Radiation inactivation (target size analysis) of the gonadotropin-releasing hormone receptor: evidence for a high molecular weight complex.
In the present study we used radiation inactivation (target size analysis) to measure the functional mol wt of the GnRH receptor while it is still a component of the plasma membrane. This technique is based on the observation that an inverse relationship exists between the dose-dependent inactivation of a macromolecule by ionizing radiation and the size of that macromolecule. This method demonstrates a mol wt of 136,346 +/- 8,120 for the GnRH receptor. This estimate is approximately twice that obtained (60,000) by photoaffinity labeling with a radioactive GnRH analog followed by electrophoresis under denaturing conditions and, accordingly, presents the possibility that the functional receptor consists of a high mol wt complex in its native state. The present studies indicate that the GnRH receptor is either a single weight class of protein or several closely related weight classes, such as might occur due to protein glycosylation.
Conn
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Venter
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D000818:Animals; D002462:Cell Membrane / Q000378:metabolism / Q000528:radiation effects; D005260:Female; D008970:Molecular Weight; D010902:Pituitary Gland / Q000378:metabolism / Q000528:radiation effects / Q000648:ultrastructure; D010906:Pituitary Hormone-Releasing Hormones / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D011956:Receptors, Cell Surface / Q000528:radiation effects*; D013997:Time Factors
D010906:Pituitary Hormone-Releasing Hormones; D011956:Receptors, Cell Surface