomys natalensis.
We report here the cDNA cloning of a putative gastrin receptor from enterochromaffin-like (ECL) carcinoid tumor of Mastomys natalensis. For this study, we used the polymerase chain reaction technique to amplify transmembrane domain sequences related to rat pancreatic cholecystokinin (CCK)-A receptor from the ECL tumor cDNA library. The amino acid sequence deduced from the cloned cDNA showed 85.7% and 49.0% identity to canine parietal cell gastrin receptor and rat pancreatic CCK-A receptor, respectively. Ligand binding studies using COS-7 cells transfected with the cDNA showed the same binding specificity for gastrin and CCK-8 as the gastrin receptor on the Mastomys carcinoid tumor membrane. Both gastrin and CCK-8 elevated free cytosolic calcium concentration in COS-7 cells expressing the cloned receptor. RNA blot analysis revealed the expression of the gastrin receptor in both Mastomys stomach and brain.
Nakata
H
H
Department of Medicine, Kobe University School of Medicine, Japan.
Matsui
T
T
Ito
M
M
Taniguchi
T
T
Naribayashi
Y
Y
Arima
N
N
Nakamura
A
A
Kinoshita
Y
Y
Chihara
K
K
Hosoda
S
S
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002118:Calcium / Q000378:metabolism; D002276:Carcinoid Tumor / Q000378:metabolism*; D003001:Cloning, Molecular; D004247:DNA / Q000737:chemistry / Q000235:genetics; D004285:Dogs; D005260:Female; D005755:Gastrins / Q000378:metabolism / Q000494:pharmacology; D008969:Molecular Sequence Data; D009115:Muridae; D010179:Pancreas / Q000737:chemistry; D010295:Parietal Cells, Gastric / Q000737:chemistry; D051381:Rats; D011949:Receptors, Cholecystokinin / Q000737:chemistry / Q000235:genetics*; D012689:Sequence Homology, Nucleic Acid; D012844:Sincalide / Q000494:pharmacology; D013274:Stomach Neoplasms / Q000378:metabolism*; D014162:Transfection
D005755:Gastrins; D011949:Receptors, Cholecystokinin; D004247:DNA; D012844:Sincalide; D002118:Calcium