Purification of an endothelin receptor from human placenta.
We have identified an endothelin (ET) binding protein on the membranes of human placenta and purified it to homogeneity. It is a polypeptide with an apparent Mol. Wt. of 40,000 and is a major protein to be labeled by cross-linking with either 125I-ET-1, -2, or -3. Binding studies with Scatchard analysis indicated the presence of a single class, high-affinity binding site with Kds of 57 pM, 480 pM and 40 nM for 125I-labeled ET-1, ET-2 and ET-3, respectively. These results suggest that the 40K protein is a major ET receptor in placenta and, most likely, can bind differentially to ET-1, ET-2 and ET-3.
Wada
K
K
Department of Molecular Genetics, Nippon Roche Research Center, Kamakura, Japan.
Tabuchi
H
H
Ohba
R
R
Satoh
M
M
Tachibana
Y
Y
Akiyama
N
N
Hiraoka
O
O
Asakura
A
A
Miyamoto
C
C
Furuichi
Y
Y
D000345:Affinity Labels; D002846:Chromatography, Affinity; D003432:Cross-Linking Reagents; D004591:Electrophoresis, Polyacrylamide Gel; D016232:Endothelins; D004730:Endothelium, Vascular / Q000378:metabolism*; D005260:Female; D006801:Humans; D010455:Peptides / Q000378:metabolism*; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D011956:Receptors, Cell Surface / Q000302:isolation & purification*; D017466:Receptors, Endothelin
D000345:Affinity Labels; D003432:Cross-Linking Reagents; D016232:Endothelins; D010455:Peptides; D011956:Receptors, Cell Surface; D017466:Receptors, Endothelin