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Glocova K, Cizek P, Novotny R, Hauptman K, Tichy F. Effect of GnRH agonist deslorelin implant on spermatogenesis and testosterone concentration in Guinea pigs (Cavia aperea porcellus). Theriogenology 2020; 154:232-236. [PMID: 32679355 DOI: 10.1016/j.theriogenology.2020.05.038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 05/27/2020] [Accepted: 05/27/2020] [Indexed: 12/01/2022]
Abstract
Guinea pigs are social animals that are often kept in groups regardless of their gender. Due to reproduction control and male aggressiveness prevention, surgical castration is commonly required. In the present study, we evaluated the effect of GnRH agonist implant (4.7 mg deslorelinum) on the serum testosterone concentration (T) and spermatogenesis in male guinea pigs. Twenty-four animals were divided into two groups. All animals in the first group were neutered (Group 1), animals in the second group (Group 2) were administered the implant subcutaneously and then neutered in one-month intervals. A histological examination was performed when cross sections of seminiferous tubules were assessed. Subsequently, these tubules were divided based on the most developed germ cell observed: spermatogonia, spermatocytes, round spermatids, elongating spermatids and elongated spermatids. The anticipated decrease in testosterone concentration and cessation of spermatogenesis was not achieved. Thus, the results obtained proved the inefficacy of the deslorelin implant in male guinea pigs so the alternative methods of contraception remain the methods of choice.
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Affiliation(s)
- Kristyna Glocova
- Department of Anatomy, Histology & Embryology, Faculty of Veterinary Medicine, University of Veterinary and Pharmaceutical Sciences, Brno, Palackeho 1946/1, 612 42, Czech Republic.
| | - Petr Cizek
- Department of Anatomy, Histology & Embryology, Faculty of Veterinary Medicine, University of Veterinary and Pharmaceutical Sciences, Brno, Palackeho 1946/1, 612 42, Czech Republic
| | - Robert Novotny
- Ruminant & Swine Clinic, Faculty of Veterinary Medicine, University of Veterinary and Pharmaceutical Sciences, Brno, Palackeho 1946/1, 612 42, Czech Republic
| | - Karel Hauptman
- Small Animal Clinic, Faculty of Veterinary Medicine, University of Veterinary and Pharmaceutical Sciences, Brno, Palackeho 1946/1, 612 42, Czech Republic
| | - Frantisek Tichy
- Department of Anatomy, Histology & Embryology, Faculty of Veterinary Medicine, University of Veterinary and Pharmaceutical Sciences, Brno, Palackeho 1946/1, 612 42, Czech Republic
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Bogus-Nowakowska K, Równiak M, Hermanowicz-Sobieraj B, Wasilewska B, Najdzion J, Robak A. Tyrosine hydroxylase-immunoreactivity and its relations with gonadotropin-releasing hormone and neuropeptide Y in the preoptic area of the guinea pig. J Chem Neuroanat 2016; 78:131-139. [PMID: 27650206 DOI: 10.1016/j.jchemneu.2016.09.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 09/13/2016] [Accepted: 09/16/2016] [Indexed: 11/16/2022]
Abstract
The present study examines the distribution of tyrosine hydroxylase (TH) immunoreactivity and its morphological relationships with neuropeptide Y (NPY)- and gonadoliberin (GnRH)-immunoreactive (IR) structures in the preoptic area (POA) of the male guinea pig. Tyrosine hydroxylase was expressed in relatively small population of perikarya and they were mostly observed in the periventricular preoptic nucleus and medial preoptic area. The tyrosine hydroxylase-immunoreactive (TH-IR) fibers were dispersed troughout the whole POA. The highest density of these fibers was observed in the median preoptic nucleus, however, in the periventricular preoptic nucleus and medial preoptic area they were only slightly less numerous. In the lateral preoptic area, the density of TH-IR fibers was moderate. Two morphological types of TH-IR fibers were distinguished: smooth and varicose. Double immunofluorescence staining showed that TH and GnRH overlapped in the guinea pig POA but they never coexisted in the same structures. TH-IR fibers often intersected with GnRH-IR structures and many of them touched the GnRH-IR perikarya or dendrites. NPY wchich was abundantly present in the POA only in fibers showed topographical proximity with TH-IR structures. Althoug TH-IR perikarya and fibers were often touched by NPY-IR fibers, colocalization of TH and NPY in the same structures was very rare. There was only a small population of fibers which contained both NPY and TH. In conclusion, the morphological evidence of contacts between TH- and GnRH-IR nerve structures may be the basis of catecholaminergic control of GnRH release in the preoptic area of the male guinea pig. Moreover, TH-IR neurons were conatcted by NPY-IR fibers and TH and NPY colocalized in some fibers, thus NPY may regulate catecholaminergic neurons in the POA.
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Affiliation(s)
- Krystyna Bogus-Nowakowska
- Department of Comparative Anatomy, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, pl. Łódzki 3, 10-727 Olsztyn, Poland.
| | - Maciej Równiak
- Department of Comparative Anatomy, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, pl. Łódzki 3, 10-727 Olsztyn, Poland
| | - Beata Hermanowicz-Sobieraj
- Department of Comparative Anatomy, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, pl. Łódzki 3, 10-727 Olsztyn, Poland
| | - Barbara Wasilewska
- Department of Comparative Anatomy, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, pl. Łódzki 3, 10-727 Olsztyn, Poland
| | - Janusz Najdzion
- Department of Comparative Anatomy, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, pl. Łódzki 3, 10-727 Olsztyn, Poland
| | - Anna Robak
- Department of Comparative Anatomy, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, pl. Łódzki 3, 10-727 Olsztyn, Poland
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Wu X, Yan M, Wan X, Lian S, Li A. Cloning and tissue expression profiling of theGnRHRgene of the Muscovy duck (Cairina moschata): polymorphism and association with egg-laying performance. Br Poult Sci 2015; 56:164-74. [DOI: 10.1080/00071668.2014.997674] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Abstract
This article reviews ovarian cysts in the guinea pig (Cavia porcellus), a disease commonly associated with symmetric, nonpruritic alopecia of the dorsum and flanks. Relevant anatomy is discussed and current theories of pathogenesis are reviewed. Prevalence, predisposing factors, diagnosis, treatment, and prognosis are presented.
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Affiliation(s)
- Andrew D Bean
- Pet Care Veterinary Hospital, 5201 Virginia Beach Boulevard, Virginia Beach, VA 23462, USA.
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Difference in receptor-binding contributes to difference in biological activity between the unique guinea pig GnRH and mammalian GnRH. Neurosci Lett 2012; 507:124-6. [DOI: 10.1016/j.neulet.2011.11.060] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2011] [Revised: 11/18/2011] [Accepted: 11/29/2011] [Indexed: 11/23/2022]
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Gao CQ, Fraeyman N, Eertmans F, Dhooge W, Kaufman JM. Further evaluation of the biological activity of the unique gonadotropin-releasing hormone peptide in the guinea pig brain. Neurosci Lett 2010; 487:246-9. [PMID: 20970475 DOI: 10.1016/j.neulet.2010.10.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2010] [Revised: 08/24/2010] [Accepted: 10/14/2010] [Indexed: 10/18/2022]
Abstract
In this study we compared the biological activity of a unique form of gonadotropin-releasing hormone (GnRH) in the brain of the guinea pig (gpGnRH) with mammalian GnRH (mGnRH). In gpGnRH, the highly conserved histidine in position 2 (His(2)) and leucine in position 7 (Leu(7)) are substituted by tyrosine and valine, respectively. The gpGnRH was less potent than mGnRH in stimulating the release of luteinizing hormone (LH) in vivo in the guinea pig and displayed only low activity in the rat. The gpGnRH was more rapidly degraded by serum proteolytic enzymes than mGnRH. It is concluded that gpGnRH displays lower biological activity than mGnRH in both rat and guinea pig, which may be due in part to its greater susceptibility to proteolytic degradation besides differences in receptor affinity and/or activation.
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Affiliation(s)
- Chang-Qing Gao
- Department of Endocrinology, Ghent University Hospital, 9000 Ghent, Belgium.
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Kavanaugh SI, Nozaki M, Sower SA. Origins of gonadotropin-releasing hormone (GnRH) in vertebrates: identification of a novel GnRH in a basal vertebrate, the sea lamprey. Endocrinology 2008; 149:3860-9. [PMID: 18436713 PMCID: PMC2488216 DOI: 10.1210/en.2008-0184] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We cloned a cDNA encoding a novel (GnRH), named lamprey GnRH-II, from the sea lamprey, a basal vertebrate. The deduced amino acid sequence of the newly identified lamprey GnRH-II is QHWSHGWFPG. The architecture of the precursor is similar to that reported for other GnRH precursors consisting of a signal peptide, decapeptide, a downstream processing site, and a GnRH-associated peptide; however, the gene for lamprey GnRH-II does not have introns in comparison with the gene organization for all other vertebrate GnRHs. Lamprey GnRH-II precursor transcript was widely expressed in a variety of tissues. In situ hybridization of the brain showed expression and localization of the transcript in the hypothalamus, medulla, and olfactory regions, whereas immunohistochemistry using a specific antiserum showed only GnRH-II cell bodies and processes in the preoptic nucleus/hypothalamus areas. Lamprey GnRH-II was shown to stimulate the hypothalamic-pituitary axis using in vivo and in vitro studies. Lamprey GnRH-II was also shown to activate the inositol phosphate signaling system in COS-7 cells transiently transfected with the lamprey GnRH receptor. These studies provide evidence for a novel lamprey GnRH that has a role as a third hypothalamic GnRH. In summary, the newly discovered lamprey GnRH-II offers a new paradigm of the origin of the vertebrate GnRH family. We hypothesize that due to a genome/gene duplication event, an ancestral gene gave rise to two lineages of GnRHs: the gnathostome GnRH and lamprey GnRH-II.
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Affiliation(s)
- Scott I Kavanaugh
- Department of Biochemistry and Molecular Biology, University of New Hampshire, Durham, New Hampshire 03824, USA
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Yuge S, Yamagami S, Inoue K, Suzuki N, Takei Y. Identification of two functional guanylin receptors in eel: multiple hormone-receptor system for osmoregulation in fish intestine and kidney. Gen Comp Endocrinol 2006; 149:10-20. [PMID: 16753163 DOI: 10.1016/j.ygcen.2006.04.012] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2005] [Revised: 03/27/2006] [Accepted: 04/26/2006] [Indexed: 11/26/2022]
Abstract
Guanylyl cyclase C (GC-C) is a single transmembrane receptor for a family of intestinal hormones, guanylins. In the eel, we previously identified three guanylins, whose gene expression was enhanced in the intestine after transfer from fresh water to seawater. However, only limited information is available about the structure and function of their receptor(s). In the present study, we cloned full-length cDNAs encoding two isoforms of GC-C, named GC-C1 and GC-C2, from eel intestine. The predicted GC-C proteins consisted of extracellular ligand-binding domain, membrane-spanning domain, kinase-like domain and cyclase catalytic domain, in which GC-C-specific sequences were largely conserved. Phylogenetic analyses showed that the cloned membrane GCs are grouped with the GC-C of other vertebrates but not with GC-A and GC-B. However, eel GC-Cs appear to have undergone unique structural evolution compared with other GC-Cs. The three eel guanylins (guanylin, uroguanylin and renoguanylin), but not eel atrial natriuretic peptide, stimulated cGMP production dose-dependently in COS cells expressing either of the cloned cDNAs, providing functional support for assignment as eel guanylin receptors. The potency order for cGMP production was uroguanylin > guanylin > or = renoguanylin for GC-C1; guanylin > or = renoguanylin > uroguanylin for GC-C2. The distinctive ligand selectivity was consistent with the low homology (53%) of the extracellular domain of the two GC-Cs compared with that observed for other domains (74-90%). Both GC-C genes were expressed in the alimentary tract (esophagus, stomach and intestine) and kidney, and their expression was higher in the intestine of seawater-adapted eels than that of freshwater eels just as observed with the guanylin genes. However, the expression of the receptor genes was unchanged for 24h after transfer of eels from fresh water to seawater or vice versa, showing slower response of the receptors to salinity changes than their ligands. Collectively, the multiple guanylin-GC-C system may be involved as a paracrine factor in seawater adaptation at the intestine and kidney of the eel.
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Affiliation(s)
- Shinya Yuge
- Laboratory of Physiology, Ocean Research Institute, The University of Tokyo, 1-15-1, Minamidai, Nakano-ku, Tokyo 164-8639, Japan.
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Guilgur LG, Moncaut NP, Canário AVM, Somoza GM. Evolution of GnRH ligands and receptors in gnathostomata. Comp Biochem Physiol A Mol Integr Physiol 2006; 144:272-83. [PMID: 16716622 DOI: 10.1016/j.cbpa.2006.02.016] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2005] [Revised: 01/19/2006] [Accepted: 02/14/2006] [Indexed: 10/24/2022]
Abstract
Gonadotropin-releasing hormone (GnRH) is the final common signaling molecule used by the brain to regulate reproduction in all vertebrates. Until now, a total of 24 GnRH structural variants have been characterized from vertebrate, protochordate and invertebrate nervous tissue. Almost all vertebrates already investigated have at least two GnRH forms coexisting in the central nervous system. Furthermore, it is now well accepted that three GnRH forms are present both in early and late evolved teleostean fishes. The number and taxonomic distribution of the different GnRH variants also raise questions about the phylogenetic relationships between them. Most of the GnRH phylogenetic analyses are in agreement with the widely accepted idea that the GnRH family can be divided into three main groups. However, the examination of the gnathostome GnRH phylogenetic relationships clearly shows the existence of two main paralogous GnRH lineages: the ''midbrain GnRH" group and the "forebrain GnRH" group. The first one, represented by chicken GnRH-II forms, and the second one composed of two paralogous lineages, the salmon GnRH cluster (only represented in teleostean fish species) and the hypophysotropic GnRH cluster, also present in tetrapods. This analysis suggests that the two forebrain clades share a common precursor and reinforces the idea that the salmon GnRH branch has originated from a duplication of the hypophysotropic lineage. GnRH ligands exert their activity through G protein-coupled receptors of the rhodopsin-like family. As with the ligands, multiple GnRHRs are expressed in individual vertebrate species and phylogenetic analyses have revealed that all vertebrate GnRHRs cluster into three main receptor types. However, new data and a new phylogenetic analysis propose a two GnRHR type model, in which different rounds of gene duplications may have occurred in different groups within each lineage.
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Affiliation(s)
- Leonardo G Guilgur
- Laboratorio de Ictiofisiología y Acuicultura, IIB-INTECH, CONICET-Universidad Nacional de General San Martín, IIB-INTECH, Camino de Circunvalación Laguna Km. 6, CC 164, B7130IWA, Chascomús, Provincia de Buenos Aires, Argentina
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Rispoli LA, Nett TM. Pituitary gonadotropin-releasing hormone (GnRH) receptor: structure, distribution and regulation of expression. Anim Reprod Sci 2005; 88:57-74. [PMID: 15993012 DOI: 10.1016/j.anireprosci.2005.05.004] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Reproduction in mammals is controlled by interactions between the hypothalamus, anterior pituitary and gonads. Interaction of GnRH with its cognate receptor is essential to regulating reproduction. Characterization of the structure, distribution and expression of GnRH receptors (GnRH-R) has furthered our understanding of the physiological consequences of GnRH stimulation of pituitary gonadotropes. Based on the putative topology of the amino acid sequence of the GnRH-R and point mutation studies, key elements of the GnRH-R have been identified to play a role in ligand recognition and binding, G-protein activation and internalization. Normally, reproductive function is mediated by GnRH-R expressed only on the membranes of pituitary gonadotropes. The density of GnRH-R on gonadotropes determines their ability to respond to GnRH. This density is highest just prior to ovulation and likely is important for complete expression of the pre-ovulatory surge of LH. Therefore, knowledge regarding what regulates the density of GnRH-R is essential to understanding changes in pituitary sensitivity to GnRH and ultimately, to expression of the LH surge. Regulation of GnRH-R gene expression is influenced by a multitude of factors including gonadal steroid hormones, inhibin, activin and perhaps most importantly GnRH itself.
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Affiliation(s)
- L A Rispoli
- Department of Biomedical Sciences, Animal Reproduction and Biotechnology Laboratory, Colorado State University, Fort Collins, CO 80523, USA
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Hapgood JP, Sadie H, van Biljon W, Ronacher K. Regulation of expression of mammalian gonadotrophin-releasing hormone receptor genes. J Neuroendocrinol 2005; 17:619-38. [PMID: 16159375 DOI: 10.1111/j.1365-2826.2005.01353.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Gonadotrophin-releasing hormone (GnRH), acting via its cognate GnRH receptor (GnRHR), is the primary regulator of mammalian reproductive function, and hence GnRH analogues are extensively used in the treatment of hormone-dependent diseases, as well as for assisted reproductive techniques. In addition to its established endocrine role in gonadotrophin regulation in the pituitary, evidence is rapidly accumulating to support the expression and functional roles for two forms of GnRHR (GnRHR I and GnRHR II) in multiple and diverse extra-pituitary mammalian tissues and cells. These findings, together with findings indicating that mutations of the GnRHR are linked to the disease hypogonadotrophic hypogonadism and that GnRHRs play a direct role in neuronal migration and reproductive cancers, have presented new therapeutic targets and intensified research into the structure, function and mechanisms of regulation of expression of GnRHR genes. The present review focuses on the current knowledge on tissue-specific and hormonal regulation of transcription of mammalian GnRH receptor genes. Emerging insights, such as the discovery of diverse regulatory mechanisms in pituitary and extra-pituitary cell types, nonclassical mechanisms of steroid regulation, the use of composite elements for cell-specific expression, the increasing profile of hormones involved in regulation, the complexity of kinase pathways that target the GnRHR I gene, as well as species-differences, are highlighted. Although further research is necessary to understand the mechanisms of regulation of expression of GnRHR I and GnRHR II genes, the GnRHR is emerging as a potential target gene for facilitating cross-talk between neuroendocrine, immune and stress-response systems in multiple tissues via autocrine, paracrine and endocrine signalling.
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Affiliation(s)
- J P Hapgood
- Department of Biochemistry, University of Stellenbosch, Matieland, South Africa.
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Tello JA, Rivier JE, Sherwood NM. Tunicate gonadotropin-releasing hormone (GnRH) peptides selectively activate Ciona intestinalis GnRH receptors and the green monkey type II GnRH receptor. Endocrinology 2005; 146:4061-73. [PMID: 15961566 DOI: 10.1210/en.2004-1558] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In vertebrates, GnRH binds to its receptor and stimulates predominantly G(q/11)-mediated signal transduction in gonadotropes. However, little is known about the GnRH receptor and its signaling pathway in tunicates, a group that arose before the vertebrates. Although tunicates have had duplications of a few genes in the last 600 million years, the early vertebrates had duplications of the full genome. Also unknown is the nature of GnRH signaling in the tunicate, which lacks both a pituitary gland and sex steroids. However, we know that tunicates have GnRH peptides because we previously reported six GnRH peptides encoded within the tunicate genome of Ciona intestinalis. Here we clone and sequence cDNAs for four putative GnRH receptors from C. intestinalis. These are the only invertebrate GnRH receptors found to date. Each Ciona GnRH receptor was expressed in COS-7 cells, incubated with each of the six C. intestinalis GnRHs and assayed for a signaling response. GnRH receptors 1, 2, and 3 responded to Ciona GnRH peptides to stimulate intracellular cAMP accumulation. In contrast, only GnRH receptor 1 activated inositol phosphate turnover in response to one of the Ciona GnRHs. The green monkey type II GnRH receptor cDNA was tested as a comparison and a positive control. In conclusion, the four GnRH receptors encoded within the C. intestinalis genome were all transcribed into messenger RNA, but only three of the Ciona GnRH receptors were biologically active in our assays. The Ciona GnRH receptors almost exclusively activated the cAMP pathway.
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Affiliation(s)
- Javier A Tello
- Department of Biology, University of Victoria, P.O. Box 3020 STN CSC, Victoria, British Columbia, Canada V8W 3N5
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Silver MR, Nucci NV, Root AR, Reed KL, Sower SA. Cloning and characterization of a functional type II gonadotropin-releasing hormone receptor with a lengthy carboxy-terminal tail from an ancestral vertebrate, the sea lamprey. Endocrinology 2005; 146:3351-61. [PMID: 15878963 DOI: 10.1210/en.2005-0305] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A full-length transcript encoding a functional type II GnRH receptor was cloned from the pituitary of the sea lamprey, Petromyzon marinus. The current study is the first to identify a pituitary GnRH receptor transcript in an agnathan, which is the oldest vertebrate lineage. The cloned receptor retains the conserved structural features and amino acid motifs of other known GnRH receptors and notably includes a C-terminal intracellular tail of approximately 120 amino acids, the longest C-terminal tail of any vertebrate GnRH receptor identified to date. The lamprey GnRH receptor was shown to activate the inositol phosphate (IP) signaling system; stimulation with either lamprey GnRH-I or lamprey GnRH-III led to dose-dependent responses in transiently transfected COS7 cells. Furthermore, analyses of serially truncated lamprey GnRH receptor mutants indicate perturbations of the C-terminal tail disrupts IP accumulation, however, the tailless lamprey GnRH receptor was not only functional but was also capable of stimulating IP levels equal to wild type. Expression of the receptor transcript was demonstrated in the pituitary and testes using RT-PCR, whereas in situ hybridization showed expression and localization of the transcript in the proximal pars distalis of the pituitary. The phylogenetic placement and structural and functional features of this GnRH receptor suggest that it is representative of an ancestral GnRH receptor. In addition to having an important role in lamprey reproductive processes, the extensive C-terminal tail of this lamprey GnRH receptor may have great significance for understanding the evolutionary change of this vital structural feature within the GnRH receptor family.
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Affiliation(s)
- Matthew R Silver
- Department of Biochemistry and Molecular Biology, University of New Hampshire, Durham, New Hampshire 03824, USA
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