Molecular cloning and functional expression of the human gallbladder cholecystokinin A receptor.
Through binding to cholecystokinin (CCK) A receptors, CCK is an important physiologic regulator of both gallbladder contraction and pancreatic enzyme secretion. In this work, we have used a combination of hybridization screening of a cDNA library and polymerase chain reaction to clone a 2.1 kb cDNA which encodes the human gallbladder CCKA receptor. Nucleotide sequence analysis revealed an open reading frame encoding a 428 amino acid protein, with seven putative transmembrane domains and a high degree of homology with the rat CCKA receptor. COS cells transfected with this cDNA clone bound CCK-8 and L-364,718 with high affinities appropriate for the CCKA receptor, and exhibited a transient increase in intracellular calcium in response to CCK. This should provide an important resource for the analysis of the role of this receptor in human physiology and pathophysiology.
Center for Basic Research in Digestive Diseases, Mayo Clinic, Rochester, MN 55905.
C D
CD
Ulrich
I
I
Ferber
E
E
Holicky
E
E
Hadac
G
G
Buell
L J
LJ
Miller
D000595:Amino Acid Sequence; D000818:Animals; D001667:Binding, Competitive; D002478:Cells, Cultured; D003001:Cloning, Molecular; D004247:DNA; D005704:Gallbladder / Q000378:metabolism*; D006801:Humans; D008969:Molecular Sequence Data; D011949:Receptors, Cholecystokinin / Q000235:genetics* / Q000378:metabolism; D015290:Second Messenger Systems; D017386:Sequence Homology, Amino Acid; D014162:Transfection
D011949:Receptors, Cholecystokinin; D004247:DNA