Pivotal role for the cytoplasmic carboxyl-terminal tail of a nonmammalian gonadotropin-releasing hormone receptor in cell surface expression, ligand binding, and receptor phosphorylation and internalization

被引:71
作者
Blomenröhr, M [1 ]
Heding, A [1 ]
Sellar, R [1 ]
Leurs, R [1 ]
Bogerd, J [1 ]
Eidne, KA [1 ]
Willars, GB [1 ]
机构
[1] Univ Utrecht, Dept Expt Zool, NL-3584 CH Utrecht, Netherlands
关键词
D O I
10.1124/mol.56.6.1229
中图分类号
R9 [药学];
学科分类号
1007 ;
摘要
The gonadotropin-releasing hormone receptor (GnRH-R) of the African catfish couples to phospholipase C and belongs to the large family of G protein-coupled receptors. We recently demonstrated that removal of the carboxyl-terminal tail (S331-Q379) from the catfish GnRH-R results in a loss of agonist binding; the current study sought to define more precisely the role of this region in receptor function. Progressive truncations of the carboxyl-terminal tail decreased cell surface expression detected by either enzyme-linked immunosorbent assay or agonist-binding. The two most truncated receptors (stop331 and stop337) showed no binding but were detected at the cell surface by enzyme-linked immunosorbent assay. All receptors able to bind agonist were also able to activate phospholipase C. The catfish GnRH-R was phosphorylated after agonist-occupation and use of truncated mutants showed this phosphorylation to be within the carboxyl-terminal tail. Furthermore, studies with S356A, S363A and SS356,363AA mutant receptors demonstrated that Ser363 is a major site of agonist-induced phosphorylation. The absence of this phospho-acceptor site markedly impaired agonist- mediated receptor internalization. In addition, both, Ser363 and the last 12 residues of the tail (not containing Ser363) were shown to be important for beta-arrestin-dependent internalization. These observations are relevant to the regulatory function of the carboxyl-terminal tail of G protein-coupled receptors in general and are particularly intriguing given the absence of this region in mammalian GnRH-Rs.
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页码:1229 / 1237
页数:9
相关论文
共 40 条
[1]   Mutations of the conserved DRS motif in the second intracellular loop of the gonadotropin-releasing hormone receptor affect expression, activation, and internalization [J].
Arora, KK ;
Cheng, ZY ;
Catt, KJ .
MOLECULAR ENDOCRINOLOGY, 1997, 11 (09) :1203-1212
[2]   EFFECTS OF 2ND INTRACELLULAR LOOP MUTATIONS ON SIGNAL-TRANSDUCTION AND INTERNALIZATION OF THE GONADOTROPIN-RELEASING-HORMONE RECEPTOR [J].
ARORA, KK ;
SAKAI, A ;
CATT, KJ .
JOURNAL OF BIOLOGICAL CHEMISTRY, 1995, 270 (39) :22820-22826
[3]  
BENYA RV, 1993, J BIOL CHEM, V268, P20285
[4]   INOSITOL TRISPHOSPHATE AND CALCIUM SIGNALING [J].
BERRIDGE, MJ .
NATURE, 1993, 361 (6410) :315-325
[5]   Differences in structure-function relations between nonmammalian and mammalian gonadotropin-releasing hormone receptors [J].
Blomenrohr, M ;
Bogerd, J ;
Leurs, R ;
Schulz, RW ;
Tensen, CP ;
Zandbergen, MA ;
Goos, HJT .
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 1997, 238 (02) :517-522
[6]  
Bohm SK, 1997, BIOCHEM J, V322, P1
[7]   Switching of the coupling of the beta(2)-adrenergic receptor to different G proteins by protein kinase A [J].
Daaka, Y ;
Luttrell, LM ;
Lefkowitz, RJ .
NATURE, 1997, 390 (6655) :88-91
[8]  
Ferguson S S, 1998, Adv Pharmacol, V42, P420
[9]   ROLE OF PHOSPHORYLATION IN AGONIST-PROMOTED BETA(2)-ADRENERGIC RECEPTOR SEQUESTRATION - RESCUE OF A SEQUESTRATION-DEFECTIVE MUTANT RECEPTOR BY BETA-ARK1 [J].
FERGUSON, SSG ;
MENARD, L ;
BARAK, LS ;
KOCH, WJ ;
COLAPIETRO, AM ;
CARON, MG .
JOURNAL OF BIOLOGICAL CHEMISTRY, 1995, 270 (42) :24782-24789
[10]   G-protein-coupled receptor regulation: Role of G-protein-coupled receptor kinases and arrestins [J].
Ferguson, SSG ;
Barak, LS ;
Zhang, J ;
Caron, MG .
CANADIAN JOURNAL OF PHYSIOLOGY AND PHARMACOLOGY, 1996, 74 (10) :1095-1110