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(Hypertension. 1995;25:726-730.)
© 1995 American Heart Association, Inc.

Articles

Mapping of G Protein Coupling Sites of the Angiotensin II Type 1 Receptor

Heigoro Shirai; Katsunobu Takahashi; Toshiaki Katada; Tadashi Inagami

From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tenn (H.S., T.I.); Department of Life Science, Tokyo Institute of Technology, Yokohama, Japan (K.T.); and Department of Physiological Chemistry, Faculty of Pharmaceutical Sciences, University of Tokyo (Japan) (T.K.).

Correspondence to Tadashi Inagami, PhD, Department of Biochemistry, Vanderbilt University School of Medicine, 23rd Ave S at Pierce Ave, LH663, Nashville, TN 37232.

	Abstract

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Abstract Angiotensin II type 1 (AT₁) receptors have been identified in a wide variety of tissues, including the kidney, liver, adrenal gland, cardiovascular system, and brain. AT₁ receptors also mediate complex signaling mechanisms that elicit a diversity of specific physiological effects. The rat AT_1A receptor has seven transmembrane domains and couples with three distinct G proteins: G_q, G_i, and G_o. But it is unknown which domains of AT_1A couple with and activate each type of G protein. To identify the domains responsible for the activation of various types of G protein, we studied the effect of five different synthetic peptides representing different domains of cytosolic segments of the rat AT_1A receptor on the binding of the ³⁵S-labeled stable analogue of GTP, GTPS. Peptides P-3, which is located in the N-terminal region of the putative third intracellular loop of AT_1A (residues 216 through 230), and P-5 (residues 306 through 320), corresponding to the N-terminal region of the C-terminal tail, were found to activate purified G_i1, G_i2, and G_o proteins. These results indicate that not only the third cytosolic loop but also the C-terminal cytosolic domain of AT_1A is important for G_i1, G_i2, and G_o protein coupling and activation.

Key Words: angiotensin II • receptors, angiotensin • G protein • signal transduction • rats

	Introduction

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Angiotensin II (Ang II) activates G_q, G_i, and G_o proteins through the Ang II type 1 (AT₁) receptor.^{1 2 3} The agonist-bound receptor promotes the exchange of GT_P for GDP on the -subunit of a G protein. The GTP-G_q complex subsequently stimulates phospholipase C-ß^{4 5} ; G_i protein inhibits adenylate cyclase⁶ ; G_o protein inhibits neuronal -conotoxin GVIA (CTX)–sensitive calcium channels^{7 8} ; and pertussis toxin–sensitive G proteins open L-type Ca²⁺ channels.⁹ The intrinsic GTPase activity of the -subunit terminates the activation cycle by hydrolyzing GTP to inactive GDP. In studies of ß-adrenergic receptors, the role and mode of G protein action were demonstrated with a functionally active, reconstituted system composed of purified components of the signal transduction chain from several different sources.^{10 11}

Ang II receptors from bovine adrenal,¹² rat aortic vascular smooth muscle cells (VSMCs),¹³ and human sources^{14 15} have been cloned and sequenced. They have a degree of sequence homology with other G protein–linked receptors and share a basic structural motif. Based on the electron diffraction data of Henderson and Unwin¹⁶ on bacteriorhodopsin and the hydropathy profile for rhodopsin,¹⁷ a structural model of this receptor family was constructed that consists of seven hydrophobic transmembrane-spanning helical regions connected by extracellular and intracellular hydrophilic loops. The rat AT_1A receptor consists of 359 amino acid residues. Functional domains involved in receptor–G protein interactions have been explored by site-directed mutagenesis.¹⁸ To further explore the receptor–G protein coupling domains, we prepared synthetic peptides corresponding to the regions of the intracellular loops of the AT_1A receptor that are highly conserved among AT₁ receptors from various species and tested their ability to compete with intact AT_1A for interaction with purified heterotrimeric G_i1, G_i2, and G_o. Unlike methods based on mutagenesis in which artifacts in structure and function cannot be excluded, the use of synthetic peptides allows one to perform experiments with unmodified components. Our results presented here made it possible to identify regions involved in the coupling of the AT₁ receptor with G_i and G_o proteins.

	Methods

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Reagents
[³⁵S]GTPS was purchased from DuPont-NEN. Filter membranes were purchased from Schleicher & Schuell. Other materials and reagents were purchased from Sigma Chemical Co or Fisher Scientific Co.

Cell Culture and Membrane Preparation
COS-7 cells were obtained from American Type Culture Collection. VSMCs were isolated from the thoracic aorta of Wistar-Kyoto rats as described previously.¹⁹ COS-7 cells and VSMCs (passages 7 through 15) were maintained in Dulbecco's modified Eagle's medium containing 10% fetal calf serum, 100 µg/mL streptomycin, and 100 U/mL penicillin in a humidified atmosphere at 37°C under 5% CO₂. Cells were washed three times with Hanks' balanced salt solution, scraped, and collected by centrifugation at 1500g for 5 minutes. The plasma membrane fraction was prepared by a published method.¹⁸ Plasma membranes were suspended in 25 mmol/L HEPES-NaOH buffer (pH 7.4) containing 120 µmol/L MgCl₂, 100 µmol/L EDTA, 5 µg/mL leupeptin, 5 µg/mL pepstatin A, and 40 µmol/L phenylmethylsulfonyl fluoride.

Synthetic Peptides and G Proteins
The peptides used in this study were synthesized by the solid-phase method and highly purified (95% to 99%) by high-performance liquid chromatography using a Nucleosil 5 C18 column eluted with a linear concentration gradient (0% to 60%) of CH₃CN containing 0.1% trifluoroacetic acid. The lyophilized synthetic peptide was dissolved in water. Heterotrimeric forms of G_i1, G_i2, and G_o proteins from bovine brain were purified to homogeneity.²⁰

GTPS Binding Assay
[³⁵S]GTPS binding promoted by synthetic peptides to 5 µg of membranes from COS-7 cells or VSMCs (100 mg/mL membrane) was measured in 25 mmol/L HEPES-NaOH buffer (pH 7.4) containing 120 µmol/L MgCl₂, 100 µmol/L EDTA, and 100 nmol/L [³⁵S]GTPS in the absence of phospholipids as described by Okamoto et al.²¹ [³⁵S]GTPS binding to 10 nmol/L purified heterotrimeric G proteins was measured by the same method. Briefly, membranes or G proteins were incubated with or without synthetic peptides in the buffer indicated above at 37°C for the indicated period. Incubations were terminated by addition of 10 vol ice-cold stopping buffer containing 100 mmol/L Tris-HCl (pH 8.0), 25 mmol/L MgCl₂, 100 mmol/L NaCl, and 20 µmol/L GTP. After materials were rapidly filtered through a nitrocellulose filter (pore size, 0.45 µm) and washed three times with the stopping buffer, the filter was counted in a liquid scintillation counter. GTPS binding to the synthetic peptides was negligible at 10 µmol/L peptide. The maximal binding of [³⁵S]GTPS to G proteins was measured in the presence of 1 µmol/L GTPS and 25 mmol/L Mg²⁺ at room temperature by the method of Northup et al²² as a positive control.

Statistics
Statistical analysis was carried out by one-way ANOVA followed by Duncan's new multiple range comparison.

	Results

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As shown in Fig 1, five peptides were synthesized corresponding to the conserved regions among AT₁ receptors from various species of the second and third cytoplasmic loops and the N-terminal segment of the cytosolic C-terminal tail of the rat AT_1A receptor. Each sequence consisted mainly of hydrophilic amino acids. The ability of each of the peptides to activate G proteins was tested with intact plasma membranes of COS-7 cells or VSMCs. Receptor-mediated G protein activation as reflected by the binding of the stable GTP analogue [³⁵S]GTPS was followed by measurement of specific binding of [³⁵S]GTPS.

View larger version (48K): [in this window] [in a new window]   Figure 1. Illustration shows amino acid sequence of rat angiotensin II type 1A receptor (from Murphy et al13 ) (amino acid residues 100 through 325). The synthesized peptide sequences are indicated by solid lines and designated as P-1 through P-5.

Effect of Peptides on GTPS Binding to G Proteins in Membranes
As shown in Fig 2, peptides P-2, P-3, and P-5 individually activated G proteins for GTPS binding in COS-7 cell membranes in a time- and concentration-dependent manner, suggesting that these peptides compete for receptor binding domains of the G proteins. The peptides P-1 and P-4 showed no effect up to 100 µmol/L. Peptides P-2, P-3, and P-5 also activated G proteins in VSMC membranes, and again, P-1 and P-4 showed no effect (data not shown).

View larger version (23K): [in this window] [in a new window]   Figure 2. Line graphs show effect of synthetic peptides with amino acid sequences of cytosolic loop regions of the rat angiotensin II type 1A (AT1A) receptor on COS-7 membrane G proteins. A, Time course of GTPS binding to G proteins in COS-7 cell membranes during treatment with 100 µmol/L of peptides. In the presence of 100 nmol/L [35S]GTPS, 5 µg of membranes was incubated for indicated periods with various synthetic peptides corresponding to the cytosolic regions of the AT1A receptor indicated in Fig 1. Values represent the mean of three independent experiments. B, Dose-response relationship for these synthetic peptides on the GTPS binding to G protein in COS-7 cell membranes. Membranes (5 µg) were incubated for 10 minutes with each peptide in the same setting as in A. The GTPS bound in 10 minutes, when binding was nearly complete as shown in A (100% is control GTPS bound in the absence of a peptide), is presented as a function of the concentrations of each peptide examined. Values represent the mean of three independent experiments.

Effect of Peptides on GTPS Binding to Purified G Proteins
Several species of G proteins exist in cellular membrane preparations. To determine individual species that interacted with each of the peptides, we examined the effect of all five synthetic peptides on [³⁵S]GTPS binding to purified G_i1, G_i2, and G_o proteins. As shown in Fig 3, peptides P-3 and P-5 activated purified G_i1, G_i2, and G_o. The peptides P-1, P-2, and P-4 showed no effect at 100 µmol/L. P-2 had an effect on [³⁵S]GTPS binding to G proteins in the membranes but not on purified G_i1, G_i2, and G_o. It is known that AT_1A couples with G_q protein,^{1 2} but we did not examine the effect of the peptides on GTPS binding to G_q because we did not have purified G_q. It is possible that P-2 may have an effect on the activation of G_q.

View larger version (12K): [in this window] [in a new window]   Figure 3. Bar graphs show the effect of synthetic peptides on GTPS binding to purified G proteins. Each purified G protein (10 nmol/L) was incubated with 100 nmol/L [35S]GTPS at room temperature in the absence (control) or presence of 100 µmol/L synthetic peptide (P-1 to P-5) for 10 minutes. A 50-µL aliquot of reaction mixture was subjected to the analysis of [35S]GTPS binding. Total GTPS binding to 0.5 pmol G protein was set as 100%. Data represent mean±SD of three independent experiments.

	Discussion

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In this article we describe the use of synthetic peptides derived from the rat AT_1A receptor to identify domains of the receptor involved in interactions with G protein. We investigated the several candidate domains of the receptor with two different approaches, one using COS-7 cell membranes and the other using purified G proteins. Peptides P-3 and P-5 produced consistent activation in both assays, strongly indicating a role of the third intracellular loop and C-terminal cytosolic domain in AT_1A receptors in G protein coupling. In contrast, none of the other AT_1A-derived peptides influenced GTPS binding. Our data are consistent with other studies which indicate that the third intracellular loop of a typical seven-transmembrane receptor, such as adrenergic and muscarinic receptors, is important for effective coupling to G protein. The proximal portion of the C-terminal tail of the receptor appears to be another determinant of AT_1A association with G protein, as evidenced by the effects produced by P-5 in the assays described. The activity of P-5 in these assays implies that the first one third of the cytoplasmic tail is important for effective AT_1A–G protein coupling. Again, it appears that this portion of the AT_1A receptor binds G proteins, as indicated by the ability of P-5 to activate GTPS binding to G_i1, G_i2, and G_o.

The coupling of G_o protein with AT_1A has not been clarified yet. AT_1A receptor and G_o protein are expressed abundantly in neuronal cells, and it has been reported that G_o inhibits neuronal calcium channels.⁷ Bacal and Kunze⁸ reported that Ang II inhibits -conotoxin GVIA (CTX)–sensitive calcium channels through a pertussis toxin–sensitive G protein coupled to AT₁ in rat nodose ganglion cells. This inhibitory effect was abolished by losartan, a specific antagonist, and preincubation with pertussis toxin. These data suggested that G_o protein coupled with AT_1A in neuronal cells. Mitchell et al³ reported the possibility of direct coupling of AT_1A and purified G_o protein in a reconstituted system. Our observation provides additional evidence for G_o protein coupling with AT_1A.

The present results suggest that G_i1, G_i2, and G_o proteins were activated by identical domains of AT_1A. However, the mechanism of regulation in the activation of each type of G protein is not clear. Ohnishi et al⁹ reported that Ang II at a low concentration (10^-11 mol/L) activated only G_i protein, but at a high concentration (10^-8 mol/L) it activated both G_q and G_i proteins. This observation strongly suggested that there are different activation mechanisms for G_q and G_i proteins. In the ß₂-adrenergic receptor, the C-terminal one third of the third cytoplasmic loop activates both G_s and G_i, and the activation is also regulated by phosphorylation by cAMP-dependent protein kinase A.²¹ This domain activates G_s when it is dephosphorylated, whereas when phosphorylated by protein kinase A, this domain activates G_i but not G_s. A similar regulatory mechanism may operate in AT_1A receptors.

We were not able to examine the effect of the peptides on GTPS binding to G_q protein because we did not have a purified G_q preparation. From our data of GTPS binding to G protein in COS-7 membranes, P-2, P-3, and P-5 activated GTPS binding, but P-2 did not activate purified G_i1, G_i2, or G_o protein. An identical experimental procedure has been used for binding studies with membranes and purified G proteins. Therefore, the positive effect of P-2 to the membrane preparation but not to purified G proteins may be explained by the possible action of P-2 on G_q in the membranes. Indeed, previous data from our laboratory collected with the use of mutated variants of AT_1A showed the importance of the second, third, and C-terminal cytosolic regions of AT_1A for G_q protein coupling.¹⁸ These results suggest a possible interaction of G_q with the second cytosolic domain, presumably P-2, of AT_1A.

The present data suggest that the third intracellular loop of AT_1A plays a critical role in the interaction of AT_1A with G protein in accord with similar observations made with many other G protein–coupled receptors. We also found that the first one third of the C-terminal tail of AT_1A is important for the interaction of AT_1A and G protein. A report from our laboratory provides an observation indicating that the C-terminal cytosolic tail of AT_1A is also a critical region for functional association with G protein.¹⁸ The synthetic peptide and mutagenesis studies strongly suggest that the third intracellular loop and C-terminal tail region of AT_1A play major roles in the physical and functional coupling of AT_1A to G proteins. In contrast, the adrenergic and muscarinic receptors, whose ligands are small nonpeptide molecules, require a part of the third intracellular loop for interaction with G protein.^{23 24 25 26 27} Cloning of receptors within the G protein–coupled superfamily has revealed that most of the receptors for peptidic ligands possess relatively short third intracellular loops²⁵ compared with the receptors for small ligands. For example, in neutrophil N-formyl peptide receptor, the C-terminal tail region was shown to have an important role for interaction with G protein as well as the second cytosolic loop.²⁸ It seems that many members of this receptor superfamily with short third cytosolic loops require more than one intracellular region for G protein binding. Not a single consensus structure has yet been identified within this receptor superfamily that uniquely defines the G protein binding structure. It may be that individual receptors may use different amino acid sequences in different domains of available intracellular regions. Several reports appeared on possible G protein coupling sites of AT_1A in which the site-directed mutagenesis method was used. Bihoreau et al²⁹ and Marie et al³⁰ made mutations in the transmembrane domains II and VII of AT_1A, respectively. These mutations resulted in a loss of G protein coupling presumably because of a conformational change that could cause conformational changes in domains other than the mutated amino acid residues. Hunyady et al³¹ made third cytoplasmic loop deletion mutants of AT_1A and reported that the N-terminal half of the third cytoplasmic loop (amino acid residues 215 through 226) was a critical region of G_q protein coupling. A series of mutational studies on basic polar amino acid residues in the second and third cytosolic loops of AT_1A by Ohyama et al¹⁸ suggested that the N-terminal half of the second cytoplasmic loop and C-terminal half of the third cytosolic loop would be important for G_q protein coupling. These conflicting results could be due to conformational changes that could be introduced by mutational substitutions of amino acid residues. It is interesting that no mutational change has been reported that causes activation of the G protein coupling with the AT_1A receptor. Because of the observation of positive activation, the synthetic peptide method for mapping of G protein coupling is useful. For the identification of the domain important for G_q protein coupling with AT_1A, purified G_q protein should turn out to be useful in a similar approach using synthetic peptides representing various cytosolic domains.

In summary, the present studies identified that the N-terminal half of the third cytoplasmic loop and C-terminal cytosolic tail of AT_1A receptors are important for G_i1, G_i2, and G_o protein coupling.

	Acknowledgments

 
This work was supported in part by research grants HL-14192 from the US Public Health Service and HL-35323 from the National Institutes of Health. We would like to thank Trinita Fitzgerald for her excellent technical assistance.

	References

Top Abstract Introduction Methods Results Discussion References

 
1. Inagami T, Iwai N, Sasaki K, Yamano Y, Bardhan S, Chaki S, Guo DF, Furuta H. Cloning, expression and regulation of angiotensin II receptors. J Hypertens. 1992;10:713-716. [Medline] [Order article via Infotrieve]

2. Crawford KW, Frey EA, Cote TE. Angiotensin II receptor recognized by Dup753 regulates two distinct guanine nucleotide-binding protein signaling pathways. Mol Pharmacol. 1992;41:154-162. [Abstract]

3. Mitchell J, Murphy EA, Northup JK. Reconstitution of agonist binding to uncoupled hepatic angiotensin II receptors with Gi and Go. The Endocrine Society Abstract. 1991;199.

4. Smrcka AV, Eerenz CR, Lellaher KL, Kriz RW, Knopf LJ. Regulation of polyphosphoinositide-specific phospholipase C activity by purified Gq. Science. 1991;251:804-807. [Abstract/Free Full Text]

5. Taylor SJ, Chae CZ, Rhee SG, Exton JH. Activation of the ß1 isozyme of phospholipase C by subunits of the Gq class of G proteins. Nature. 1991;350:516-518. [Medline] [Order article via Infotrieve]

6. Gilman AG. G proteins: transducers of receptor-generated signals. Annu Rev Biol. 1987;56:615-649.

7. Hescheler J, Rosenthal W, Trauwein W, Schultz G. The GTP-binding protein G_o regulates neuronal calcium channels. Nature. 1987;325:445-447. [Medline] [Order article via Infotrieve]

8. Bacal K, Kunze DL. Dual effects of angiotensin II on calcium currents in neonatal rat nodose neurons. J Neurosci. 1994;14:7159-7167. [Abstract]

9. Ohnishi J, Ishido M, Shibata T, Inagami T, Murakami K, Miyazaki H. The rat angiotensin II AT1a receptor couples with three different signal transduction pathways. Biochem Biophys Res Commun. 1992;186:1094-1101. [Medline] [Order article via Infotrieve]

10. May DC, Ross EM, Gilman AG, Smigel MD. Reconstitution of catecholamine-stimulated adenylate cyclase activity using three purified proteins. J Biol Chem. 1985;260:15829-15833. [Abstract/Free Full Text]

11. Feder D, Im MJ, Klein HW, Hekman M, Holzhofer A, Dees C, Levitzki A, Helmreich EJM, Pfeuffer T. Reconstitution of ß1-adrenoceptor-dependent adenylate cyclase from purified components. EMBO J. 1986;5:1509-1514. [Medline] [Order article via Infotrieve]

12. Sasaki K, Yamano Y, Bardhan S, Iwai N, Murray JJ, Hasegawa M, Matsuda Y, Inagami T. Cloning and expression of a complementary DNA encoding a bovine adrenal angiotensin II type-1 receptor. Nature. 1991;351:230-233. [Medline] [Order article via Infotrieve]

13. Murphy TJ, Alexander RW, Griedling KK, Runge MS, Bernstein KE. Isolation of a cDNA encoding the type-1 angiotensin II receptor. Nature. 1991;351:233-236. [Medline] [Order article via Infotrieve]

14. Takayanagi R, Ohnaka K, Sakai Y, Nakao R, Yanase T, Haji M, Inagami T, Furuta H, Guo DF, Nakamuta M, Nawata H. Molecular cloning, sequence analysis and expression of a cDNA encoding human type-1 angiotensin II receptor. Biochem Biophys Res Commun. 1992;183:910-917. [Medline] [Order article via Infotrieve]

15. Furuta H, Guo DF, Inagami T. Molecular cloning and sequencing of the gene encoding human angiotensin II type 1 receptor. Biochem Biophys Res Commun. 1992;183:8-13. [Medline] [Order article via Infotrieve]

16. Henderson R, Unwin PNT. Three-dimensional model of purple membrane obtained by electron microscopy. Nature. 1975;257:28-32. [Medline] [Order article via Infotrieve]

17. Ovchinnikov YA. Rhodopsin and bacteriorhodopsin: structure-function relationships. FEBS Lett. 1982;148:179-191. [Medline] [Order article via Infotrieve]

18. Ohyama K, Yamano Y, Chaki S, Kondo T, Inagami T. Domains for G-protein coupling in angiotensin II receptor type 1: studies by site-directed mutagenesis. Biochem Biophys Res Commun. 1992;189:1426-1431.

19. Kondo T, Konishi F, Inui H, Inagami T. Differing signal transductions elicited by isoforms of platelet-derived growth factor in vascular smooth muscle cells. J Biol Chem. 1993;268:4458-4464. [Abstract/Free Full Text]

20. Katada T, Oinuma M, Kusakabe K, Ui M. A new GTP-binding protein in brain tissue serving as the specific substrate of islet-activating protein, pertussis toxin. FEBS Lett. 1987;213:353-358. [Medline] [Order article via Infotrieve]

21. Okamoto T, Murayama Y, Hayashi Y, Inagaki M, Ogata E, Nishimoto I. Identification of a Gs activator region of the ß2-adrenergic receptor that is autoregulated via protein kinase A-dependent phosphorylation. Cell. 1991;67:723-730. [Medline] [Order article via Infotrieve]

22. Northup JK, Smigel MD, Gilman AG. The guanine nucleotide activating site of the regulatory component of adenylate cyclase. J Biol Chem. 1982;257:11416-11423. [Free Full Text]

23. Lefkowitz RJ, Caron MG. Adrenergic receptors, models for the study of receptors coupled to guanine nucleotide regulatory proteins. J Biol Chem. 1988;263:4993-4996. [Free Full Text]

24. Savarese TM, Fraser CM. In vitro mutagenesis and the search for structure-function relationships among G protein-coupled receptors. Biochem J. 1992;283:1-19.

25. Probst WC, Snyder LA, Schuster DI, Brosius J, Sealfon SC. Sequence alignment of the G-protein coupled receptor superfamily. DNA Cell Biol. 1992;2:1-20.

26. Strader CD, Sigal IS, Dixon RA. Structural basis of ß-adrenergic receptor function. FASEB J. 1989;3:1825-1832. [Abstract]

27. Strosberg AD. Structure/function relationship of proteins belonging to the family of receptors coupled to GTP-binding proteins. Eur J Biochem. 1991;196:1-10. [Medline] [Order article via Infotrieve]

28. Schreiber RE, Prossnitz ER, Ye RD, Cochrane CG, Bokoch GM. Domains of the human neutrophil N-formyl peptide receptor involved in G protein coupling. J Biol Chem. 1994;269:326-331. [Abstract/Free Full Text]

29. Bihoureau C, Monnot C, Davies E, Teutsch B, Bernstein KE, Corvol P, Clauser E. Mutation of Asp⁷⁴ of the rat angiotensin II receptor confers changes in antagonist affinities and abolishes G-protein coupling. Proc Natl Acad Sci U S A. 1993;90:5133-5137. [Abstract/Free Full Text]

30. Marie J, Maigret B, Joseph MP, Larguier R, Nouet S, Lombard C, Bonnafous JC. Tyr²⁹² in the seventh transmembrane domain of the AT_1A angiotensin II receptor is essential for its coupling to phospholipase C. J Biol Chem. 1994;269:20815-20818. [Abstract/Free Full Text]

31. Hunyady L, Baukal AJ, Balla T, Catt KJ. Independence of type 1 angiotensin II receptor endocytosis from G protein coupling and signal transduction. J Biol Chem. 1994;269:24798-24804.[Abstract/Free Full Text]

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				L. Saward Peter Zahradka Angiotensin II Activates Phosphatidylinositol 3-Kinase in Vascular Smooth Muscle Cells Circ. Res., August 19, 1997; 81(2): 249 - 257. [Abstract] [Full Text]

				B. C. Berk and M. A. Corson Angiotensin II Signal Transduction in Vascular Smooth Muscle : Role of Tyrosine Kinases Circ. Res., May 19, 1997; 80(5): 607 - 616. [Abstract] [Full Text]

				L. Franzoni, G. Nicastro, T. A. Pertinhez, M. Tato, C. R. Nakaie, A. C.M. Paiva, S. Schreier, and A. Spisni Structure of the C-terminal Fragment 300-320 of the Rat Angiotensin II AT1A Receptor and Its Relevance with Respect to G-Protein Coupling J. Biol. Chem., April 11, 1997; 272(15): 9734 - 9741. [Abstract] [Full Text] [PDF]

				N. Macrez-Lepretre, F. Kalkbrenner, J.-L. Morel, G. Schultz, and J. Mironneau G Protein Heterotrimer Galpha 13beta 1gamma 3 Couples the Angiotensin AT1A Receptor to Increases in Cytoplasmic Ca2+ in Rat Portal Vein Myocytes J. Biol. Chem., April 11, 1997; 272(15): 10095 - 10102. [Abstract] [Full Text] [PDF]

				D. D. D'Angelo, J. J. Eubank, M. G. Davis, and G. W. Dorn II Mutagenic Analysis of Platelet Thromboxane Receptor Cysteines J. Biol. Chem., March 15, 1996; 271(11): 6233 - 6240. [Abstract] [Full Text] [PDF]

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