A 64 kDa protein is a candidate for a thyrotropin-releasing hormone receptor in prolactin-producing rat pituitary tumor cells (GH4C1 cells).
A thyrotropin-releasing hormone (TRH) binding protein of 64 kDa has been identified by covalently crosslinking [3H]TRH to GH4C1 cells by ultraviolet illumination. The crosslinkage of [3H]TRH is UV-dose dependent and is inhibited by an excess of unlabeled TRH. A 64 kDa protein is also detected on immunoblots using an antiserum raised against GH4C1 cell surface epitopes. In a closely related cell line (GH12C1) which does not bind [3H]TRH, the 64 kDa protein cannot be demonstrated by [3H]TRH crosslinking nor by immunoblotting. These findings indicate that the 64 kDa protein is a candidate for a TRH-receptor protein in GH4C1 cells.
Wright
M
M
Institute of Medical Biochemistry, University of Oslo, Norway.
Høgset
A
A
Alestrøm
P
P
Gautvik
K M
KM
D000345:Affinity Labels; D000818:Animals; D002462:Cell Membrane / Q000032:analysis; D004591:Electrophoresis, Polyacrylamide Gel; D015151:Immunoblotting; D008970:Molecular Weight; D010777:Photochemistry; D010911:Pituitary Neoplasms / Q000032:analysis* / Q000378:metabolism; D011388:Prolactin / Q000096:biosynthesis*; D051381:Rats; D017981:Receptors, Neurotransmitter / Q000032:analysis* / Q000378:metabolism; D018025:Receptors, Thyrotropin-Releasing Hormone; D013973:Thyrotropin-Releasing Hormone / Q000378:metabolism; D014407:Tumor Cells, Cultured; D014466:Ultraviolet Rays
D000345:Affinity Labels; D017981:Receptors, Neurotransmitter; D018025:Receptors, Thyrotropin-Releasing Hormone; D013973:Thyrotropin-Releasing Hormone; D011388:Prolactin