Photoaffinity labelling of gonadotropin releasing hormone binding sites in human epithelial ovarian carcinomata.
A photoaffinity labelled derivative of [D-Lys6]-GnRH was prepared with a bifunctional photolabile reagent (4-azidobenzoyl)-N-hydroxysuccinimide. In rat pituitary membranes, this analog retained high binding affinity (Ka = 0.12 x 10(9) M-1) consistent with a single class of receptors. The analog was iodinated and used for the identification of GnRH binding sites in human epithelial ovarian carcinomata. By sodium dodecyl sulfate electrophoresis in 10% polyacrylamide gel the presence of two labelled components could be demonstrated: a high molecular weight component of 63,200 and a smaller component of 46,000. Competition experiments with unlabelled ligand suggest that it is the high molecular weight component which specifically binds GnRH.
Pahwa
G S
GS
Department of Obstetrics and Gynecology, Medical University of Lübeck, F.R.G.
Vollmer
G
G
Knuppen
R
R
Emons
G
G
D000230:Adenocarcinoma / Q000378:metabolism; D000345:Affinity Labels / Q000378:metabolism*; D001386:Azides / Q000138:chemical synthesis / Q000378:metabolism*; D002277:Carcinoma / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D008970:Molecular Weight; D010051:Ovarian Neoplasms / Q000378:metabolism*; D011966:Receptors, LHRH / Q000302:isolation & purification / Q000378:metabolism*
D000345:Affinity Labels; D001386:Azides; D011966:Receptors, LHRH; D007987:Gonadotropin-Releasing Hormone; C031737:LHRH, N-epsilon-azidobenzoyl-Lys(6)-