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Li W, Ye C, He M, Ko WKW, Cheng CHK, Chan YW, Wong AOL. Differential involvement of cAMP/PKA-, PLC/PKC- and Ca 2+/calmodulin-dependent pathways in GnRH-induced prolactin secretion and gene expression in grass carp pituitary cells. Front Endocrinol (Lausanne) 2024; 15:1399274. [PMID: 38894746 PMCID: PMC11183098 DOI: 10.3389/fendo.2024.1399274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Accepted: 05/13/2024] [Indexed: 06/21/2024] Open
Abstract
Gonadotropin-releasing hormone (GnRH) is a key stimulator for gonadotropin secretion in the pituitary and its pivotal role in reproduction is well conserved in vertebrates. In fish models, GnRH can also induce prolactin (PRL) release, but little is known for the corresponding effect on PRL gene expression as well as the post-receptor signalling involved. Using grass carp as a model, the functional role of GnRH and its underlying signal transduction for PRL regulation were examined at the pituitary level. Using laser capture microdissection coupled with RT-PCR, GnRH receptor expression could be located in carp lactotrophs. In primary cell culture prepared from grass carp pituitaries, the native forms of GnRH, GnRH2 and GnRH3, as well as the GnRH agonist [D-Arg6, Pro9, NEt]-sGnRH were all effective in elevating PRL secretion, PRL mRNA level, PRL cell content and total production. In pituitary cells prepared from the rostral pars distalis, the region in the carp pituitary enriched with lactotrophs, GnRH not only increased cAMP synthesis with parallel CREB phosphorylation and nuclear translocation but also induced a rapid rise in cytosolic Ca2+ by Ca2+ influx via L-type voltage-sensitive Ca2+ channel (VSCC) with subsequent CaM expression and NFAT2 dephosphorylation. In carp pituitary cells prepared from whole pituitaries, GnRH-induced PRL secretion was reduced/negated by inhibiting cAMP/PKA, PLC/PKC and Ca2+/CaM/CaMK-II pathways but not the signalling events via IP3 and CaN/NFAT. The corresponding effect on PRL mRNA expression, however, was blocked by inhibiting cAMP/PKA/CREB/CBP and Ca2+/CaM/CaN/NFAT2 signalling but not PLC/IP3/PKC pathway. At the pituitary cell level, activation of cAMP/PKA pathway could also induce CaM expression and Ca2+ influx via VSCC with parallel rises in PRL release and gene expression in a Ca2+/CaM-dependent manner. These findings, as a whole, suggest that the cAMP/PKA-, PLC/PKC- and Ca2+/CaM-dependent cascades are differentially involved in GnRH-induced PRL secretion and PRL transcript expression in carp lactotrophs. During the process, a functional crosstalk between the cAMP/PKA- and Ca2+/CaM-dependent pathways may occur with PRL release linked with CaMK-II and PKC activation and PRL gene transcription caused by nuclear action of CREB/CBP and CaN/NFAT2 signalling.
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Affiliation(s)
- Wensheng Li
- School of Biological Sciences, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
- School of Life Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Cheng Ye
- School of Biological Sciences, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
| | - Mulan He
- School of Biological Sciences, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
| | - Wendy K. W. Ko
- School of Biological Sciences, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
| | - Christopher H. K. Cheng
- School of Biomedical Sciences, Chinese University of Hong Kong, Hong Kong, Hong Kong SAR, China
| | - Ying Wai Chan
- School of Biological Sciences, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
| | - Anderson O. L. Wong
- School of Biological Sciences, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
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Wang M, Luo J, Dai L, Feng M, Cao X, Zhang J, Wan Y, Yang X, Wang Y. Foxp2 deficiency impairs reproduction by modulating the hypothalamic-pituitary-gonadal axis in zebrafish†. Biol Reprod 2024; 110:908-923. [PMID: 38288660 DOI: 10.1093/biolre/ioae019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Revised: 01/20/2024] [Accepted: 01/23/2024] [Indexed: 02/29/2024] Open
Abstract
FOXP2 was initially characterized as a transcription factor linked to speech and language disorders. Single-cell RNA sequencing reveals that Foxp2 is enriched in the gonadotrope cluster of the pituitary gland and colocalized with the hormones LHB and FSHB in chickens and mice, implying that FOXP2 might be associated with reproduction in vertebrates. Herein, we investigated the roles of foxp2 in reproduction in a Foxp2-deficient zebrafish model. The results indicated that the loss of Foxp2 inhibits courtship behavior in adult male zebrafish. Notably, Foxp2 deficiency disrupts gonad development, leading to retardation of follicle development and a decrease in oocytes in females at the full-growth stage, among other phenotypes. The transcriptome analysis (RNA-seq) also revealed that differentially expressed genes clustered into the estrogen signaling and ovarian steroidogenesis-related signaling pathways. In addition, we found that Foxp2 deficiency could modulate the hypothalamic-pituitary-gonadal axis, especially the regulation of lhb and fshb expression, in zebrafish. In contrast, the injection of human chorionic gonadotropin, a specific LH agonist, partially rescues Foxp2-impaired reproduction in zebrafish, suggesting that Foxp2 plays an important role in the regulation of reproduction via the hypothalamic-pituitary-gonadal axis in zebrafish. Thus, our findings reveal a new role for Foxp2 in the regulation of reproduction in vertebrates.
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Affiliation(s)
- Maya Wang
- Key Laboratory of Bioresources and Eco-environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, China
| | - Juanjuan Luo
- Key Laboratory of Bioresources and Eco-environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, China
| | - Lu Dai
- Key Laboratory of Bioresources and Eco-environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, China
| | - Meilan Feng
- Key Laboratory of Bioresources and Eco-environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, China
| | - Xiaoqian Cao
- Key Laboratory of Bioresources and Eco-environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, China
| | - Jiannan Zhang
- Key Laboratory of Bioresources and Eco-environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, China
| | - Yiping Wan
- Key Laboratory of Bioresources and Eco-environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, China
| | - Xiaojun Yang
- Shantou University Medical College, Shantou, China
| | - Yajun Wang
- Key Laboratory of Bioresources and Eco-environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, China
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Byun JH, Hyeon JY, Hettiarachchi SA, Udagawa S, Mahardini A, Kim JM, Hur SP, Takemura A. Effects of dopamine and melatonin treatment on the expression of the genes associated with artificially induced sexual maturation in Japanese eel, Anguilla japonica. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY 2024; 341:389-399. [PMID: 38334250 DOI: 10.1002/jez.2788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 01/14/2024] [Accepted: 01/18/2024] [Indexed: 02/10/2024]
Abstract
Japanese eel (Anguilla japonica) is a commercially important fish species in Asia. Understanding factors like photoperiod, temperature, and lunar cycles is crucial for successful aquaculture and managing its reproduction. Melatonin and dopamine (DA) are essential for regulating reproduction in vertebrates, including fish. This study investigated the effects of melatonin and DA on the reproductive system of mature male Japanese eels to better understand reproductive regulation in fish. To clarify the effects of these hormones on sexual maturation in eels, a critical stage in the reproductive process, sexual maturation was induced by injecting human chorionic gonadotropin, which stimulates the production of sex hormones. To check the effect of melatonin and DA on sexual maturation, DA, melatonin, and DA + domperidone were intraperitoneally injected into fish from each group (six per treatment) at a dose of 1 mg/kg body weight. The fish were then examined using quantitative RT-PCR by comparing the messenger RNA level of reproduction-related genes (gonadotropin releasing hormone 1; gnrh1, gonadotropin releasing hormone 2; gnrh2, follicle stimulating hormone; fshβ, luteinizing hormone; lhβ and DA receptor 2b; d2b), involved in the gonadotropic axis in eels, to those that received a control injection. The results indicate significant differences in the expression levels of gnrh1, gnrh2 and d2b in the brain and d2b, fshβ, lhβ in the pituitary at different stages of sexual maturation. Melatonin appears to enhance the production of sex gonadotropins, whereas DA inhibits them. These findings suggest an interaction between melatonin and DA in regulating reproduction in Japanese eels.
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Affiliation(s)
- Jun-Hwan Byun
- Department of Fisheries Biology, College of Fisheries Sciences, Pukyong National University, Busan, South Korea
| | - Ji-Yeon Hyeon
- Division of Polar Life Science, Korea Polar Research Institute, Incheon, South Korea
| | | | - Shingo Udagawa
- Department of Co-Creation Management, Organization for Research Promotion, University of the Ryukyus, Okinawa, Japan
| | - Angka Mahardini
- Department of Marine Science, Faculty of Science, Diponegoro University, Semarang, Indonesia
| | - Jong-Myoung Kim
- Department of Fisheries Biology, College of Fisheries Sciences, Pukyong National University, Busan, South Korea
| | - Sung-Pyo Hur
- Department of Marine Life Science, Jeju National University, Jeju, South Korea
| | - Akihiro Takemura
- Department of Chemistry, Biology, and Marine Science, University of the Ryukyus, Okinawa, Japan
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Kumar TP, Gireesh-Babu P, Vasudevan D, Pavan-Kumar A, Chaudhari A. Characterization of Kiss/Kissr system and expression profiling through developmental stages indicate kiss1 to be the active isotype in Clarias magur. FISH PHYSIOLOGY AND BIOCHEMISTRY 2024:10.1007/s10695-024-01343-4. [PMID: 38647980 DOI: 10.1007/s10695-024-01343-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 04/05/2024] [Indexed: 04/25/2024]
Abstract
Kisspeptin (Kiss) and kisspeptin receptor (Kissr) system is a key regulator of GnRH expression in several vertebrates. The Indian catfish, Clarias magur, is popular in the Indian sub-continent, and a neo-type of the Asian catfish, C. batrachus. Catfish breeding is constrained as males do not release milt captivity with/without stimulation. Magur Kiss/Kissr system comprising of kiss1, kiss2, kissr1, and kissr2 genes was characterized for the first time. Full-length mRNA was sequenced using RACE PCR. Neighbor-joining tree of predicted proteins shows one clade of teleost orthologs. Magur whole genome (NCBI GenBank) has single copies of each gene, though yet unannotated/misannotated. Anomalies in the nomenclature of earlier sequences in GenBank were noted. Relative gene expression was profiled during various ontogenic stages, in six tissues including brain and gonads at maturity, and also in brains and gonads of premature and spent fish. Expression of gnrh1, gnrhr1, and gnrhr2 was estimated concomitantly. The kiss1 was the first to be twofold upregulated (P < 0.05) at 12 h post fertilization. Kiss/Kissr genes expressed primarily in the brain, ovary, and testis. Though kiss2 was 10 times higher than kiss1, only kiss1 showed significant modulation across stages and appears to be the active isotype that regulates GnRH in magur.
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Affiliation(s)
- Thushar P Kumar
- ICAR-Central Institute of Fisheries Education, Mumbai, 400061, India
| | | | - Dileep Vasudevan
- RGCB-Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, 695014, India
| | - Annam Pavan-Kumar
- ICAR-Central Institute of Fisheries Education, Mumbai, 400061, India
| | - Aparna Chaudhari
- ICAR-Central Institute of Fisheries Education, Mumbai, 400061, India.
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Fujimori C, Sugimoto K, Ishida M, Yang C, Kayo D, Tomihara S, Sano K, Akazome Y, Oka Y, Kanda S. Long-lasting redundant gnrh1/3 expression in GnRH neurons enabled apparent switching of paralog usage during evolution. iScience 2024; 27:109304. [PMID: 38464591 PMCID: PMC10924128 DOI: 10.1016/j.isci.2024.109304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 12/08/2023] [Accepted: 02/16/2024] [Indexed: 03/12/2024] Open
Abstract
Expressed subtype of paralogous genes in functionally homologous cells sometimes show differences across species, the reasons for which have not been explained. The present study examined hypophysiotropic gonadotropin-releasing hormone (GnRH) neurons in vertebrates to investigate this mechanism. These neurons express either gnrh1 or gnrh3 paralogs, depending on the species, and apparent switching of the expressed paralogs in them occurred at least four times in vertebrate evolution. First, we found redundant expression of gnrh1 and gnrh3 in a single neuron in piranha and hypothesized that it may represent an ancestral GnRH system. Moreover, the gnrh1/gnrh3 enhancer of piranha induced reporter RFP/GFP co-expression in a single hypophysiotropic GnRH neuron in both zebrafish and medaka, whose GnRH neurons only express either gnrh3 or gnrh1. Thus, we propose that redundant expression of gnrh1/3 of relatively recent common ancestors may be the key to apparent switching of the paralog usage among present-day species.
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Affiliation(s)
- Chika Fujimori
- Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa, Chiba, Japan
- Optics and Imaging Facility, National Institute for Basic Biology, Okazaki, Aichi, Japan
| | - Kohei Sugimoto
- Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa, Chiba, Japan
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Mio Ishida
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Christopher Yang
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
- Department of Neuroscience, Johns Hopkins University, Baltimore, MD, USA
| | - Daichi Kayo
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
- Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Soma Tomihara
- Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa, Chiba, Japan
- Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, Japan
| | - Kaori Sano
- Department of Chemistry, Faculty of Science, Josai University, Sakado, Saitama, Japan
| | - Yasuhisa Akazome
- Department of Anatomy, St. Marianna University School of Medicine, Kawasaki, Kanagawa, Japan
| | - Yoshitaka Oka
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Shinji Kanda
- Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa, Chiba, Japan
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
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6
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Oka Y. Neural Control of Sexual Behavior in Fish. Zoolog Sci 2023; 40:128-140. [PMID: 37042692 DOI: 10.2108/zs220108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 01/09/2023] [Indexed: 03/17/2023]
Abstract
Many vertebrate species show breeding periods and exhibit series of characteristic species-specific sexual behaviors only during the breeding period. Here, secretion of gonadal sex hormones from the mature gonads has been considered to facilitate sexual behaviors. Thus, the sexual behavior has long been considered to be regulated by neural and hormonal mechanisms. In this review, we discuss recent progress in the study of neural control mechanisms of sexual behavior with a focus on studies using fish, which have often been the favorite animals used by many researchers who study instinctive animal behaviors. We first discuss control mechanisms of sexual behaviors by sex steroids in relation to the anatomical studies of sex steroid-concentrating neurons in various vertebrate brains, which are abundantly distributed in evolutionarily conserved areas such as preoptic area (POA) and anterior hypothalamus. We then focus on another brain area called the ventral telencephalic area, which has also been suggested to contain sex steroid-concentrating neurons and has been implicated in the control of sexual behaviors, especially in teleosts. We also discuss control of sex-specific behaviors and sexual preference influenced by estrogenic signals or by olfactory/pheromonal signals. Finally, we briefly summarize research on the modulatory control of motivation for sexual behaviors by a group of peptidergic neurons called terminal nerve gonadotropin-releasing hormone (TN-GnRH) neurons, which are known to be especially developed in fishes among various vertebrate species.
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Affiliation(s)
- Yoshitaka Oka
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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7
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Tanaka A, Umatani C, Oka Y. Acetylcholine Inhibits Spontaneous Firing Activity of Terminal Nerve GnRH Neurons in Medaka. Zoolog Sci 2023; 40:151-159. [PMID: 37042694 DOI: 10.2108/zs220070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 01/04/2023] [Indexed: 03/17/2023]
Abstract
Vertebrates generally possess hypophysiotropic and non-hypophysiotropic gonadotropin releasing hormone (GnRH) neurons. The terminal nerve (TN) GnRH neurons are known to belong to the non-hypophysiotropic neurons and have been suggested to modulate sexual behaviors. These neurons show spontaneous pacemaker firing activity and release neuropeptides GnRH and neuropeptide FF. Since the spontaneous firing activities of peptidergic neurons, including GnRH neurons, are believed to play important roles in the release of neuropeptides, understanding the regulatory mechanisms of these spontaneous firing activities is important. Here, we analyzed firing activities of the TN-GnRH neurons in medaka during application of acetylcholine (ACh), which is one of the essential neuromodulators in the brain. Whole cell patch clamp recording of TN-GnRH neurons demonstrated that ACh induces hyperpolarization and inhibits their pacemaker firing. Electrophysiological analysis using an antagonist for acetylcholine receptors and in situ hybridization analysis showed that firing of TN-GnRH neurons is inhibited via M2-type muscarinic acetylcholine receptor. These findings, taken together with literature from several other fish species (including teleosts and elasmobranchs), indicate that ACh may generally play an inhibitory role in modulating spontaneous activities of TN-GnRH neurons and thereby sexual behaviors in fish.
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Affiliation(s)
- Aiki Tanaka
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Chie Umatani
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yoshitaka Oka
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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Ogawa S, Yamamoto N, Hagio H, Oka Y, Parhar IS. Multiple gonadotropin-releasing hormone systems in non-mammalian vertebrates: Ontogeny, anatomy, and physiology. J Neuroendocrinol 2022; 34:e13068. [PMID: 34931380 DOI: 10.1111/jne.13068] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 11/17/2021] [Accepted: 11/19/2021] [Indexed: 01/08/2023]
Abstract
Three paralogous genes for gonadotropin-releasing hormone (GnRH; gnrh1, gnrh2, and gnrh3) and GnRH receptors exist in non-mammalian vertebrates. However, there are some vertebrate species in which one or two of these paralogous genes have become non-functional during evolution. The developmental migration of GnRH neurons in the brain is evolutionarily conserved in mammals, reptiles, birds, amphibians, and jawed teleost fish. The three GnRH paralogs have specific expression patterns in the brain and originate from multiple sites. In acanthopterygian teleosts (medaka, cichlid, etc.), the preoptic area (POA)-GnRH1 and terminal nerve (TN)-GnRH3 neuronal types originate from the olfactory regions. In other fish species (zebrafish, goldfish and salmon) with only two GnRH paralogs (GnRH2 and GnRH3), the TN- and POA-GnRH3 neuronal types share the same olfactory origin. However, the developmental origin of midbrain (MB)-GnRH2 neurons is debatable between mesencephalic or neural crest site. Each GnRH system has distinctive anatomical and physiological characteristics, and functions differently. The POA-GnRH1 neurons are hypophysiotropic in nature and function in the neuroendocrine control of reproduction. The non-hypophysiotropic GnRH2/GnRH3 neurons probably play neuromodulatory roles in metabolism (MB-GnRH2) and the control of motivational state for sexual behavior (TN-GnRH3).
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Affiliation(s)
- Satoshi Ogawa
- Jeffrey Cheah School of Medicine & Health Sciences, Monash University Malaysia, Selangor, Malaysia
| | - Naoyuki Yamamoto
- Laboratory of Fish Biology, Department of Animal Sciences, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - Hanako Hagio
- Laboratory of Fish Biology, Department of Animal Sciences, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
- Institute for Advanced Research, Nagoya University, Nagoya, Japan
| | - Yoshitaka Oka
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Ishwar S Parhar
- Jeffrey Cheah School of Medicine & Health Sciences, Monash University Malaysia, Selangor, Malaysia
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Song JA, Park HS, Park YS, Kho KH, Choi CY. Exogenous cortisol and red light irradiation affect reproductive parameters in the goldfish Carassius auratus. FISH PHYSIOLOGY AND BIOCHEMISTRY 2021; 47:1711-1724. [PMID: 34480244 DOI: 10.1007/s10695-021-01013-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 08/27/2021] [Indexed: 06/13/2023]
Abstract
Reproductive hormones play essential roles in the control of reproduction and gonadal maturation in fish. The purpose of this study was to determine the effects of cortisol administration (10 µg/g or 50 µg/g) or red light irradiation at two intensities (0.5 W/m2 or 1.0 W/m2) on the reproductive hormones in goldfish (Carassius auratus). The effects of different treatments were analyzed by determining the mRNA expression levels of gonadotropin-inhibitory hormone receptor (GnIH-R), chicken gonadotropin-releasing hormone (cGnRH-II), salmon GnRH (sGnRH), FSHβ, LHβ, and plasma testosterone and the level of 17β-estradiol for 48 h. Additionally, by double immunofluorescence staining, we detected the expression of both GnIH and GnRH in the diencephalons of goldfish brains. The mRNA expression of GnIH-R was significantly higher in the cortisol group and red light-irradiated group from 3 to 48 h than in the control group. Additionally, the mRNA levels of cGnRH-II, sGnRH, FSHβ, LHβ, testosterone, and 17β-estradiol were significantly lower in the cortisol group than in the other groups from 3 to 48 h. These results indicated that both cortisol and red light-emitting diode (LED) light increased GnIH expression and inhibited GnRH expression. In particular, red light irradiation suppressed reproductive responses as much as the cortisol treatment at 48 h. Thus, it could be an alternative method for suppressing reproductive responses in future aquacultures.
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Affiliation(s)
- Jin Ah Song
- Division of Marine BioScience, National Korea Maritime and Ocean University, Busan, 49112, Korea
| | - Heung-Sik Park
- Marine Ecosystem and Biological Research Center, KIOST, Busan, 49111, Korea
| | | | - Kang Hee Kho
- Department of Fisheries Science, Chonnam National University, Yeosu, 59626, Korea.
| | - Cheol Young Choi
- Division of Marine BioScience, National Korea Maritime and Ocean University, Busan, 49112, Korea.
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Maruska KP, Butler JM. Reproductive- and Social-State Plasticity of Multiple Sensory Systems in a Cichlid Fish. Integr Comp Biol 2021; 61:249-268. [PMID: 33963407 DOI: 10.1093/icb/icab062] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Intra- and inter-sexual communications are vital to the survival and reproductive success of animals. In species that cycle in and out of breeding or other physiological condition, sensory function can be modulated to optimize communication at crucial times. Little is known, however, about how widespread this sensory plasticity is across taxa, whether it occurs in multiple senses or both sexes within a species, and what potential modulatory substances and substrates are involved. Thus, studying modulation of sensory communication in a single species can provide valuable insights for understanding how sensory abilities can be altered to optimize detection of salient signals in different sensory channels and social contexts. The African cichlid fish Astatotilapia burtoni uses multimodal communication in social contexts such as courtship, territoriality, and parental care and shows plasticity in sensory abilities. In this review, we synthesize what is known about how visual, acoustic, and chemosensory communication is used in A. burtoni in inter- and intra-specific social contexts, how sensory funtion is modulated by an individual's reproductive, metabolic, and social state, and discuss evidence for plasticity in potential modulators that may contribute to changes in sensory abilities and behaviors. Sensory plasticity in females is primarily associated with the natural reproductive cycle and functions to improve detection of courtship signals (visual, auditory, chemosensory, and likely mechanosensory) from high-quality males for reproduction. Plasticity in male sensory abilities seems to function in altering their ability to detect the status of other males in the service of territory ownership and future reproductive opportunities. Changes in different classes of potential modulators or their receptors (steroids, neuropeptides, and biogenic amines) occur at both peripheral sensory organs (eye, inner ear, and olfactory epithelium) and central visual, olfactory, and auditory processing regions, suggesting complex mechanisms contributing to plasticity of sensory function. This type of sensory plasticity revealed in males and females of A. burtoni is likely more widespread among diverse animals than currently realized, and future studies should take an integrative and comparative approach to better understand the proximate and ultimate mechanisms modulating communication abilities across taxa.
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Affiliation(s)
- Karen P Maruska
- Department of Biological Sciences, Louisiana State University, 202 Life Sciences Bldg., Baton Rouge, LA 70803, USA
| | - Julie M Butler
- Department of Biological Sciences, Louisiana State University, 202 Life Sciences Bldg., Baton Rouge, LA 70803, USA
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11
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Targeted mutation of secretogranin-2 disrupts sexual behavior and reproduction in zebrafish. Proc Natl Acad Sci U S A 2020; 117:12772-12783. [PMID: 32467166 DOI: 10.1073/pnas.2002004117] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The luteinizing hormone surge is essential for fertility as it triggers ovulation in females and sperm release in males. We previously reported that secretoneurin-a, a neuropeptide derived from the processing of secretogranin-2a (Scg2a), stimulates luteinizing hormone release, suggesting a role in reproduction. Here we provide evidence that mutation of the scg2a and scg2b genes using TALENs in zebrafish reduces sexual behavior, ovulation, oviposition, and fertility. Large-scale spawning within-line crossings (n = 82 to 101) were conducted. Wild-type (WT) males paired with WT females successfully spawned in 62% of the breeding trials. Spawning success was reduced to 37% (P = 0.006), 44% (P = 0.0169), and 6% (P < 0.0001) for scg2a -/- , scg2b -/- , and scg2a -/- ;scg2b -/- mutants, respectively. Comprehensive video analysis indicates that scg2a -/- ;scg2b -/- mutation reduces all male courtship behaviors. Spawning success was 47% in saline-injected WT controls compared to 11% in saline-injected scg2a -/- ;scg2b -/- double mutants. For these mutants, spawning success increased 3-fold following a single intraperitoneal (i.p.) injection of synthetic secretoneurin-a (P = 0.0403) and increased 3.5-fold with injection of human chorionic gonadotropin (hCG). Embryonic survival at 24 h remained on average lower in scg2a -/- ;scg2b -/- fish compared to WT injected with secretoneurin-a (P < 0.001). Significant reductions in the expression of gonadotropin-releasing hormone 3 in the hypothalamus, and luteinizing hormone beta and glycoprotein alpha subunits in the pituitary provide evidence for disrupted hypothalamo-pituitary function in scg2a and scg2b mutant fish. Our results indicate that secretogranin-2 is required for optimal reproductive function and support the hypothesis that secretoneurin is a reproductive hormone.
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Chehade C, Amaral FG, Branco GS, Cassel M, De Jesus LWO, Costa FG, Bordin SA, Moreira RG, Borella MI. Molecular characterization of different preproGnRHs in Astyanax altiparanae (Characiformes): Effects of GnRH on female reproduction. Mol Reprod Dev 2020; 87:720-734. [PMID: 32418283 DOI: 10.1002/mrd.23351] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 05/03/2020] [Indexed: 12/13/2022]
Abstract
Gonadotropin-releasing hormone (GnRH) is a key molecule in the initiation of the hypothalamic-pituitary-gonadal axis. Thus, knowledge about GnRH may contribute to the effectiveness of species reproduction. Using a Neotropical tetra Astyanax altiparanae as a fish model species, the GnRH forms were characterized at the molecular level and the role of injected GnRHs in vivo was evaluated. The full-length complementary DNA (cDNA) sequences of preproGnRH2 (612 bp) and preproGnRH3 (407 bp) of A. altiparanae were obtained, and the GnRH1 form was not detected. The cDNA sequences of preproGnRH2 and preproGnRH3 were found to be conserved, but a change in the amino acid at position 8 of the GnRH3 decapeptide of A. altiparanae was observed. All the injected GnRHs stimulated lhβ messenger RNA (mRNA) expression but not fshβ mRNA expression, and only GnRH2 was able to increase maturation-inducing steroid (MIS) levels and possibly stimulate oocyte release. Furthermore, only GnRH2 was able to start the entire reproductive hormonal cascade and induce spawning.
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Affiliation(s)
- Chayrra Chehade
- Fish Endocrinology Laboratory, Department of Cell and Developmental Biology, Biomedical Sciences Institute, University of São Paulo (USP), São Paulo, Brazil
| | - Fernanda G Amaral
- Department of Physiology and Biophysics, Biomedical Sciences Institute, University of São Paulo (USP), São Paulo, São Paulo, Brazil.,Department of Physiology, Federal University of São Paulo (UNIFESP), São Paulo, São Paulo, Brazil
| | - Giovana S Branco
- Fish Endocrinology Laboratory, Department of Cell and Developmental Biology, Biomedical Sciences Institute, University of São Paulo (USP), São Paulo, Brazil
| | - Mônica Cassel
- Department of Education - Bachelor of Science in Animal Science, Mato Grosso Federal Institute of Education, Science, and Technology (IFMT)-Alta Floresta Campus, Alta Floresta, Mato Grosso, Brazil
| | - Lázaro W O De Jesus
- Laboratory of Applied Animal Morphophysiology, Department of Histology and Embryology, Institute of Biological Sciences and Health, Federal University of Alagoas (UFAL), Maceio, Alagoas, Brazil
| | - Fabiano G Costa
- Department of Biological Sciences, State University of Northern Paraná (UENP), Jacarezinho, Paraná, Brazil
| | - Silvana A Bordin
- Department of Physiology and Biophysics, Biomedical Sciences Institute, University of São Paulo (USP), São Paulo, São Paulo, Brazil
| | - Renata G Moreira
- Laboratory of Metabolism and Reproduction of Aquatic Organisms, Department of Physiology, Institute of Biosciences, University of São Paulo (USP), São Paulo, São Paulo, Brazil
| | - Maria I Borella
- Fish Endocrinology Laboratory, Department of Cell and Developmental Biology, Biomedical Sciences Institute, University of São Paulo (USP), São Paulo, Brazil
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Imamura S, Hur SP, Takeuchi Y, Badruzzaman M, Mahardini A, Rizky D, Takemura A. The mRNA expression patterns of kisspeptins, GnRHs, and gonadotropins in the brain and pituitary gland of a tropical damselfish, Chrysiptera cyanea, during the reproductive cycle. FISH PHYSIOLOGY AND BIOCHEMISTRY 2020; 46:277-291. [PMID: 31705423 DOI: 10.1007/s10695-019-00715-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 10/09/2019] [Indexed: 06/10/2023]
Abstract
The sapphire devil (Chrysiptera cyanea) is a tropical damselfish that undergoes active reproduction under long-day conditions. To elucidate the physiological regulation of the brain-pituitary-gonadal axis in female sapphire devil, we cloned and characterized the genes of two kisspeptins (kiss1 and kiss2), three gonadotropin-releasing hormones (gnrh1, gnrh2, gnrh3), and the β-subunit of two gonadotropins (fshβ and lhβ) and investigated the gene expression changes during ovarian development. Quantitative polymerase chain reaction analyses in various brain parts revealed high expression levels of kiss1, kiss2, and gnrh2 in the diencephalon; gnrh2 and gnrh3 in the telencephalon; and fshβ and lhβ in the pituitary. In situ hybridization (ISH) analyses revealed positive signals of kiss1 in the dorsal and ventral habenular nucleus and of kiss2 in the dorsal and ventral parts of the nucleus of the lateral recess. This analysis showed gnrh1 expression in the preoptic area (POA), suggesting that GnRH1 plays a stimulating role in the secretion of gonadotropins from the pituitary of the sapphire devil. High transcription levels of kiss1, kiss2, gnrh1, gnrh2, fshβ, and lhβ were observed in the brain during the late vitellogenic stage, suggesting their involvement in the physiological processes of vitellogenesis. Immersion of fish in estradiol-17β (E2)-containing seawater resulted in increased expression of kiss2 and gnrh1 in their brains. This study showed that kiss-expressing neurons in the diencephalon are influenced by E2, leading to upregulation of gnrh1 in the POA and of fshβ and lhβ in the pituitary during vitellogenesis.
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Affiliation(s)
- Satoshi Imamura
- Department of Chemistry, Biology and Marine Science, Faculty of Science, University of the Ryukyus, Senbaru 1, Nishihara, Okinawa, 903-0213, Japan
| | - Sung-Pyo Hur
- Jeju Research Institute, Korea Institute of Ocean Science & Technology, Jeju, 63349, South Korea
| | - Yuki Takeuchi
- Department of Chemistry, Biology and Marine Science, Faculty of Science, University of the Ryukyus, Senbaru 1, Nishihara, Okinawa, 903-0213, Japan
- Okinawa Institute of Science and Technology Graduate School, 1919-1 Tancha, Onna, Okinawa, 904-0495, Japan
| | - Muhammad Badruzzaman
- Department of Chemistry, Biology and Marine Science, Faculty of Science, University of the Ryukyus, Senbaru 1, Nishihara, Okinawa, 903-0213, Japan
- Department of Biochemistry and Molecular Biology, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Salna, Gazipur, 1706, Bangladesh
| | - Angka Mahardini
- Department of Chemistry, Biology and Marine Science, Faculty of Science, University of the Ryukyus, Senbaru 1, Nishihara, Okinawa, 903-0213, Japan
| | - Dinda Rizky
- Department of Chemistry, Biology and Marine Science, Faculty of Science, University of the Ryukyus, Senbaru 1, Nishihara, Okinawa, 903-0213, Japan
| | - Akihiro Takemura
- Department of Chemistry, Biology and Marine Science, Faculty of Science, University of the Ryukyus, Senbaru 1, Nishihara, Okinawa, 903-0213, Japan.
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Kanda S. Evolution of the regulatory mechanisms for the hypothalamic-pituitary-gonadal axis in vertebrates-hypothesis from a comparative view. Gen Comp Endocrinol 2019; 284:113075. [PMID: 30500374 DOI: 10.1016/j.ygcen.2018.11.014] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 11/26/2018] [Accepted: 11/26/2018] [Indexed: 12/26/2022]
Abstract
Reproduction is regulated by the hypothalamic-pituitary-gonadal (HPG) axis in vertebrates. In addition to wealth of knowledge in mammals, recent studies in non-mammalian species, especially teleosts, have provided evidence that some of the components in the HPG axis are conserved in bony vertebrates. On the other hand, from the comparisons of the recent accumulating knowledge between mammals and teleosts, unique characteristics of the regulatory system in each group have been unveiled. A hypophysiotropic neurotransmitter/hormone, gonadotropin releasing hormone (GnRH), pituitary gonadotropins, follicle stimulating hormone (FSH), and luteinizing hormone (LH) were proven to be common important elements of the HPG axis in teleosts and mammals, although the roles of each vary. Conversely, there are some modulators of GnRH or gonadotropins that are not common to all vertebrates. In this review, I will introduce the mechanism for HPG axis regulation in mammals and teleosts, and describe their evolution from a hypothetical common ancestor.
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Affiliation(s)
- Shinji Kanda
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan.
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15
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Wang W, Chen J, Fang Y, Wang B, Zou Q, Wang L, Zhang W, Huang X, Lv H, Zhang C, Wang K. Identification of gnrh2 and gnrh3 and their expression during brood pouch growth and short-term benzo(a)pyrene exposure in lined seahorse (Hippocampus erectus). Comp Biochem Physiol C Toxicol Pharmacol 2019; 225:108579. [PMID: 31386905 DOI: 10.1016/j.cbpc.2019.108579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 07/25/2019] [Accepted: 07/26/2019] [Indexed: 11/16/2022]
Abstract
Gonadotropin-releasing hormones (GnRH) regulate gonadal growth of teleosts. Benzo(a)pyrene (BaP) functions as a reproductive endocrine disruptor. Furthermore, endocrine regulation on brood pouch growth of Syngnathidaes is elusive. To better understand the role of GnRH in brood pouch growth and effects of BaP on reproductive endocrine in lined seahorse (Hippocampus erectus), gnrh2 and gnrh3 genes were identified. Results showed that lined seahorse GnRH2 and GnRH3 precursors included the conservative tripartite structure and their transcripts highly expressed in brain as other teleosts. Expression profiles of gnrh2 and gnrh3 transcripts were detected during brood pouch growth. Results indicated that brain gnrh2 transcripts remarkably increased at the middle-stage and late-stage of brood pouch growth, while brain gnrh3 transcripts significantly raised at the early-stage and middle-stage. These suggested that GnRH2 and GnRH3 regulated brood pouch growth at different stages. Short-term BaP exposure in lined seahorse was performed. Transcripts of gnrh2 and gnrh3 remarkably increased in females and males exposed to BaP. Besides, plasma 17-beta estradiol (E2) levels presented a reduced trend during female fish exposed to BaP. This revealed that BaP functioned as anti-estrogenic effects and it may result in high expression of gnrh mRNA. However, plasma 11-ketone testosterone (11-KT) levels showed an increased trend during male fish exposed to BaP. Taken together, these indicated interesting results of BaP on reproduction in each sex of seahorse. These observations contribute to provide novel information of regulation on brood pouch growth and effects of BaP on reproductive endocrine in Syngnathidaes.
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Affiliation(s)
- Wenqiang Wang
- School of Agriculture, Ludong University, Yantai 264025, China
| | - Jun Chen
- School of Agriculture, Ludong University, Yantai 264025, China.
| | - Yan Fang
- School of Agriculture, Ludong University, Yantai 264025, China
| | - Bin Wang
- Key Laboratory of Sustainable Development of Marine Fisheries, Ministry of Agriculture and Rural Affairs, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China
| | - Qiang Zou
- Yantai Branch of Shandong Technology Transfer Center, Chinese Academy of Sciences, Yantai 264003, China
| | - Lei Wang
- College of life sciences, Ludong University, Yantai 264025, China
| | - Wenwen Zhang
- School of Agriculture, Ludong University, Yantai 264025, China
| | - Xueying Huang
- School of Agriculture, Ludong University, Yantai 264025, China
| | - Haoyue Lv
- School of Agriculture, Ludong University, Yantai 264025, China
| | - Chenxiao Zhang
- School of Agriculture, Ludong University, Yantai 264025, China
| | - Kai Wang
- School of Agriculture, Ludong University, Yantai 264025, China.
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Chaube R, Rawat A, Sharma S, Senthilkumaran B, Bhat SG, Joy KP. Molecular cloning and characterization of a gonadotropin-releasing hormone 2 precursor cDNA in the catfish Heteropneustes fossilis: Expression profile and regulation by ovarian steroids. Gen Comp Endocrinol 2019; 280:134-146. [PMID: 31015009 DOI: 10.1016/j.ygcen.2019.04.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 04/10/2019] [Accepted: 04/16/2019] [Indexed: 01/26/2023]
Abstract
Gonadotropin-releasing hormone 2 (Gnrh2) is one of the three classes of Gnrh distributed in vertebrates and is highly conserved. In the present study, the cDNA encoding Gnrh2 was isolated and characterized in the ostariophysan catfish Heteropneustes fossilis (hf). The cDNA is 611 bp long with an open reading frame (ORF) of 261 bp that encodes a highly conserved protein of 86 amino acids. The deduced Gnrh2 precursor protein clustered with the vertebrate Gnrh2 type. The sequence identity of hfgnrh2 is 94% with African catfish (Clarias gariepinus) gnrh2 mRNA (accession no. X78047). The hfgnrh2 transcripts were expressed only in the brain and gonads with a higher expression in the female brain and ovary in both resting and prespawning phases. The expression was higher in the prespawning phase than the resting phase. The gnrh2 expression in the brain and ovary showed significant seasonal variations but with opposite patterns. In the brain, the expression was the highest in the preparatory phase, decreased progressively to low levels in the postspawning and resting phases. In the ovary, the transcript level was low in the resting and preparatory phases, increased sharply in the prespawning phase reaching the peak level in the spawning phase and declined sharply in the postspawning phase. The gnrh2 mRNA showed the highest expression in the hind brain-medulla oblongata and moderate to low expression in forebrain regions and pituitary. Ovariectomy resulted in a duration-dependent inhibition of hfgnrh2 mRNA levels in the resting and prespawning phases. Steroid (E2, testosterone and progesterone) replacement treatments (0.5 μg/g body weight) in the 3- week ovariectomized fish restored the inhibition due to ovariectomy, elevated the expression over and above the sham level in the resting phase (E2 group), and raised the levels almost to that of the sham group (testosterone and progesterone groups) in the prespawning phase. In the sham control groups, the steroid replacement resulted in a significant reduction in the mRNA levels. The expression of the gnrh2 mRNA in the brain-pituitary-gonadal axis and its regulation by gonadal steroids suggest that Gnrh2 may have a reproductive role in the catfish.
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Affiliation(s)
- R Chaube
- Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi 221005, India
| | - A Rawat
- Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi 221005, India
| | - S Sharma
- Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi 221005, India
| | - B Senthilkumaran
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Telangana, Hyderabad 500046, India
| | - S G Bhat
- Department of Biotechnology, Cochin University of Science and Technology, Kochi 682022, India
| | - K P Joy
- Department of Biotechnology, Cochin University of Science and Technology, Kochi 682022, India.
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Umatani C, Oka Y. Multiple functions of non-hypophysiotropic gonadotropin releasing hormone neurons in vertebrates. ZOOLOGICAL LETTERS 2019; 5:23. [PMID: 31367467 PMCID: PMC6647275 DOI: 10.1186/s40851-019-0138-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Accepted: 06/19/2019] [Indexed: 06/10/2023]
Abstract
Gonadotropin releasing hormone (GnRH) is a hypophysiotropic hormone that is generally thought to be important for reproduction. This hormone is produced by hypothalamic GnRH neurons and stimulates the secretion of gonadotropins. On the other hand, vertebrates also have non-hypophysiotropic GnRH peptides, which are produced by extrahypothalamic GnRH neurons. They are mainly located in the terminal nerve, midbrain tegmentum, trigeminal nerve, and spinal cord (sympathetic preganglionic nerves). In vertebrates, there are typically three gnrh paralogues (gnrh1, gnrh2, gnrh3). GnRH-expression in the non-hypophysiotropic neurons (gnrh1 or gnrh3 in the terminal nerve and the trigeminal nerve, gnrh2 in the midbrain tegmentum) occurs from the early developmental stages. Recent studies have suggested that non-hypophysiotropic GnRH neurons play various functional roles. Here, we summarize their anatomical/physiological properties and discuss their possible functions, focusing on studies in vertebrates. GnRH neurons in the terminal nerve show different spontaneous firing properties during the developmental stages. These neurons in adulthood show regular pacemaker firing, and it has been suggested that these neurons show neuromodulatory function related to the regulation of behavioral motivation, etc. In addition to their recognized role in neuromodulation in adult, in juvenile fish, these neurons, which show more frequent burst firing than in adults, are suggested to have novel functions. GnRH neurons in the midbrain tegmentum show regular pacemaker firing similar to that of the adult terminal nerve and are suggested to be involved in modulations of feeding (teleosts) or nutrition-related sexual behaviors (musk shrew). GnRH neurons in the trigeminal nerve are suggested to be involved in nociception and chemosensory avoidance, although the literature on their electrophysiological properties is limited. Sympathetic preganglionic cells in the spinal cord were first reported as peptidergic modulatory neurons releasing GnRH with a putative function in coordinating interaction between vasomotor and exocrine outflow in the sympathetic nervous system. The functional role of non-hypophysiotropic GnRH neurons may thus be in the global modulation of neural circuits in a manner dependent on internal conditions or the external environment.
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Affiliation(s)
- Chie Umatani
- Department of Biological Sciences, Graduate School of Science, the University of Tokyo, Tokyo, 113-0033 Japan
| | - Yoshitaka Oka
- Department of Biological Sciences, Graduate School of Science, the University of Tokyo, Tokyo, 113-0033 Japan
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Koide T, Yabuki Y, Yoshihara Y. Terminal Nerve GnRH3 Neurons Mediate Slow Avoidance of Carbon Dioxide in Larval Zebrafish. Cell Rep 2019; 22:1115-1123. [PMID: 29386100 DOI: 10.1016/j.celrep.2018.01.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2017] [Revised: 12/01/2017] [Accepted: 01/05/2018] [Indexed: 12/13/2022] Open
Abstract
Escape responses to threatening stimuli are vital for survival in all animal species. Larval zebrafish display fast escape responses when exposed to tactile, acoustic, and visual stimuli. However, their behavioral responses to chemosensory stimuli remain unknown. In this study, we found that carbon dioxide (CO2) induced a slow avoidance response, which was distinct from the touch-evoked fast escape response. We identified the gonadotropin-releasing hormone 3-expressing terminal nerve as the CO2 sensor in the nose. Wide-field calcium imaging revealed downstream CO2-activated ensembles of neurons along three distinct neural pathways, olfactory, trigeminal, and habenulo-interpeduncular, further reaching the reticulospinal neurons in the hindbrain. Ablation of the nose, terminal nerve, or trigeminal ganglion resulted in a dramatic decrease in CO2-evoked avoidance responses. These findings demonstrate that the terminal nerve-trigeminal system plays a pivotal role in triggering a slow chemosensory avoidance behavior in the larval zebrafish.
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Affiliation(s)
- Tetsuya Koide
- Laboratory for Neurobiology of Synapse, RIKEN Brain Science Institute, Saitama 351-0198, Japan.
| | - Yoichi Yabuki
- Laboratory for Neurobiology of Synapse, RIKEN Brain Science Institute, Saitama 351-0198, Japan
| | - Yoshihiro Yoshihara
- Laboratory for Neurobiology of Synapse, RIKEN Brain Science Institute, Saitama 351-0198, Japan; RIKEN BSI-KAO Collaboration Center, RIKEN Brain Science Institute, Saitama 351-0198, Japan; ERATO Touhara Chemosensory Signal Project, JST, The University of Tokyo, Tokyo 113-8657, Japan.
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Weiler K, Ramakrishnan S. Bisphenol F causes disruption of gonadotropin-releasing hormone neural development in zebrafish via an estrogenic mechanism. Neurotoxicology 2019; 71:31-38. [DOI: 10.1016/j.neuro.2018.12.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 11/26/2018] [Accepted: 12/01/2018] [Indexed: 01/08/2023]
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Honji RM, Caneppele D, Pandolfi M, Lo Nostro FL, Moreira RG. Characterization of the gonadotropin-releasing hormone system in the Neotropical teleost, Steindachneridion parahybae during the annual reproductive cycle in captivity. Gen Comp Endocrinol 2019; 273:73-85. [PMID: 29775567 DOI: 10.1016/j.ygcen.2018.05.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 04/21/2018] [Accepted: 05/06/2018] [Indexed: 02/05/2023]
Abstract
This study evaluated by immunohistochemical and Western blot methods, the distribution of two distinct gonadotropin-releasing hormones (GnRHs), corresponding to catfish GnRH (cfGnRH or GnRH1) and chicken-II GnRH (cGnRH-II or GnRH2), in Steindachneridion parahybae females in captivity, focusing these analyses on the reproductive cycle by semi-quantification of optical density (OD). Further, we found that the GnRH neuronal systems co-localized with their respective GnRH-associated peptides (GAPs). A group of neurons immunoreactive (ir) to GnRH1 were identified along the ventral region of the olfactory bulb (vOB) in the telencephalon (vTel) and in the main areas of the diencephalon (especially the medial basal hypothalamus, HBM), including fibers extending into the pituitary gland. In contrast, GnRH2 neurons were confined to the midbrain tegmentum, close to the ventricular surface, without projections to the pituitary gland. Moreover, a cfGAP (GnRH1)-specific band (9 kDa) was identified in the brain and pituitary gland, while a cGAP-II (GnRH2)-specific band (26 kDa) was observed only in the brain extract. During the reproductive cycle, GnRH1-ir presented greater OD values at the vitellogenic and regression stages than at the previtellogenic stage and after artificially induced to spawn. Larger GnRH2-ir neurons were observed during the reproductive cycle, but a higher OD was identified only in the regression stage compared with the other maturation stages. Finally, GnRH1 axons were found to be directed towards the pituitary, and this GnRH type, which is probably the hypophysiotropic form, can contribute to the reproductive dysfunction that occurs in S. parahybae females in captivity, whereas GnRH2 may act as a neuromodulator and/or neurotransmitter.
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Affiliation(s)
- Renato Massaaki Honji
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, Travessa 14, 321, 05508-090 São Paulo, SP, Brazil; Centro de Aquicultura, Universidade Estadual Paulista (UNESP), Campus de Jaboticabal, Via de Acesso Prof. Paulo Donato Castellane, S/N, 14884-900, Jaboticabal, São Paulo, Brazil.
| | - Danilo Caneppele
- Companhia Energética de São Paulo (CESP), Unidade de Hidrobiologia e Aquicultura, Rodovia dos Tamoios, km 38. 12260-000, Brazil
| | - Matias Pandolfi
- Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires & IBBEA, CONICET-UBA, Ciudad Universitaria (C1428EHA), Buenos Aires, Argentina
| | - Fabiana Laura Lo Nostro
- Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires & IBBEA, CONICET-UBA, Ciudad Universitaria (C1428EHA), Buenos Aires, Argentina
| | - Renata Guimarães Moreira
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, Travessa 14, 321, 05508-090 São Paulo, SP, Brazil
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21
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Choi D. Evolutionary Viewpoint on GnRH (gonadotropin-releasing hormone) in Chordata - Amino Acid and Nucleic Acid Sequences. Dev Reprod 2018; 22:119-132. [PMID: 30023462 PMCID: PMC6048306 DOI: 10.12717/dr.2018.22.2.119] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 04/30/2018] [Accepted: 05/25/2018] [Indexed: 01/18/2023]
Abstract
GnRH (gonadotropin-releasing hormone) is a supreme hormone regulating reproductive activity in most animals. The sequences of amino acid and nucleic acid of GnRH reported up to now are examined from the evolutionary framework of Chordata. All identified GnRH are classified into GnRH1, GnRH2, or GnRH3. In all three forms of GnRH both N-terminal and C-terminal are conserved, which allows for effective binding to their receptors. The three amino acids in the middle of GnRH1 sequence have altered diversely from the primitive Chordata, which is indicative of the adaptation process to the ambient environment. GnRH2 and GnRH3 sequences are well conserved. There are more diverse modifications in the nucleic acids than in amino acid sequence of GnRH1. These variations can result from meiosis, mutation, or epigenetics and indicate that GnRH is the product of natural selection.
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Affiliation(s)
- Donchan Choi
- Dept. of Life Science, College of
Environmental Sciences, Yong-In University, Yongin
17092, Korea
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Umatani C, Oka Y. Juvenile-Specific Burst Firing of Terminal Nerve GnRH3 Neurons Suggests Novel Functions in Addition to Neuromodulation. Endocrinology 2018; 159:1678-1689. [PMID: 29409015 DOI: 10.1210/en.2017-03210] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 01/27/2018] [Indexed: 11/19/2022]
Abstract
Peptidergic neurons are suggested to play a key role in neuromodulation of animal behaviors in response to sensory cues in the environment. Terminal nerve gonadotropin-releasing hormone 3 (TN-GnRH3) neurons are thought to be one of the peptidergic neurons important for such neuromodulation in adult vertebrates. On the other hand, it has been reported that TN-GnRH3 neurons are labeled by a specific GnRH3 antibody from early developmental stages to adulthood and are thus suggested to produce mature GnRH3 peptide even in the early developmental stages. However, it remains unknown when TN-GnRH3 neurons show spontaneous burst firing, which is suggested to be involved in neuropeptide release. Using a whole-brain in vitro preparation of gnrh3:enhanced green fluorescent protein (EGFP) medaka fish, we first recorded spontaneous firings of TN-GnRH3 neurons after hatching to adulthood. Contrary to what one would expect from their neuromodulatory functions-that TN-GnRH3 neurons are more active in adulthood-TN-GnRH3 neurons in juveniles showed spontaneous burst firing more frequently than in adulthood (juvenile-specific burst firing). Ca2+ imaging of TN-GnRH3 neurons in juveniles may further suggest that juvenile-specific burst firing triggers neuropeptide release. Furthermore, juvenile-specific burst firing was suggested to be induced by blocking persistent GABAergic inhibition to the glutamatergic neurons, which leads to an increase in glutamatergic synaptic inputs to TN-GnRH3 neurons. The present study reports that peptidergic neurons show juvenile-specific burst firing involved in triggering peptide release and suggests that juvenile TN-GnRH3 neurons have novel functions, in addition to neuromodulation.
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Affiliation(s)
- Chie Umatani
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Yoshitaka Oka
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
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Chang JP, Pemberton JG. Comparative aspects of GnRH-Stimulated signal transduction in the vertebrate pituitary - Contributions from teleost model systems. Mol Cell Endocrinol 2018; 463:142-167. [PMID: 28587765 DOI: 10.1016/j.mce.2017.06.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 05/31/2017] [Accepted: 06/01/2017] [Indexed: 02/07/2023]
Abstract
Gonadotropin-releasing hormone (GnRH) is a major regulator of reproduction through actions on pituitary gonadotropin release and synthesis. Although it is often thought that pituitary cells are exposed to only one GnRH, multiple GnRH forms are delivered to the pituitary of teleost fishes; interestingly this can include the cGnRH-II form usually thought to be non-hypophysiotropic. GnRHs can regulate other pituitary cell-types, both directly as well as indirectly, and multiple GnRH receptors (GnRHRs) may also be expressed in the pituitary, and even within a single pituitary cell-type. Literature on the differential actions of native GnRH isoforms in primary pituitary cells is largely derived from teleost fishes. This review will outline the diversity and complexity of GnRH-GnRHR signal transduction found within vertebrate gonadotropes as well as extra-gonadotropic sites with special emphasis on comparative studies from fish models. The implications that GnRHR transduction mechanisms are GnRH isoform-, function-, and cell-specific are also discussed.
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Affiliation(s)
- John P Chang
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
| | - Joshua G Pemberton
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
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24
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Kagawa N, Hirose S, Fujimoto K, Nomura C, Fujita Y, Honda A, Komori M. Social rank-dependent expression of gonadotropin-releasing hormones and kisspeptin in the medaka brain. Gen Comp Endocrinol 2017; 249:48-54. [PMID: 28279673 DOI: 10.1016/j.ygcen.2017.03.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 12/09/2016] [Accepted: 03/03/2017] [Indexed: 12/22/2022]
Abstract
Social interactions regulate the expression of several neuropeptides that have a central role in the reproductive system of mammals. Nonmammalian vertebrates also have these neuropeptides or paralogs, however, studies on the social regulation of reproductive physiology in nonmammalian species are limited. In this study, we examined whether the expression of gonadotropin-releasing hormones (GnRHs) and kisspeptin (Kiss1) is affected by social hierarchy resulting from the outcomes of male-male competition in medaka fish (Oryzias latipes). Four males were introduced to each other in an experimental tank, and classified as the most aggressive dominant or the most submissive subordinate fish, based on the frequency of their aggressive acts during a short-term competition. Dominant and subordinate males maintained their social rank during a long-term competition. Immediately after short-term competition, gonadotropin-releasing hormone-3 (GnRH3) level in the olfactory bulb was significantly higher in subordinate males than in dominant males. After long-term competition, dominant males had high level of gonadotropin-releasing hormone-1 (GnRH1) in the preoptic area, whereas subordinate males had lower Kiss1 level in the nucleus ventral tuberis. On the other hand, the levels of gonadotropin-releasing hormone-2 (GnRH2) in the nucleus lateralis valvulae and Kiss1 in the nucleus posterioris periventricularis, and plasma 11-ketotestosterone (11-KT) concentration did not differ between subordinate and dominant males after the short- and long-term competitions. These results suggest that social hierarchy regulates the expression of GnRH1, GnRH3, and Kiss1 without affecting 11-KT level in male medaka.
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Affiliation(s)
- Nao Kagawa
- Department of Life Science, Faculty of Science and Technology, Kindai University, Higashiosaka, Osaka 577-8502, Japan.
| | - Sayuri Hirose
- Department of Life Science, Faculty of Science and Technology, Kindai University, Higashiosaka, Osaka 577-8502, Japan
| | - Keiko Fujimoto
- Department of Life Science, Faculty of Science and Technology, Kindai University, Higashiosaka, Osaka 577-8502, Japan
| | - Chihomi Nomura
- Department of Life Science, Faculty of Science and Technology, Kindai University, Higashiosaka, Osaka 577-8502, Japan
| | - Yuuma Fujita
- Department of Life Science, Faculty of Science and Technology, Kindai University, Higashiosaka, Osaka 577-8502, Japan
| | - Akira Honda
- Department of Life Science, Faculty of Science and Technology, Kindai University, Higashiosaka, Osaka 577-8502, Japan
| | - Mai Komori
- Department of Life Science, Faculty of Science and Technology, Kindai University, Higashiosaka, Osaka 577-8502, Japan
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25
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Okuyama T, Yokoi S, Takeuchi H. Molecular basis of social competence in medaka fish. Dev Growth Differ 2017; 59:211-218. [DOI: 10.1111/dgd.12359] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 04/06/2017] [Accepted: 04/07/2017] [Indexed: 11/30/2022]
Affiliation(s)
- Teruhiro Okuyama
- RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory; Department of Biology and Department of Brain and Cognitive Sciences; Massachusetts Institute of Technology (MIT); Cambridge MA 02139 USA
| | - Saori Yokoi
- Laboratory of Bioresources; National Institute for Basic Biology; Nishigonaka 38 Myodaiji Okazaki 444-8585 Aichi Japan
| | - Hideaki Takeuchi
- Graduate School of Natural Science and Technology; Okayama University; Tsushimanaka 3-1-1 Kita-ku Okayama-shi Okayama 700-8530 Japan
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26
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Liu Y, Tang H, Xie R, Li S, Liu X, Lin H, Zhang Y, Cheng CHK. Genetic Evidence for Multifactorial Control of the Reproductive Axis in Zebrafish. Endocrinology 2017; 158:604-611. [PMID: 28359084 DOI: 10.1210/en.2016-1540] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 12/27/2016] [Indexed: 11/19/2022]
Abstract
It is generally believed that kisspeptin and gonadotropin-releasing hormone (GnRH) are required for reproduction in vertebrates. In this study, we generated gnrh3-null zebrafish and found that gnrh3 mutation did not impair gonad development and reproductive capacity. Moreover, zebrafish triple knockout mutant lacking gnrh3 and the 2 kiss1s genes undergo normal puberty and gonad maturation. The expression of follicle-stimulating hormone beta (fshβ) and luteinizing hormone beta (lhβ) was not significantly altered whereas the expression of neuropeptide Y (npy), tachykinin 3 (tac3), and secretogranin-II (sgII) was significantly increased in the triple knockout mutant, suggesting that compensation mechanisms exist to stimulate the reproductive axis in the absence of kiss and gnrh. Our results challenge the prevailing view that GnRH is indispensable for reproduction across species. These data provide genetic evidence that different mechanisms have evolved for the neuroendocrine control of reproduction between mammals and fish: pulsatile release of GnRH to the portal system is the final gateway to stimulate the reproductive axis in mammals, whereas multiple factors act in parallel with GnRH to stimulate the reproductive axis in certain fish species.
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Affiliation(s)
- Yun Liu
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, and the Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, China
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Haipei Tang
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, and the Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Rui Xie
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, and the Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, China
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Shuisheng Li
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, and the Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Xiaochun Liu
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, and the Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Haoran Lin
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, and the Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Yong Zhang
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, and the Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Christopher H K Cheng
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
- School of Biomedical Sciences Core Laboratory, The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, China
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27
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Liu Y, Lin H. Genetic analysis of the reproductive axis in fish using genome-editing nucleases. Sci Bull (Beijing) 2017; 62:302-308. [PMID: 36659358 DOI: 10.1016/j.scib.2017.01.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2016] [Revised: 10/24/2016] [Accepted: 11/06/2016] [Indexed: 01/21/2023]
Abstract
Reproduction in fish is controlled by the brain-pituitary-gonad reproductive axis. Although genes of the reproductive axis are conserved from fish to humans, their in vivo functions are less clear in fish. Mutant lines of the reproductive axis have been systematically investigated in zebrafish and medaka using recently developed genome-editing nucleases. Here, we review recent progress in the genetic analysis of the reproductive axis in fish as well as the opportunities and challenges of applying genome-editing nucleases in fisheries.
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Affiliation(s)
- Yun Liu
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, and the Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China.
| | - Haoran Lin
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, and the Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China.
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28
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Inagaki T, Smith NL, Sherva KM, Ramakrishnan S. Cross-generational effects of parental low dose BPA exposure on the Gonadotropin-Releasing Hormone3 system and larval behavior in medaka (Oryzias latipes). Neurotoxicology 2016; 57:163-173. [PMID: 27713093 DOI: 10.1016/j.neuro.2016.09.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 09/02/2016] [Accepted: 09/29/2016] [Indexed: 11/18/2022]
Abstract
Growing evidence indicates that chronic exposure to Bisphenol A (BPA) may disrupt normal brain function and behavior mediated by gonadotropin-releasing hormone (GnRH) pathways. Previous studies have shown that low dose BPA (200ng/ml) exposure during embryogenesis altered development of extra-hypothalamic GnRH3 systems and non-reproductive locomotor behavior in medaka. Effects of parental low-dose BPA exposure on the development of GnRH3 systems and locomotor behavior of offspring are not well known. This study examines whether the neurophysiological and behavioral effects of BPA in parents (F0 generation) are carried over to their offspring (F1 generation) using stable transgenic medaka embryos/larvae with GnRH3 neurons tagged with green fluorescent protein (GFP). Parental fish were exposed to BPA (200ng/ml) for either life-long or different developmental time windows. Fertilized F1 eggs were collected and raised in egg/fish water with no environmental exposure to BPA. All experiments were performed on F1 embryos/larvae, which were grouped based on the following parental (F0) BPA exposure conditions - (i) Group 1 (G1): through life; (ii) G2: during embryogenesis and early larval development [1-14days post fertilization (dpf)]; (iii) G3: during neurogenesis (1-5dpf); and (iv) G4: during sex differentiation (5-14dpf). Embryos from unexposed vehicle treated parents served as controls (G0). G1 embryos showed significantly reduced survival rates and delayed hatching time compared to other groups, while G4 embryos hatched significantly earlier than all other groups. At 3 dpf, the GnRH3-GFP intensity was increased by 47% in G3 embryos and decreased in G4 embryos by 59% compared to controls. At 4dpf, G1 fish showed 42% increased intensity, while GFP intensity was reduced by 44% in G3 subjects. In addition, the mean brain size of G1, G3 and G4 embryos were smaller than that of control at 4dpf. At 20dpf, all larvae from BPA-treated parents showed significantly decreased total movement (distance covered) compared with controls, with G2 and G3 fish showing reduced velocity of movement. While at 20 dpf no group differences were seen in the soma diameter of GnRH3-GFP neurons, a 34% decrease in SV2 expression, a marker for synaptic transmission, in G1 larvae was observed. These data suggest that parental BPA exposure during critical windows of embryonic development or chronic treatment affects next-generation offspring both in embryonic and larval brain development as well as larval behavior.
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Affiliation(s)
- T Inagaki
- Department of Biology, University of Puget Sound, Tacoma, WA, USA; Neuroscience Program, University of Puget Sound, Tacoma, WA, USA
| | - N L Smith
- Department of Chemistry/Biochemistry, University of Puget Sound, Tacoma, WA 98416, USA
| | - K M Sherva
- Department of Chemistry/Biochemistry, University of Puget Sound, Tacoma, WA 98416, USA
| | - S Ramakrishnan
- Department of Biology, University of Puget Sound, Tacoma, WA, USA; Neuroscience Program, University of Puget Sound, Tacoma, WA, USA.
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29
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Zhao Y, Singh C, Prober DA, Wayne NL. Morphological and Physiological Interactions Between GnRH3 and Hypocretin/Orexin Neuronal Systems in Zebrafish (Danio rerio). Endocrinology 2016; 157:4012-4020. [PMID: 27533887 PMCID: PMC5045510 DOI: 10.1210/en.2016-1381] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 08/11/2016] [Indexed: 01/11/2023]
Abstract
GnRH neurons integrate internal and external cues to control sexual maturation and fertility. Homeostasis of energy balance and food intake correlates strongly with the status of reproduction. Neuropeptides secreted by the hypothalamus involved in modulating energy balance and feeding may play additional roles in the regulation of reproduction. Hypocretin (Hcrt) (also known as orexin) is one such peptide, primarily controlling sleep/wakefulness, food intake, and reward processing. There is a growing body of evidence indicating that Hcrt/orexin (Hcrt) modulates reproduction through interacting with the hypothalamo-pituitary-gonadal axis in mammals. To explore potential morphological and functional interactions between the GnRH and Hcrt neuronal systems, we employed a variety of experimental approaches including confocal imaging, immunohistochemistry, and electrophysiology in transgenic zebrafish, in which fluorescent proteins are genetically expressed in GnRH3 and Hcrt neurons. Our imaging data revealed close apposition and direct connection between GnRH3 and Hcrt neuronal systems in the hypothalamus during larval development through adulthood. Furthermore, the Hcrt receptor (HcrtR) is expressed in GnRH3 neurons. Electrophysiological data revealed a reversible inhibitory effect of Hcrt on GnRH3 neuron electrical activity, which was blocked by the HcrtR antagonist almorexant. In addition, Hcrt had no effect on the electrical activity of GnRH3 neurons in the HcrtR null mutant zebrafish (HcrtR-/-). Our findings demonstrate a close anatomical and functional relationship between Hcrt and GnRH neuronal systems in zebrafish. It is the first demonstration of a link between neuronal circuits controlling sleeping/arousal/feeding and reproduction in zebrafish, an important animal model for investigating the molecular genetics of development.
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Affiliation(s)
- Yali Zhao
- Department of Physiology (Y.Z., N.L.W.), David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90095; and Division of Biology and Biological Engineering (C.S., D.P.), California Institute of Technology, Pasadena, California 91125
| | - Chanpreet Singh
- Department of Physiology (Y.Z., N.L.W.), David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90095; and Division of Biology and Biological Engineering (C.S., D.P.), California Institute of Technology, Pasadena, California 91125
| | - David A Prober
- Department of Physiology (Y.Z., N.L.W.), David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90095; and Division of Biology and Biological Engineering (C.S., D.P.), California Institute of Technology, Pasadena, California 91125
| | - Nancy L Wayne
- Department of Physiology (Y.Z., N.L.W.), David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90095; and Division of Biology and Biological Engineering (C.S., D.P.), California Institute of Technology, Pasadena, California 91125
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30
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Kim TH, Sohn YC. Changes of Sexual Behaviors in Rapamycin-injected Cichlid Fish Astatotilapia burtoni Males. Dev Reprod 2016; 20:267-274. [PMID: 27796008 PMCID: PMC5078152 DOI: 10.12717/dr.2016.20.3.267] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 09/02/2016] [Accepted: 09/22/2016] [Indexed: 01/08/2023]
Abstract
Cichlid fish species exhibit characteristic sexual behaviors according to not only reproductive stages but also social status. In a reproductive season, Astatotilapia burtoni males compete for females and a small number of dominant winners finally obtain the chance of spermiation. In addition to the characteristic behaviors, the dominant males have relatively bigger gonadotropin-releasing hormone 1 (GnRH1) neurons in the preoptic area (POA) of brain compared to those of subordinate males. Although the stimulatory effect of GnRH1 in vertebrate reproduction is well established, little is known about the triggering signal pathway to control GnRH1 neurons and GnRH1-mediated sexual behavior. In the present study, we evaluated the potential effect of TOR inhibitor rapamycin in relation to the cichlid male behaviors and GnRH1 neuron. After 14 h and 26 h of intraventricular injection of rapamycin, behavior patterns of chasing and courtship display did not show significant changes between rapamycin- and DMSO-injected males. Behaviors of spawning site entry increased in rapamycininjected fish at 26 h post-injection than at 14 h post-injection significantly (P<0.05). Meanwhile, there was a tendency that GnRH1 neurons' soma size in the POA shrank by rapamycin injection, whereas the testes did not show notable changes. Taken together, these results suggest the possible role of TOR signal on GnRH1-mediated sexual behavior in cichlid dominant males, although further biological characterization of the TOR signaling pathway will be required to clarify this matter.
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Affiliation(s)
- Tae Ha Kim
- Dept. of Marine Molecular Bioscience, Gangneung-Wonju National University, Gangneung 25457, Korea
| | - Young Chang Sohn
- Dept. of Marine Molecular Bioscience, Gangneung-Wonju National University, Gangneung 25457, Korea
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31
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Inagaki T, Smith N, Lee EK, Ramakrishnan S. Low dose exposure to Bisphenol A alters development of gonadotropin-releasing hormone 3 neurons and larval locomotor behavior in Japanese Medaka. Neurotoxicology 2015; 52:188-97. [PMID: 26687398 DOI: 10.1016/j.neuro.2015.12.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 11/24/2015] [Accepted: 12/04/2015] [Indexed: 11/30/2022]
Abstract
Accumulating evidence indicates that chronic low dose exposure to Bisphenol A (BPA), an endocrine disruptor, may disrupt normal brain development and behavior mediated by the gonadotropin-releasing hormone (GnRH) pathways. While it is known that GnRH neurons in the hypothalamus regulate reproductive physiology and behavior, functional roles of extra-hypothalamic GnRH neurons remain unclear. Furthermore, little is known whether BPA interacts with extra-hypothalamic GnRH3 neural systems in vulnerable developing brains. Here we examined the impact of low dose BPA exposure on the developing GnRH3 neural system, eye and brain growth, and locomotor activity in transgenic medaka embryos and larvae with GnRH3 neurons tagged with GFP. Fertilized eggs were collected daily and embryos/larvae were chronically exposed to 200ng/ml of BPA, starting at 1 day post fertilization (dpf). BPA significantly increased fluorescence intensity of the GnRH3-GFP neural population in the terminal nerve (TN) of the forebrain at 3dpf, but decreased the intensity at 5dpf, compared with controls. BPA advanced eye pigmentation without affecting eye and brain size development, and accelerated times to hatch. Following chronic BPA exposure, 20dpf larvae showed suppression of locomotion, both in distance covered and speed of movement (47% and 43% reduction, respectively). BPA-induced hypoactivity was accompanied by decreased cell body sizes of individual TN-GnRH3 neurons (14% smaller than those of controls), but not of non-GnRH3 neurons. These novel data demonstrate complex neurobehavioral effects of BPA on the development of extra-hypothalamic GnRH3 neurons in teleost fish.
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Affiliation(s)
- T Inagaki
- Department of Biology, Neuroscience program, University of Puget Sound, Tacoma, WA 98416, USA
| | - N Smith
- Department of Chemistry, University of Puget Sound, Tacoma, WA 98416, USA
| | - E K Lee
- Department of Chemistry, University of Puget Sound, Tacoma, WA 98416, USA
| | - S Ramakrishnan
- Department of Biology, Neuroscience program, University of Puget Sound, Tacoma, WA 98416, USA.
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32
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Kikuchi Y, Hosono K, Yamashita J, Kawabata Y, Okubo K. Glucocorticoid receptor exhibits sexually dimorphic expression in the medaka brain. Gen Comp Endocrinol 2015; 223:47-53. [PMID: 26433060 DOI: 10.1016/j.ygcen.2015.09.031] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2015] [Revised: 08/25/2015] [Accepted: 09/29/2015] [Indexed: 11/18/2022]
Abstract
The differential impact of stress on brain functions of males and females has been widely observed in vertebrates. Recent evidence suggests that stress-induced glucocorticoid signaling affects sexual differentiation and sex changes in teleost fish. These facts led us to postulate that there were sex differences in glucocorticoid signaling in the teleost brain that underlie some sex differences in their physiological and behavioral traits. Here we found sexually dimorphic expression of a glucocorticoid receptor gene (gr1) in the brain of medaka fish (Oryzias latipes), with females having greater expression in several preoptic and thalamic nuclei. Further, gr1 exhibits female-biased expression in neurons of the anterior parvocellular preoptic nucleus that produce the neuropeptides vasotocin and gonadotropin-releasing hormone 1 (these neuropeptides have been implicated in the regulation of neuroendocrine and behavioral functions). These findings suggest that glucocorticoids have a greater influence on physiology and behavior mediated by these neuropeptides in females than in males, which may contribute to sex differences in the brain's response to stress.
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Affiliation(s)
- Yukiko Kikuchi
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan
| | - Kohei Hosono
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan
| | - Junpei Yamashita
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan
| | - Yukika Kawabata
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan
| | - Kataaki Okubo
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
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33
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Huang W, Zhang J, Liao Z, Lv Z, Wu H, Zhu A, Wu C. Genomic structure and promoter functional analysis of GnRH3 gene in large yellow croaker (Larimichthys crocea). Gene 2015; 576:458-65. [PMID: 26519998 DOI: 10.1016/j.gene.2015.10.063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2015] [Revised: 10/09/2015] [Accepted: 10/24/2015] [Indexed: 01/30/2023]
Abstract
Gonadotropin-releasing hormone III (GnRH3) is considered to be a key neurohormone in fish reproduction control. In the present study, the cDNA and genomic sequences of GnRH3 were cloned and characterized from large yellow croaker Larimichthys crocea. The cDNA encoded a protein of 99 amino acids with four functional motifs. The full-length genome sequence was composed of 3797 nucleotides, including four exons and three introns. Higher identities of amino acid sequences and conserved exon-intron organizations were found between LcGnRH3 and other GnRH3 genes. In addition, some special features of the sequences were detected in partial species. For example, two specific residues (V and A) were found in the family Sciaenidae, and the unique 75-72 bp type of the open reading frame 2 and 3 existed in the family Cyprinidae. Analysis of the 2576 bp promoter fragment of LcGnRH3 showed a number of transcription factor binding sites, such as AP1, CREB, GATA-1, HSF, FOXA2, and FOXL1. Promoter functional analysis using an EGFP reporter fusion in zebrafish larvae presented positive signals in the brain, including the olfactory region, the terminal nerve ganglion, the telencephalon, and the hypothalamus. The expression pattern was generally consistent with the endogenous GnRH3 GFP-expressing transgenic zebrafish lines, but the details were different. These results indicate that the structure and function of LcGnRH3 are generally similar to the other teleost GnRH3 genes, but there exist some distinctions among them.
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Affiliation(s)
- Wei Huang
- National Engineering Research Center of Marine Facilities Aquaculture, College of Marine Science and Technology, Zhejiang Ocean University, Zhoushan, Zhejiang 316022, PR China
| | - Jianshe Zhang
- National Engineering Research Center of Marine Facilities Aquaculture, College of Marine Science and Technology, Zhejiang Ocean University, Zhoushan, Zhejiang 316022, PR China
| | - Zhi Liao
- National Engineering Research Center of Marine Facilities Aquaculture, College of Marine Science and Technology, Zhejiang Ocean University, Zhoushan, Zhejiang 316022, PR China
| | - Zhenming Lv
- National Engineering Research Center of Marine Facilities Aquaculture, College of Marine Science and Technology, Zhejiang Ocean University, Zhoushan, Zhejiang 316022, PR China
| | - Huifei Wu
- National Engineering Research Center of Marine Facilities Aquaculture, College of Marine Science and Technology, Zhejiang Ocean University, Zhoushan, Zhejiang 316022, PR China
| | - Aiyi Zhu
- National Engineering Research Center of Marine Facilities Aquaculture, College of Marine Science and Technology, Zhejiang Ocean University, Zhoushan, Zhejiang 316022, PR China
| | - Changwen Wu
- National Engineering Research Center of Marine Facilities Aquaculture, College of Marine Science and Technology, Zhejiang Ocean University, Zhoushan, Zhejiang 316022, PR China
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Selvaraj S, Kitano H, Ohga H, Yamaguchi A, Matsuyama M. Expression changes of mRNAs encoding kisspeptins and their receptors and gonadotropin-releasing hormones during early development and gonadal sex differentiation periods in the brain of chub mackerel (Scomber japonicus). Gen Comp Endocrinol 2015; 222:20-32. [PMID: 25304825 DOI: 10.1016/j.ygcen.2014.09.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2013] [Revised: 09/26/2014] [Accepted: 09/30/2014] [Indexed: 01/15/2023]
Abstract
In recent years, brain kisspeptin system has been shown to be involved in diverse reproductive function, including sexual differentiation in vertebrates. Our previous reports demonstrated that the chub mackerel (Scomber japonicus) brain expresses two kisspeptin (kiss1, kiss2), two kisspeptin receptor (kissr1, kissr2) and three gonadotropin-releasing hormone (gnrh1, gnrh2, gnrh3) genes. In the present study, using quantitative real-time PCR (qRT-PCR) assays, we analysed expression changes of these genes during early development (0-30dphs) and gonadal sex differentiation periods (37-60dphs). Absolute expression level of kiss-kissr-gnrh in the whole head was higher between 0 and 15dphs, in comparison to later developmental periods. Histological analyses revealed presence of sexually differentiated males and females with testicular and ovarian features at 37, 45, and 60dphs. In both males and females, kiss2, kissr1, and kissr2 levels were higher at 37dph, in comparison to 45 and 60dphs, with kiss1 showing no significant differences. Levels of all three gnrh mRNAs were higher at 45dph, in comparison to 60dph. Changes in the expression level of kiss-kissr-gnrh mRNAs in different brain regions of sexually differentiated males and females indicated differences in their regional distribution. These results suggest possible involvement of Kiss-KissR-GnRH systems during early development and gonadal sex differentiation in the chub mackerel.
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Affiliation(s)
- Sethu Selvaraj
- Laboratory of Marine Biology, Department of Bioresource Sciences, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan
| | - Hajime Kitano
- Fisheries Research Institute of Karatsu, Department of Joint Research, Faculty of Agriculture, Kyushu University, Saga 847-0132, Japan
| | - Hirofumi Ohga
- Laboratory of Marine Biology, Department of Bioresource Sciences, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan
| | - Akihiko Yamaguchi
- Laboratory of Marine Biology, Department of Bioresource Sciences, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan
| | - Michiya Matsuyama
- Laboratory of Marine Biology, Department of Bioresource Sciences, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan.
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Takahashi A, Islam MS, Abe H, Okubo K, Akazome Y, Kaneko T, Hioki H, Oka Y. Morphological analysis of the early development of telencephalic and diencephalic gonadotropin-releasing hormone neuronal systems in enhanced green fluorescent protein-expressing transgenic medaka lines. J Comp Neurol 2015; 524:896-913. [DOI: 10.1002/cne.23883] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 08/17/2015] [Accepted: 08/17/2015] [Indexed: 01/06/2023]
Affiliation(s)
- Akiko Takahashi
- Department of Biological Science; Graduate School of Science, The University of Tokyo; Bunkyo-ku Tokyo Japan
| | - M. Sadiqul Islam
- Department of Biological Science; Graduate School of Science, The University of Tokyo; Bunkyo-ku Tokyo Japan
| | - Hideki Abe
- Department of Biological Science; Graduate School of Science, The University of Tokyo; Bunkyo-ku Tokyo Japan
| | - Kataaki Okubo
- Department of Aquatic Bioscience; Graduate School of Agricultural and Life Sciences, The University of Tokyo; Bunkyo-ku Tokyo Japan
| | - Yasuhisa Akazome
- Department of Biological Science; Graduate School of Science, The University of Tokyo; Bunkyo-ku Tokyo Japan
| | - Takeshi Kaneko
- Department of Morphological Brain Science; Graduate School of Medicine, Kyoto University; Kyoto Japan
| | - Hiroyuki Hioki
- Department of Morphological Brain Science; Graduate School of Medicine, Kyoto University; Kyoto Japan
| | - Yoshitaka Oka
- Department of Biological Science; Graduate School of Science, The University of Tokyo; Bunkyo-ku Tokyo Japan
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Forni PE, Wray S. GnRH, anosmia and hypogonadotropic hypogonadism--where are we? Front Neuroendocrinol 2015; 36:165-77. [PMID: 25306902 PMCID: PMC4703044 DOI: 10.1016/j.yfrne.2014.09.004] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 09/08/2014] [Accepted: 09/25/2014] [Indexed: 11/19/2022]
Abstract
Gonadotropin releasing hormone (GnRH) neurons originate the nasal placode and migrate into the brain during prenatal development. Once within the brain, these cells become integral components of the hypothalamic-pituitary-gonadal axis, essential for reproductive function. Disruption of this system causes hypogonadotropic hypogonadism (HH). HH associated with anosmia is clinically defined as Kallman syndrome (KS). Recent work examining the developing nasal region has shed new light on cellular composition, cell interactions and molecular cues responsible for the development of this system in different species. This review discusses some developmental aspects, animal models and current advancements in our understanding of pathologies affecting GnRH. In addition we discuss how development of neural crest derivatives such as the glia of the olfactory system and craniofacial structures control GnRH development and reproductive function.
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Affiliation(s)
- Paolo E Forni
- Department of Biological Sciences and the Center for Neuroscience Research, University at Albany, State University of New York, Albany, NY 12222, United States.
| | - Susan Wray
- Cellular and Developmental Neurobiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, United States.
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Ramallo MR, Morandini L, Alonso F, Birba A, Tubert C, Fiszbein A, Pandolfi M. The endocrine regulation of cichlids social and reproductive behavior through the eyes of the chanchita, Cichlasoma dimerus (Percomorpha; Cichlidae). ACTA ACUST UNITED AC 2014; 108:194-202. [PMID: 25159924 DOI: 10.1016/j.jphysparis.2014.08.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Revised: 05/06/2014] [Accepted: 08/13/2014] [Indexed: 01/12/2023]
Abstract
Sociobiology, the study of social behavior, calls for a laboratory model with specific requirements. Among the most obvious is the execution of social interactions that need to be readily observable, quantifiable and analyzable. If, in turn, one focuses on the neuroendocrinological basis of social behavior, restrictions grow even tighter. A good laboratory model should then allow easy access to its neurological and endocrine components and processes. During the last years, we have been studying the physiological foundation of social behavior on what we believe fits all the aforementioned requirements: the so called "chanchita", Cichlasoma dimerus. This Neotropical cichlid fish exhibits biparental care of the eggs and larvae and presents a hierarchical social system, established and sustained through agonistic interactions. The aim of the current article is to review new evidence on chanchita's social and reproductive behavior.
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Affiliation(s)
- Martín Roberto Ramallo
- Laboratorio de Neuroendocrinología y Comportamiento, IBBEA-Conicet, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria (C1428EHA), CABA, Argentina; Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria (C1428EHA), CABA, Argentina
| | - Leonel Morandini
- Laboratorio de Neuroendocrinología y Comportamiento, IBBEA-Conicet, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria (C1428EHA), CABA, Argentina; Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria (C1428EHA), CABA, Argentina
| | - Felipe Alonso
- Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria (C1428EHA), CABA, Argentina
| | - Agustina Birba
- Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria (C1428EHA), CABA, Argentina
| | - Cecilia Tubert
- Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria (C1428EHA), CABA, Argentina
| | - Ana Fiszbein
- Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria (C1428EHA), CABA, Argentina
| | - Matías Pandolfi
- Laboratorio de Neuroendocrinología y Comportamiento, IBBEA-Conicet, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria (C1428EHA), CABA, Argentina; Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria (C1428EHA), CABA, Argentina.
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Shahjahan M, Kitahashi T, Parhar IS. Central pathways integrating metabolism and reproduction in teleosts. Front Endocrinol (Lausanne) 2014; 5:36. [PMID: 24723910 PMCID: PMC3971181 DOI: 10.3389/fendo.2014.00036] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 03/11/2014] [Indexed: 01/08/2023] Open
Abstract
Energy balance plays an important role in the control of reproduction. However, the cellular and molecular mechanisms connecting the two systems are not well understood especially in teleosts. The hypothalamus plays a crucial role in the regulation of both energy balance and reproduction, and contains a number of neuropeptides, including gonadotropin-releasing hormone (GnRH), orexin, neuropeptide-Y, ghrelin, pituitary adenylate cyclase-activating polypeptide, α-melanocyte stimulating hormone, melanin-concentrating hormone, cholecystokinin, 26RFamide, nesfatin, kisspeptin, and gonadotropin-inhibitory hormone. These neuropeptides are involved in the control of energy balance and reproduction either directly or indirectly. On the other hand, synthesis and release of these hypothalamic neuropeptides are regulated by metabolic signals from the gut and the adipose tissue. Furthermore, neurons producing these neuropeptides interact with each other, providing neuronal basis of the link between energy balance and reproduction. This review summarizes the advances made in our understanding of the physiological roles of the hypothalamic neuropeptides in energy balance and reproduction in teleosts, and discusses how they interact with GnRH, kisspeptin, and pituitary gonadotropins to control reproduction in teleosts.
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Affiliation(s)
- Md. Shahjahan
- Brain Research Institute, School of Medicine and Health Sciences, Monash University Malaysia, Petaling Jaya, Malaysia
| | - Takashi Kitahashi
- Brain Research Institute, School of Medicine and Health Sciences, Monash University Malaysia, Petaling Jaya, Malaysia
| | - Ishwar S. Parhar
- Brain Research Institute, School of Medicine and Health Sciences, Monash University Malaysia, Petaling Jaya, Malaysia
- *Correspondence: Ishwar S. Parhar, Brain Research Institute, School of Medicine and Health Sciences, Monash University Malaysia, Petaling Jaya 46150, Malaysia e-mail:
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