seven-transmembrane G protein-coupled receptor superfamily; This hierarchical evolutionary model represents the seven-transmembrane (7TM) receptors, often referred to as G protein-coupled receptors (GPCRs), which transmit physiological signals from the outside of the cell to the inside via G proteins. GPCRs constitute the largest known superfamily of transmembrane receptors across the three kingdoms of life that respond to a wide variety of extracellular stimuli including peptides, lipids, neurotransmitters, amino acids, hormones, and sensory stimuli such as light, smell and taste. All GPCRs share a common structural architecture comprising of seven-transmembrane (TM) alpha-helices interconnected by three extracellular and three intracellular loops. A general feature of GPCR signaling is agonist-induced conformational changes in the receptors, leading to activation of the heterotrimeric G proteins, which consist of the guanine nucleotide-binding G-alpha subunit and the dimeric G-beta-gamma subunits. The activated G proteins then bind to and activate numerous downstream effector proteins, which generate second messengers that mediate a broad range of cellular and physiological processes. However, some 7TM receptors, such as the type 1 microbial rhodopsins, do not activate G proteins. Based on sequence similarity, GPCRs can be divided into six major classes: class A (the rhodopsin-like family), class B (the Methuselah-like, adhesion and secretin-like receptor family), class C (the metabotropic glutamate receptor family), class D (the fungal mating pheromone receptors), class E (the cAMP receptor family), and class F (the frizzled/smoothened receptor family). Nearly 800 human GPCR genes have been identified and are involved essentially in all major physiological processes. Approximately 40% of clinically marketed drugs mediate their effects through modulation of GPCR function for the treatment of a variety of human diseases including bacterial infections.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435   1 RVVRYLQVVVLlYASTYVLVSLSIDRYHAIVYPM------------IVIAWSLSFLFSIPTLIIFGKRTLSNGEVQCWAL 68
Cdd:cd15197  74 KVIRYLQVVVT-YASTYVLVALSIDRYDAICHPMnfsqsgrqarvlICVAWILSALFSIPMLIIFEKTGLSNGEVQCWIL 152

                        90       100       110       120       130       140       150       160
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435  69 WPDDSYWTPYMTIVAFLVYFIP---------------------------------------------------------- 90
Cdd:cd15197 153 WPEPWYWKVYMTIVAFLVFFIPatiisicyiiivrtiwkkskiqvtinkaglhdgssrrsssrgiiprakiktikmtfvi 232

                       170       180       190       200
                ....*....|....*....|....*....|....*....|..
gi 29611435  91 ---FICCWSPYFLFDILDNFNLLPDTQERFYASVIIQNLPAL 129
Cdd:cd15197 233 vtvFIICWSPYFVFDLLDVFGLLPRSKTKIAAATFIQSLAPL 274

neuropeptide S receptor, member of the class A family of seven-transmembrane G protein-coupled receptors; Neuropeptide S (NPS) promotes arousal and anxiolytic-like effects by activating its cognate receptor NPSR. NPSR is widely expressed in the brain, and its activation induces an elevation of intracellular calcium and cAMP concentrations, presumably by coupling to G(s) and G(q) proteins. Mutations in NPSR have been associated with an increased susceptibility to asthma. NPSR was originally identified as an orphan receptor GPR154 and is also known as G protein receptor for asthma susceptibility (GPRA) or vasopressin receptor-related receptor 1 (VRR1).

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435   1 RVVRYLQVVVLlYASTYVLVSLSIDRYHAIVYPM------------IVIAWSLSFLFSIPTLIIFGKRTLSNGEVQCWAL 68
Cdd:cd15197  74 KVIRYLQVVVT-YASTYVLVALSIDRYDAICHPMnfsqsgrqarvlICVAWILSALFSIPMLIIFEKTGLSNGEVQCWIL 152

                        90       100       110       120       130       140       150       160
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435  69 WPDDSYWTPYMTIVAFLVYFIP---------------------------------------------------------- 90
Cdd:cd15197 153 WPEPWYWKVYMTIVAFLVFFIPatiisicyiiivrtiwkkskiqvtinkaglhdgssrrsssrgiiprakiktikmtfvi 232

                       170       180       190       200
                ....*....|....*....|....*....|....*....|..
gi 29611435  91 ---FICCWSPYFLFDILDNFNLLPDTQERFYASVIIQNLPAL 129
Cdd:cd15197 233 vtvFIICWSPYFVFDLLDVFGLLPRSKTKIAAATFIQSLAPL 274

neuropeptide S receptor, member of the class A family of seven-transmembrane G protein-coupled receptors; Neuropeptide S (NPS) promotes arousal and anxiolytic-like effects by activating its cognate receptor NPSR. NPSR is widely expressed in the brain, and its activation induces an elevation of intracellular calcium and cAMP concentrations, presumably by coupling to G(s) and G(q) proteins. Mutations in NPSR have been associated with an increased susceptibility to asthma. NPSR was originally identified as an orphan receptor GPR154 and is also known as G protein receptor for asthma susceptibility (GPRA) or vasopressin receptor-related receptor 1 (VRR1).

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435   1 RVVRYLQVVVLlYASTYVLVSLSIDRYHAIVYPM------------IVIAWSLSFLFSIPTLIIFGKRTLSNGEVQCWAL 68
Cdd:cd15197  74 KVIRYLQVVVT-YASTYVLVALSIDRYDAICHPMnfsqsgrqarvlICVAWILSALFSIPMLIIFEKTGLSNGEVQCWIL 152

                        90       100       110       120       130       140       150       160
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435  69 WPDDSYWTPYMTIVAFLVYFIP---------------------------------------------------------- 90
Cdd:cd15197 153 WPEPWYWKVYMTIVAFLVFFIPatiisicyiiivrtiwkkskiqvtinkaglhdgssrrsssrgiiprakiktikmtfvi 232

                       170       180       190       200
                ....*....|....*....|....*....|....*....|..
gi 29611435  91 ---FICCWSPYFLFDILDNFNLLPDTQERFYASVIIQNLPAL 129
Cdd:cd15197 233 vtvFIICWSPYFVFDLLDVFGLLPRSKTKIAAATFIQSLAPL 274

vasopressin and oxytocin receptors, member of the class A family of seven-transmembrane G protein-coupled receptors; Vasopressin (also known as arginine vasopressin or anti-diuretic hormone) and oxytocin are synthesized in the hypothalamus and are released from the posterior pituitary gland. The actions of vasopressin are mediated by the interaction of this hormone with three receptor subtypes: V1aR, V1bR, and V2R. These subtypes are differ in localization, function, and signaling pathways. Activation of V1aR and V1bR stimulate phospholipase C, while activation of V2R stimulates adenylate cyclase. Although vasopressin and oxytocin differ only by two amino acids and stimulate the same cAMP/PKA pathway, they have divergent physiological functions. Vasopressin is involved in regulating blood pressure and the balance of water and sodium ions, whereas oxytocin plays an important role in the uterus during childbirth and in lactation.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435   1 RVVRYLQVVVLlYASTYVLVSLSIDRYHAIVYP-------------MIVIAWSLSFLFSIPTLIIFGKRTLSNGEVQCWA 67
Cdd:cd15196  74 RLVKYLQVVGM-YASSYVLVATAIDRYIAICHPlsshrwtsrrvhlMVAIAWVLSLLLSIPQLFIFSYQEVGSGVYDCWA 152

                        90       100
                ....*....|....*....|....*.
gi 29611435  68 LWPDDSYWTPYMTIVAFLVYFIPFIC 93
Cdd:cd15196 153 TFEPPWGLRAYITWFTVAVFVVPLII 178

oxytocin receptor, member of the class A family of seven-transmembrane G protein-coupled receptors; Oxytocin is a peptide of nine amino acids synthesized in the hypothalamus and is released from the posterior pituitary gland. Oxytocin plays an important role in sexual reproduction of both sexes and is structurally very similar to vasopressin. Although vasopressin and oxytocin differ only by two amino acids and stimulate the same cAMP/PKA pathway, they have divergent physiological functions. Vasopressin is involved in regulating blood pressure and the balance of water and sodium ions, whereas oxytocin plays an important role in the uterus during childbirth and in lactation.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435   1 RVVRYLQVVVLlYASTYVLVSLSIDRYHAIVYPM-----------IVIAWSLSFLFSIPTLIIFGKRTLSNGEVQCWALW 69
Cdd:cd15387  74 RLVKYLQVVGM-FASTYMLLLMSIDRCLAICQPLrslhrrsdrvyVLFSWLLSLVFSIPQVHIFSLREVGNGVYDCWADF 152

                        90       100       110       120
                ....*....|....*....|....*....|....*....|..
gi 29611435  70 PDDSYWTPYMTIVAFLVYFIPFICCWSPYFL--FDILDNFNL 109
Cdd:cd15387 153 IQPWGPKAYITWITLSVYIIPVLILSVCYGLisFKIWQNVKL 194

gonadotropin-releasing hormone and adipokinetic hormone receptors, member of the class A family of seven-transmembrane G protein-coupled receptors; Gonadotropin-releasing hormone (GnRH) and adipokinetic hormone (AKH) receptors share strong sequence homology to each other, suggesting that they have a common evolutionary origin. GnRHR, also known as luteinizing hormone releasing hormone receptor (LHRHR), plays an central role in vertebrate reproductive function; its activation by binding to GnRH leads to the release of follicle stimulating hormone (FSH) and luteinizing hormone (LH) from the pituitary gland. Adipokinetic hormone (AKH) is a lipid-mobilizing hormone that is involved in control of insect metabolism. Generally, AKH behaves as a typical stress hormone by mobilizing lipids, carbohydrates and/or certain amino acids such as proline. Thus, it utilizes the body's energy reserves to fight the immediate stress problems and subdue processes that are less important. Although AKH is known to responsible for regulating the energy metabolism during insect flying, it is also found in insects that have lost its functional wings and predominantly walk for their locomotion. Both GnRH and AKH receptors are members of the class A of the seven-transmembrane, G-protein coupled receptor (GPCR) superfamily.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435  12 LYASTYVLVSLSIDRYHAIVYP------------MIVIAWSLSFLFSIPTLIIFG---KRTLSNGEVQC--WALWPDDSY 74
Cdd:cd15195  84 MYLSSFMLVVIALDRVFAILSPlsanqarkrvkiMLTVAWVLSALCSIPQSFIFSvlrKMPEQPGFHQCvdFGSAPTKKQ 163

                        90       100
                ....*....|....*....|....*.
gi 29611435  75 WTPYMTIVAFLVYFIPFICCWSPYFL 100
Cdd:cd15195 164 ERLYYFFTMILSFVIPLIITVTCYLL 189

vertebrate gonadotropin-releasing hormone receptors, member of the class A family of seven-transmembrane G protein-coupled receptors; GnRHR, also known as luteinizing hormone releasing hormone receptor (LHRHR), plays an central role in vertebrate reproductive function; its activation by binding to GnRH leads to the release of follicle stimulating hormone (FSH) and luteinizing hormone (LH) from the pituitary gland. GnRHR is expressed predominantly in the gonadotrope membrane of the anterior pituitary as well as found in numerous extrapituitary tissues including lymphocytes, breast, ovary, prostate, and cancer cell lines. There are at least two types of GnRH receptors, GnRHR1 and GnRHR2, which couple primarily to G proteins of the Gq/11 family. GnRHR is closely related to the adipokinetic hormone receptor (AKH), which binds to a lipid-mobilizing hormone that is involved in control of insect metabolism. They share a common ancestor and are members of the class A of the seven-transmembrane, G-protein coupled receptor (GPCR) superfamily.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435   1 RVVRYLQVVVLlYASTYVLVSLSIDRYHAIVYP------------MIVIAWSLSFLFSIPTLIIFGKRTLSNGE--VQCW 66
Cdd:cd15383  75 RLLMFLKLFAM-YSSAFVTVVISLDRHAAILNPlaigsarrrnriMLCAAWGLSALLALPQLFLFHTVTATPPVnfTQCA 153

                        90       100       110
                ....*....|....*....|....*....|....*
gi 29611435  67 ALWPDDSYW--TPYMTIVAFLVYFIPF---ICCWS 96
Cdd:cd15383 154 THGSFPAHWqeTLYNMFTFFCLFLLPLlimIFCYT 188

rhodopsin receptor-like class A family of the seven-transmembrane G protein-coupled receptor superfamily; Class A rhodopsin-like receptors constitute about 90% of all GPCRs. The class A GPCRs include the light-sensitive rhodopsin as well as receptors for biogenic amines, lipids, nucleotides, odorants, peptide hormones, and a variety of other ligands. All GPCRs have a common structural architecture comprising of seven-transmembrane (TM) alpha-helices interconnected by three extracellular and three intracellular loops. A general feature of GPCR signaling is agonist-induced conformational changes in the receptors, leading to activation of the heterotrimeric G proteins, which consist of the guanine nucleotide-binding G-alpha subunit and the dimeric G-beta-gamma subunits. The activated G proteins then bind to and activate numerous downstream effector proteins, which generate second messengers that mediate a broad range of cellular and physiological processes. Based on sequence similarity, GPCRs can be divided into six major classes: class A (rhodopsin-like family), class B (Methuselah-like, adhesion and secretin-like receptor family), class C (metabotropic glutamate receptor family), class D (fungal mating pheromone receptors), class E (cAMP receptor family), and class F (frizzled/smoothened receptor family). Nearly 800 human GPCR genes have been identified and are involved essentially in all major physiological processes. Approximately 40% of clinically marketed drugs mediate their effects through modulation of GPCR function for the treatment of a variety of human diseases including bacterial infections.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435   8 VVVLLYASTYVLVSLSIDRYHAIVYP--------------MIVIAWSLSFLFSIPTLIIFGKRTLsNGEVQCWALWPDDS 73
Cdd:cd00637  78 QSVSLLASILTLTAISVDRYLAIVHPlryrrrftrrraklLIALIWLLSLLLALPPLLGWGVYDY-GGYCCCCLCWPDLT 156

                        90       100
                ....*....|....*....|
gi 29611435  74 YWTPYMTIVAFLVYFIPFIC 93
Cdd:cd00637 157 LSKAYTIFLFVLLFLLPLLV 176

neuropeptide Y receptor-like found in insect and related proteins, member of the class A family of seven-transmembrane G protein-coupled receptors; This subgroup includes a novel G protein-coupled receptor (also known as PR4 receptor) from Drosophila melanogaster, which can be activated by the members of the neuropeptide Y (NPY) family, including NPY, peptide YY (PYY) and pancreatic polypeptide (PP), when expressed in Xenopus oocytes. These homologous peptides of 36-amino acids in length contain a hairpin-like structural motif, which referred to as the pancreatic polypeptide fold, and function as gastrointestinal hormones and neurotransmitters. The PR4 receptor also shares strong sequence homology to the mammalian tachykinin receptors (NK1R, NK2R, and NK3R), whose endogenous ligands are substance P (SP), neurokinin A (NKA), and neurokinin B (NKB), respectively. The tachykinins function as excitatory transmitters on neurons and cells in the gastrointestinal tract.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435   2 VVRYLQVVVLLyASTYVLVSLSIDRYHAIVYPM----------IVIA--WSLSFLFSIPTLI---IFGKRTLSNGEVQCW 66
Cdd:cd15392  76 VVNYLQAVSVF-VSAFTLVAISIDRYVAIMWPLrprmtkrqalLLIAviWIFALATALPIAItsrLFEDSNASCGQYICT 154

                        90       100
                ....*....|....*....|....
gi 29611435  67 ALWPDDSYWTPYMTIVAFLVYFIP 90
Cdd:cd15392 155 ESWPSDTNRYIYSLVLMILQYFVP 178

invertebrate gonadotropin-releasing hormone receptors, member of the class A family of seven-transmembrane G protein-coupled receptors; GnRHR, also known as luteinizing hormone releasing hormone receptor (LHRHR), plays an central role in vertebrate reproductive function; its activation by binding to GnRH leads to the release of follicle stimulating hormone (FSH) and luteinizing hormone (LH) from the pituitary gland. GnRHR is expressed predominantly in the gonadotrope membrane of the anterior pituitary as well as found in numerous extrapituitary tissues including lymphocytes, breast, ovary, prostate, and cancer cell lines. There are at least two types of GnRH receptors, GnRHR1 and GnRHR2, which couple primarily to G proteins of the Gq/11 family. GnRHR is closely related to the adipokinetic hormone receptor (AKH), which binds to a lipid-mobilizing hormone that is involved in control of insect metabolism. They share a common ancestor and are members of the class A of the seven-transmembrane, G-protein coupled receptor (GPCR) superfamily.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 29611435   1 RVVRYLQVVVLlYASTYVLVSLSIDRYHAIVYPM------------IVIAWSLSFLFSIPTLIIF 53
Cdd:cd15384  74 KLVKYLQVFGL-YLSTYITVLISLDRCVAILYPMkrnqapervrrmVTVAWILSPIFSIPQAVIF 137

KiSS1-derived peptide (kisspeptin) receptor, member of the class A family of seven-transmembrane G protein-coupled receptors; The G protein-coupled KiSS1-derived peptide receptor (GPR54 or kisspeptin receptor) binds the peptide hormone kisspeptin (previously known as metastin), which encoded by the metastasis suppressor gene (KISS1) expressed in various endocrine and reproductive tissues. The KiSS1 receptor is coupled to G proteins of the G(q/11) family, which lead to activation of phospholipase C and increase of intracellular calcium. This signaling cascade plays an important role in reproduction by regulating the secretion of gonadotropin-releasing hormone.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435   1 RVVRYLQVVVLlYASTYVLVSLSIDRYHAIVYP------------MIVIA--WSLSFLFSIPTLIIFGKRTLSNGEVQ-- 64
Cdd:cd15095  74 KFVNYMMQVTV-QATCLTLTALSVDRYYAIVHPirslrfrtprvaVVVSAciWIVSFLLSIPVAIYYRLEEGYWYGPQty 152

                        90       100       110
                ....*....|....*....|....*....|
gi 29611435  65 CWALWPDDSYWTPYMTIVAFLVYFIPFICC 94
Cdd:cd15095 153 CREVWPSKAFQKAYMIYTVLLTYVIPLAII 182

neurokinin receptors (or tachykinin receptors), member of the class A family of seven-transmembrane G protein-coupled receptors; This group represents G-protein coupled receptors for a variety of neuropeptides of the tachykinin (TK) family. The tachykinins are widely distributed throughout the mammalian central and peripheral nervous systems and act as excitatory transmitters on neurons and cells in the gastrointestinal tract. The TKs are characterized by a common five-amino acid C-terminal sequence, Phe-X-Gly-Leu-Met-NH2, where X is a hydrophobic residue. The three major mammalian tachykinins are substance P (SP), neurokinin A (NKA), and neurokinin B (NKB). The physiological actions of tachykinins are mediated through three types of receptors: neurokinin receptor type 1 (NK1R), NK2R, and NK3R. SP is a high-affinity endogenous ligand for NK1R, which interacts with the Gq protein and activates phospholipase C, leading to elevation of intracellular calcium. NK2R is a high-affinity receptor for NKA, the tachykinin neuropeptide substance K. SP and NKA are found in the enteric nervous system and mediate in the regulation of gastrointestinal motility, secretion, vascular permeability, and pain perception. NK3R is activated by its high-affinity ligand, NKB, which is primarily involved in the central nervous system and plays a critical role in the regulation of gonadotropin hormone release and the onset of puberty.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435  14 ASTYVLVSLSIDRYHAIVYPM------------IVIAWSLSFLFSIPTLIIFG----KRTLSNGEVQCWALWPDDSYWTP 77
Cdd:cd15390  86 ASVFTLMAISIDRYIAIVHPLrprlsrrttkiaIAVIWLASFLLALPQLLYSTtetyYYYTGSERTVCFIAWPDGPNSLQ 165

                        90
                ....*....|....*...
gi 29611435  78 ---YMTIVAFLVYFIPFI 92
Cdd:cd15390 166 dfvYNIVLFVVTYFLPLI 183

galanin receptor and related proteins, member of the class A family of seven-transmembrane G protein-coupled receptors; This subfamily includes G-protein coupled galanin receptors, kisspeptin receptor and allatostatin-A receptor (AstA-R) in insects. These receptors, which are members of the class A of seven transmembrane GPCRs, share a high degree of sequence homology among themselves. The galanin receptors bind galanin, a neuropeptide that is widely expressed in the brain, peripheral tissues, and endocrine glands. Galanin is implicated in numerous neurological and psychiatric diseases including Alzheimer's disease, eating disorders, and epilepsy, among many others. KiSS1-derived peptide receptor (also known as GPR54 or kisspeptin receptor) binds the peptide hormone kisspeptin (metastin), which encoded by the metastasis suppressor gene (KISS1) expressed in various endocrine and reproductive tissues. AstA-R is a G-protein coupled receptor that binds allatostatin A. Three distinct types of allatostatin have been identified in the insects and crustaceans: AstA, AstB, and AstC. They both inhibit the biosynthesis of juvenile hormone and exert an inhibitory influence on food intake. Therefore, allatostatins are considered as potential targets for insect control.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435   1 RVVRYLQVVVLLyASTYVLVSLSIDRYHAIVYPM--------------IVIAWSLSFLFSIPTLIIFGKRTLSNGEVQ-C 65
Cdd:cd14971  74 KFVHYFQQVSMH-ASIFTLVAMSLDRFLAVVYPLrslhirtprnalaaSGCIWVVSLAVAAPVLALHRLRNYTPGNRTvC 152

                        90       100       110
                ....*....|....*....|....*....|...
gi 29611435  66 WALWPDDSYWTPYMTIVAFLVYFIPFICCWSPY 98
Cdd:cd14971 153 SEAWPSRAHRRAFALCTFLFGYLLPLLLICVCY 185

orexin receptors, member of the class A family of seven-transmembrane G protein-coupled receptors; Orexins (OXs, also referred to as hypocretins) are neuropeptide hormones that regulate the sleep-wake cycle and potently influence homeostatic systems regulating appetite and feeding behavior or modulating emotional responses such as anxiety or panic. OXs are synthesized as prepro-orexin (PPO) in the hypothalamus and then proteolytically cleaved into two forms of isoforms: orexin-A (OX-A) and orexin-B (OX-B). OXA is a 33 amino-acid peptide with N-terminal pyroglutamyl residue and two intramolecular disulfide bonds, whereas OXB is a 28 amino-acid linear peptide with no disulfide bonds. OX-A binds orexin receptor 1 (OX1R) with high-affinity, but also binds with somewhat low-affinity to OX2R, and signals primarily to Gq coupling, whereas OX-B shows a strong preference for the orexin receptor 2 (OX2R) and signals through Gq or Gi/o coupling. Thus, activation of OX1R or OX2R will activate phospholipase activity and the phosphatidylinositol and calcium signaling pathways. Additionally, OX2R activation can also lead to inhibition of adenylate cyclase.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435   1 RVVRYLQVVVLLyASTYVLVSLSIDRYHAIVYP------------MIVIAWSLSFLFSIPTLII------FGKRTLSNGE 62
Cdd:cd15208  74 KIIPYLQTVSVS-VSVLTLSCIALDRWYAICHPlmfkstakrarvSILIIWIVSLLIMIPQAIVmecsrvVPLANKTILL 152

                        90       100
                ....*....|....*....|....*....
gi 29611435  63 VQCWALWPDDSYWTPYMTIVAFLVYFIPF 91
Cdd:cd15208 153 TVCDERWSDSIYQKVYHICFFLVTYLLPL 181

purinoceptor and its related proteins, member of the class A family of seven-transmembrane G protein-coupled receptors; Members of this subfamily include lysophosphatidic acid receptor, P2 purinoceptor, protease-activated receptor, platelet-activating factor receptor, Epstein-Barr virus induced gene 2, proton-sensing G protein-coupled receptors, GPR35, and GPR55, among others. All GPCRs have a common structural architecture comprising of seven-transmembrane (TM) alpha-helices interconnected by three extracellular and three intracellular loops. A general feature of GPCR signaling is agonist-induced conformational changes in the receptors, leading to activation of the heterotrimeric G proteins, which consist of the guanine nucleotide-binding G-alpha subunit and the dimeric G-beta-gamma subunits. The activated G proteins then bind to and activate numerous downstream effector proteins, which generate second messengers that mediate a broad range of cellular and physiological processes.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435  12 LYASTYVLVSLSIDRYHAIVYP-------------MIVIA-WSLSFLFSIPTLIIFGKRTLSNGEVQCWALWPDDSYWTP 77
Cdd:cd14982  84 MYGSILFLTCISVDRYLAVVHPlksrrlrrkryavGVCAGvWILVLVASVPLLLLRSTIAKENNSTTCFEFLSEWLASAA 163

                        90
                ....*....|....*.
gi 29611435  78 YMTIVAFLV-YFIPFI 92
Cdd:cd14982 164 PIVLIALVVgFLIPLL 179

cholecystokinin receptors, member of the class A family of seven-transmembrane G protein-coupled receptors; Cholecystokinin receptors (CCK-AR and CCK-BR) are a group of G-protein coupled receptors which bind the peptide hormones cholecystokinin (CCK) or gastrin. CCK, which facilitates digestion in the small intestine, and gastrin, a major regulator of gastric acid secretion, are highly similar peptides. Like gastrin, CCK is a naturally-occurring linear peptide that is synthesized as a preprohormone, then proteolytically cleaved to form a family of peptides with the common C-terminal sequence (Gly-Trp-Met-Asp-Phe-NH2), which is required for full biological activity. CCK-AR (type A, alimentary; also known as CCK1R) is found abundantly on pancreatic acinar cells and binds only sulfated CCK-peptides with very high affinity, whereas CCK-BR (type B, brain; also known as CCK2R), the predominant form in the brain and stomach, binds CCK or gastrin and discriminates poorly between sulfated and non-sulfated peptides. CCK is implicated in regulation of digestion, appetite control, and body weight, and is involved in neurogenesis via CCK-AR. There is some evidence to support that CCK and gastrin, via their receptors, are involved in promoting cancer development and progression, acting as growth and invasion factors.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435   1 RVVRYLQVVVLlYASTYVLVSLSIDRYHAIVYP--------------MIVIAWSLSFLFSIPTLIIFGKRTLSN-GEVQC 65
Cdd:cd15206  74 KLIPYFQAVSV-SVSTFTLVAISLERYFAICHPlksrvwqtlshaykVIAGIWLLSFLIMSPILVFSNLIPMSRpGGHKC 152

                        90       100
                ....*....|....*....|....*..
gi 29611435  66 WALWPDDSYWTPYMTIVAFLVYFIPFI 92
Cdd:cd15206 153 REVWPNEIAEQAWYVFLDLMLLVIPGL 179

melanin concentrating hormone receptor, member of the class A family of seven-transmembrane G protein-coupled receptors; Melanin-concentrating hormone receptor (MCHR) binds melanin concentrating hormone and is presumably involved in the neuronal regulation of food intake and energy homeostasis. Despite strong homology with somatostatin receptors, MCHR does not appear to bind somatostatin. Two MCHRs have been characterized in vertebrates, MCHR1 and MCHR2. MCHR1 is expressed in all mammals, whereas MCHR2 is only expressed in the higher order mammals, such as humans, primates, and dogs, and is not found in rodents. All GPCRs have a common structural architecture comprising of seven-transmembrane (TM) alpha-helices interconnected by three extracellular and three intracellular loops. A general feature of GPCR signaling is agonist-induced conformational changes in the receptors, leading to activation of the heterotrimeric G proteins, which consist of the guanine nucleotide-binding G-alpha subunit and the dimeric G-beta-gamma subunits. The activated G proteins then bind to and activate numerous downstream effector proteins, which generate second messengers that mediate a broad range of cellular and physiological processes.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435  13 YASTYVLVSLSIDRYHAIVYPM--------------IVIAWSLSFLFSIPTLIIFGKRTLSNGEVQCWALWP--DDSYW- 75
Cdd:cd15088  85 FTSTYILTAMSVDRYLAVVHPIrstkyrtrfvaklvNVGLWAASFLSILPVWVYSSLIYFPDGTTFCYVSLPspDDLYWf 164

                        90       100
                ....*....|....*....|
gi 29611435  76 TPYMTIVAFLVYFIPFICCW 95
Cdd:cd15088 165 TIYHFILGFAVPLVVITVCY 184

leucokinin-like peptide receptor from tick and related proteins, member of the class A family of seven-transmembrane G protein-coupled receptors; This subgroup includes a leucokinin-like peptide receptor from the Southern cattle tick, Boophilus microplus, a pest of cattle world-wide. Leucokinins are invertebrate neuropeptides that exhibit myotropic and diuretic activity. This receptor is the first neuropeptide receptor known from the Acari and the second known in the subfamily of leucokinin-like peptide G-protein-coupled receptors. The other known leucokinin-like peptide receptor is a lymnokinin receptor from the mollusc Lymnaea stagnalis.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435   1 RVVRYLQVVVLLyASTYVLVSLSIDRYHAIVYPM------------IVIAWSLSFLFSIPTLIIFGKRTL----SNGEVQ 64
Cdd:cd15393  74 PFCPFVQVLSVN-VSVFTLTVIAVDRYRAVIHPLkarcskksakiiILIIWILALLVALPVALALRVEELtdktNNGVKP 152

                        90       100
                ....*....|....*....|....*....
gi 29611435  65 -CWALWPDDSYWTPYMTIVAFLVYFIPFI 92
Cdd:cd15393 153 fCLPVGPSDDWWKIYNLYLVCVQYFVPLV 181

somatostatin receptor type 4, member of the class A family of seven-transmembrane G protein-coupled receptors; G protein-coupled somatostatin receptors (SSTRs) are composed of five distinct subtypes (SSTR1-5) that display strong sequence similarity with opioid receptors. All five receptor subtypes bind the natural somatostatin (somatotropin release inhibiting factor), a polypeptide hormone that regulates a wide variety of physiological functions such as neurotransmission, cell proliferation, contractility of smooth muscle cells, and endocrine signaling as well as inhibition of the release of many secondary hormones. SSTR4 plays a critical role in mediating inflammation. Unlike other SSTRs, SSTR4 subtype is not detected in all pituitary adenomas while it is expressed in the normal human pituitary.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435  12 LYASTYVLVSLSIDRYHAIVYP-------------MIVIA-WSLSFLFSIPTLIIFGKRTLSNGEVQCWALWPDDSYWTP 77
Cdd:cd15973  83 MFTSVFCLTVLSVDRYIAVVHPlraaryrrptvakMINICvWILSLLVISPIIIFADTATRKGQAVACNLIWPHPAWSAA 162

                        90       100
                ....*....|....*....|...
gi 29611435  78 YMTIVAFLVYFIPFICCWSPYFL 100
Cdd:cd15973 163 FVIYTFLLGFLLPVLAIGLCYIL 185

melanin concentrating hormone receptor 1, member of the class A family of seven-transmembrane G protein-coupled receptors; Melanin-concentrating hormone receptor (MCHR) binds melanin concentrating hormone and is presumably involved in the neuronal regulation of food intake and energy homeostasis. Despite strong homology with somatostatin receptors, MCHR does not appear to bind somatostatin. Two MCHRs have been characterized in vertebrates, MCHR1 and MCHR2. MCHR1 is expressed in all mammals, whereas MCHR2 is only expressed in the higher order mammals, such as humans, primates, and dogs, and is not found in rodents. All GPCRs have a common structural architecture comprising of seven-transmembrane (TM) alpha-helices interconnected by three extracellular and three intracellular loops. A general feature of GPCR signaling is agonist-induced conformational changes in the receptors, leading to activation of the heterotrimeric G proteins, which consist of the guanine nucleotide-binding G-alpha subunit and the dimeric G-beta-gamma subunits. The activated G proteins then bind to and activate numerous downstream effector proteins, which generate second messengers that mediate a broad range of cellular and physiological processes.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435  13 YASTYVLVSLSIDRYHAIVYPM--------------IVIAWSLSFLFSIPTLIIFGKRTLSNGEVQCWALWPD---DSYW 75
Cdd:cd15338  88 ITSTYILTVMTLDRYLATVHPIrstkirtprvavavICLVWILSLLSITPVWMYAGLMPLPDGSVGCALLLPNpetDTYW 167

                        90       100
                ....*....|....*....|....
gi 29611435  76 tpYMTIVAFLVYFIPFICCWSPYF 99
Cdd:cd15338 168 --FTLYQFFLAFALPLVVICVVYF 189

G protein-coupled receptor 150, member of the class A family of seven-transmembrane G protein-coupled receptors; GPR150 is an orphan receptor closely related to the oxytocin and vasopressin receptors. Its endogenous ligand is not known. These receptors share a significant amino acid sequence similarity, suggesting that they have a common evolutionary origin.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435   1 RVVRYLQVVVLLyASTYVLVSLSIDRYHAIVYP---------MIVIAWSLSFLFSIPTLIIFGKRTLSN------GEVQC 65
Cdd:cd15198  75 RLLKLLQASARG-ASANLVVLLALDRHQAIRAPlgqplrawkLAALGWLLALLLALPQAYVFRVDFPDDpasawpGHTLC 153

                        90       100
                ....*....|....*....|....*...
gi 29611435  66 WALWPDDSYW--TPYMTIVAFLVYFIPF 91
Cdd:cd15198 154 RGIFAPLPRWhlQVYATYEAVVGFVAPV 181

neurotensin receptors and related G protein-coupled receptors, member of the class A family of seven-transmembrane G protein-coupled receptors; This subfamily includes the neurotensin receptors and related G-protein coupled receptors, including neuromedin U receptors, growth hormone secretagogue receptor, motilin receptor, the putative GPR39 and the capa receptors from insects. These receptors all bind peptide hormones with diverse physiological effects. All GPCRs have a common structural architecture comprising of seven-transmembrane (TM) alpha-helices interconnected by three extracellular and three intracellular loops. A general feature of GPCR signaling is agonist-induced conformational changes in the receptors, leading to activation of the heterotrimeric G proteins, which consist of the guanine nucleotide-binding G-alpha subunit and the dimeric G-beta-gamma subunits. The activated G proteins then bind to and activate numerous downstream effector proteins, which generate second messengers that mediate a broad range of cellular and physiological processes.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435  13 YASTYVLVSLSIDRYHAIVYPM--------------IVIAWSLSFLFSIPTLIIFGKRTLS---NGEVQCWA---LWPDD 72
Cdd:cd14979  86 YATVLTIVALSVERYVAICHPLkaktlvtkrrvkrfILAIWLVSILCAIPILFLMGIQYLNgplPGPVPDSAvctLVVDR 165

                        90       100
                ....*....|....*....|....*...
gi 29611435  73 SYWTPYMTIVAFLVYFIPFICCWSPYFL 100
Cdd:cd14979 166 STFKYVFQVSTFIFFVLPMFVISILYFR 193

type 1 angiotensin II receptor, member of the class A family of seven-transmembrane G protein-coupled receptors; Angiotensin II (Ang II), the main effector in the renin-angiotensin system, plays a crucial role in the regulation of cardiovascular homeostasis through its type 1 (AT1) and type 2 (AT2) receptors. Ang II contributes to cardiovascular diseases such as hypertension and atherosclerosis via AT1R activation. Ang II increases blood pressure through Gq-mediated activation of phospholipase C, resulting in phosphoinositide (PI) hydrolysis and increased intracellular calcium levels. Through the AT2R, Ang II counteracts the vasoconstrictor action of AT1R and thereby induces vasodilation, sodium excretion, and reduction of blood pressure. Moreover, AT1R promotes cell proliferation, whereas AT2R inhibits proliferation and stimulates cell differentiation. The AT2R is highly expressed during fetal development, however it is scarcely present in adult tissues and is induced in pathological conditions. Generally, the AT1R mediates many actions of Ang II, while the AT2R is involved in the regulation of blood pressure and renal function.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435  12 LYASTYVLVSLSIDRYHAIVYPM--------------IVIAWSLSFLFSIPTLIIFGKRTLSNGEVQCWALWPDD--SYW 75
Cdd:cd15192  84 LYASVFLLTCLSIDRYLAIVHPMksrlrrtlvvarvtCIVIWLLAGVASLPAIIHRDVFFIENTNITVCAFHYPSqnSTL 163

                        90       100
                ....*....|....*....|....*.
gi 29611435  76 TPYMTIVAFLV-YFIPFICCWSPYFL 100
Cdd:cd15192 164 LVGLGLMKNLLgFLIPFLIILTCYTL 189

type 2 angiotensin II receptor, member of the class A family of seven-transmembrane G protein-coupled receptors; Angiotensin II (Ang II), the main effector in the renin-angiotensin system, plays a crucial role in the regulation of cardiovascular homeostasis through its type 1 (AT1) and type 2 (AT2) receptors. Ang II contributes to cardiovascular diseases such as hypertension and atherosclerosis via AT1R activation. Ang II increases blood pressure through Gq-mediated activation of phospholipase C, resulting in phosphoinositide (PI) hydrolysis and increased intracellular calcium levels. Through the AT2R, Ang II counteracts the vasoconstrictor action of AT1R and thereby induces vasodilation, sodium excretion, and reduction of blood pressure. Moreover, AT1R promotes cell proliferation, whereas AT2R inhibits proliferation and stimulates cell differentiation. The AT2R is highly expressed during fetal development, however it is scarcely present in adult tissues and is induced in pathological conditions. Generally, the AT1R mediates many actions of Ang II, while the AT2R is involved in the regulation of blood pressure and renal function.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435  12 LYASTYVLVSLSIDRYHAIVYPM-------------IVIAWSLSFLFSIPTLIIFGKRTLSNGEVQ-CWALWPDDSYWTP 77
Cdd:cd15191  84 LFASIFFITCMSVDRYLAVVYPLrsqrrrswqarlvCLLVWVLACLSSLPTFYFRDTYYIEELGVNaCIMAFPNEKYAQW 163

                        90       100
                ....*....|....*....|....*
gi 29611435  78 YMTIV------AFLVYFIPFICCWS 96
Cdd:cd15191 164 SAGLAlmkntlGFLIPLIVIATCYF 188

ecdysis-triggering hormone receptors, member of the class A family of seven-transmembrane G protein-coupled receptors; This subgroup represents the ecdysis-triggering hormone receptors found in insects, which are members of the class A family of seven-transmembrane G-protein coupled receptors. Ecdysis-triggering hormones are vital regulatory signals that govern the stereotypic physiological sequence leading to cuticle shedding in insects. Thus, the ETH signaling system has been a target for the design of more sophisticated insect-selective pest control strategies. Two subtypes of ecdysis-triggering hormone receptor were identified in Drosophila melanogaster. Blood-borne ecdysis-triggering hormone (ETH) activates the behavioral sequence through direct actions on the central nervous system. In insects, ecdysis is thought to be controlled by the interaction between peptide hormones; in particular between ecdysis-triggering hormone (ETH) from the periphery and eclosion hormone (EH) and crustacean cardioactive peptide (CCAP) from the central nervous system. All GPCRs have a common structural architecture comprising of seven-transmembrane (TM) alpha-helices interconnected by three extracellular and three intracellular loops. A general feature of GPCR signaling is agonist-induced conformational changes in the receptors, leading to activation of the heterotrimeric G proteins, which consist of the guanine nucleotide-binding G-alpha subunit and the dimeric G-beta-gamma subunits. The activated G proteins then bind to and activate numerous downstream effector proteins, which generate second messengers that mediate a broad range of cellular and physiological processes.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435   3 VRYLQVVVLLyASTYVLVSLSIDRYHAIVYPM--------------IVIAWSLSFLFSIPTLII--FGKRTLSNGEVQCW 66
Cdd:cd14997  77 VPFVELTVAH-ASVLTILAISFERYYAICHPLqakyvctkrralviIALIWLLALLTSSPVLFIteFKEEDFNDGTPVAV 155

                        90       100
                ....*....|....*....|....*..
gi 29611435  67 ALWPDDSYW-TPYMTIVAFLVYFIPFI 92
Cdd:cd14997 156 CRTPADTFWkVAYILSTIVVFFVVPLA 182

tachykinin receptors and related receptors, member of the class A family of seven-transmembrane G protein-coupled receptors; This group includes the neurokinin/tachykinin receptors and its closely related receptors such as orphan GPR83 and leucokinin-like peptide receptor. The tachykinins are widely distributed throughout the mammalian central and peripheral nervous systems and act as excitatory transmitters on neurons and cells in the gastrointestinal tract. The TKs are characterized by a common five-amino acid C-terminal sequence, Phe-X-Gly-Leu-Met-NH2, where X is a hydrophobic residue. The three major mammalian tachykinins are substance P (SP), neurokinin A (NKA), and neurokinin B (NKB). The physiological actions of tachykinins are mediated through three types of receptors: neurokinin receptor type 1 (NK1R), NK2R, and NK3R. SP is a high-affinity endogenous ligand for NK1R, which interacts with the Gq protein and activates phospholipase C, leading to elevation of intracellular calcium. NK2R is a high-affinity receptor for NKA, the tachykinin neuropeptide substance K. SP and NKA are found in the enteric nervous system and mediate in the regulation of gastrointestinal motility, secretion, vascular permeability, and pain perception. NK3R is activated by its high-affinity ligand, NKB, which is primarily involved in the central nervous system and plays a critical role in the regulation of gonadotropin hormone release and the onset of puberty.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435   2 VVRYLQVVVLLyASTYVLVSLSIDRYHAIVYPM------------IVIAWSLSFLFSIPTLIIFGKRTLSNGE----VQC 65
Cdd:cd15202  75 FSNFAQYCSVH-VSAYTLTAIAVDRYQAIMHPLkprisktkakfiIAVIWTLALAFALPHAICSKLETFKYSEdivrSLC 153

                        90       100
                ....*....|....*....|....*..
gi 29611435  66 WALWPD--DSYWTPYMTIVAFLVYFIP 90
Cdd:cd15202 154 LEDWPEraDLFWKYYDLALFILQYFLP 180

protease-activated receptors, member of the class A family of seven-transmembrane G protein-coupled receptors; This subfamily includes purinergic receptor P2Y8 and protease-activated receptors. P2Y8 (or P2RY8) expression is often increased in leukemia patients, and it plays a role in the pathogenesis of acute leukemia. P2Y8 is phylogenetically closely related to the protease-activated receptors (PARs), which are activated by serine proteases such as thrombin, trypsin, and tryptase. These proteases cleave the extracellular domain of the receptor to form a new N-terminus, which in turn functions as a tethered ligand. The newly-formed tethered ligand binds intramolecularly to activate the receptor and triggers G-protein binding and intracellular signaling. Four different types of the protease-activated receptors have been identified (PAR1-4) and are predominantly expressed in platelets. PAR1, PAR3, and PAR4 are activated by thrombin, whereas PAR2 is activated by trypsin. The PARs are known to couple with several G-proteins including Gi (cAMP inhibitory), G12/13 (Rho and Ras activation), and Gq (calcium signaling) to activate downstream signaling messengers which induces numerous cellular and physiological effects.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435  12 LYASTYVLVSLSIDRYHAIVYPM--------------IVIAWSLSFLFSIPTLIIFGK-RTLSNGEVQCWALWPDD---S 73
Cdd:cd15162  84 MYCSILLLTCISIDRYLAIVHPMghrrlrarryalgtCLAIWLLALLVTLPLYLVKQTiFLPALDITTCHDVLPEQllvG 163

                        90
                ....*....|....*....
gi 29611435  74 YWTPYMTIVAFLVYFIPFI 92
Cdd:cd15162 164 DWFYYFLSLAIVGFLIPFI 182

neuropeptide Y receptor type 5, member of the class A family of seven-transmembrane G protein-coupled receptors; NPY is a 36-amino acid peptide neurotransmitter with a C-terminal tyrosine amide residue that is widely distributed in the brain and the autonomic nervous system of many mammalian species. NPY exerts its functions through five, G-protein coupled receptor subtypes including NPY1R, NPY2R, NPY4R, NPY5R, and NPY6R; however, NPY6R is not functional in humans. NYP receptors are also activated by its two other family members, peptide YY (PYY) and pancreatic polypeptide (PP). They typically couple to G(i) or G(o) proteins, which leads to a decrease in adenylate cyclase activity, thereby decreasing intracellular cAMP levels, and are involved in diverse physiological roles including appetite regulation, circadian rhythm, and anxiety. When NPY signals through NPY2R in concert with NPY5R, it induces angiogenesis and consequently plays an important role in revascularization and wound healing. On the other hand, when NPY acts through NPY1R and NPYR5, it acts as a vascular mitogen, leading to restenosis and atherosclerosis.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435   2 VVRYLQVVVLLyASTYVLVSLSIDRYHAIVYP------------MIVIAWSLSFLFSIPTLII---------FGKRTLSN 60
Cdd:cd15398  75 IVPFLQCVSVM-VSTLMLMSIAIVRYHMIKHPlsnhltanhgyfLLGTVWTLGFTICSPLPVFhkivdlsetFNLESLKN 153

                        90       100       110
                ....*....|....*....|....*....|...
gi 29611435  61 GEVqCWALWPDDSYWTPYMTIVAFLVYFIPFIC 93
Cdd:cd15398 154 KYL-CIESWPSDSYRIAFTISLLFVQYILPLVC 185

somatostatin receptor type 2, member of the class A family of seven-transmembrane G protein-coupled receptors; G protein-coupled somatostatin receptors (SSTRs), which display strong sequence similarity with opioid receptors, binds somatostatin, a polypeptide hormone that regulates a wide variety of physiological such as neurotransmission, endocrine secretion, cell proliferation, and smooth muscle contractility. SSTRs are composed of five distinct subtypes (SSTR1-5) which are encoded by separate genes on different chromosomes. SSTR2 plays critical roles in growth hormone secretion, glucagon secretion, and immune responses. SSTR2 is expressed in the normal human pituitary and in nearly all pituitary growth hormone adenomas.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 29611435  13 YASTYVLVSLSIDRYHAIVYP-------------MIVIA-WSLSFLFSIPTLIIFGKRTlSNGEVQCWALWPDDS--YWT 76
Cdd:cd15971  84 FTSIFCLTVMSIDRYLAVVHPiksakwrkprtakMINMAvWGVSLLVILPIMIYAGVQT-KHGRSSCTIIWPGESsaWYT 162