A luteinizing hormone receptor with a severely truncated cytoplasmic tail (LHR-ct628) desensitizes to the same degree as the full-length receptor

• Published in: The Journal of biological chemistry Vol. 268; no. 3; pp. 1723 - 1728
• Main Authors: XI ZHU, GUDERMANN, T, BIRNBAUMER, M, BIRNBAUMER, L
• Format: Journal Article
• Language: English
• Published: Bethesda, MD American Society for Biochemistry and Molecular Biology 25-01-1993
• Subjects: Adenylyl Cyclases - metabolism; Amino Acid Sequence; Animals; Base Sequence; Biological and medical sciences; Cell receptors; Cell structures and functions; Chorionic Gonadotropin - pharmacology; cytoplasm; desensitization; domains; Enzyme Activation - drug effects; Fundamental and applied biological sciences. Psychology; Gene Expression; Hormone receptors. Growth factor receptors. Cytokine receptors. Prostaglandin receptors; L Cells - metabolism; luteinizing hormone; Luteinizing Hormone - pharmacology; Mice; Molecular and cellular biology; Molecular Sequence Data; Mutagenesis; Phosphorylation; pigs; Polymerase Chain Reaction; Rats; receptors; Receptors, LH - chemistry; Receptors, LH - genetics; Receptors, LH - physiology; requirements; Transfection; Adenylate cyclase; Vertebrata; Mammalia; Desensitization; Transfection; Structure activity relation; Mouse; Enzyme; Rodentia; Mutation; LH; Hormonal receptor
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1016/S0021-9258(18)53912-0

The wild type murine luteinizing hormone (mLH) receptor, which in its mature form is predicted to be a protein of 674 amino
acids (mLHR), and an artificially mutated form lacking the last 46 amino acids (mLHR-ct628) were stably expressed in murine
L cells. Both forms stimulated adenylyl cyclase and underwent rapid desensitization. The mutation removed 1 tyrosine, 2 threonines,
and 6 serines from the receptor. The results indicate that none of these potential phosphorylation sites participates in either
adenylyl cyclase stimulation or receptor desensitization. Our results with the mLHR-ct628 (carboxyl-terminal amino acid sequence
CCKHRAEL) differ from those reported recently for the essentially identically mutated rat LHR that lacks the last 43 amino
acids (rLHR-ct631 with carboxyl-terminal amino acid composition CCKRRAELYRR). This 43-amino acid truncation was described
to have the effect of preventing hormone-induced desensitization. While the reasons for the discrepant results are not known,
our results do not support the proposal for a participatory role of the extreme carboxyl terminus of the receptor in its desensitization.