1
|
Fodor I, Osugi T, Matsubara S, Shiraishi A, Kawada T, Pirger Z, Satake H. Characterization of corazonin signaling in a molluscan model species, Lymnaea stagnalis. Gen Comp Endocrinol 2024; 357:114594. [PMID: 39047798 DOI: 10.1016/j.ygcen.2024.114594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2024] [Revised: 07/10/2024] [Accepted: 07/20/2024] [Indexed: 07/27/2024]
Abstract
In recent years, new concepts have emerged regarding the nomenclature, functions, and relationships of different peptide families of the gonadotropin-releasing hormone (GnRH) superfamily. One of the main driving forces for this originated from the emerging evidence that neuropeptides previously called molluscan GnRH are multifunctional and should be classified as corazonin (CRZ). However, research articles still appear that use incorrect nomenclature and attribute the same function to molluscan CRZs as vertebrate GnRHs. The aim of the present study was to further support the recent interpretation of the origin and function of the GnRH superfamily. Towards this goal, we report the characterization of CRZ signaling system in the molluscan model species, the great pond snail (Lymnaea stagnalis). We detected a CRZ-receptor-like sequence (Lym-CRZR) by homology-searching in the Lymnaea transcriptomes and the deduced amino acid sequence showed high sequence similarity to GnRH receptors and CRZ receptors. Molecular phylogenetic tree analysis demonstrated that Lym-CRZR is included in the cluster of molluscan CRZRs. Lym-CRZR transiently transfected into HEK293 cells was found to be localized at the plasma membrane, confirming that it functions as a membrane receptor, like other G protein-coupled receptors. The signaling assays revealed that the previously identified Lym-CRZ neuropeptide stimulated intracellular Ca2+ mobilization in a dose-dependent manner, but not cyclic AMP production, in HEK293 cells transfected with Lym-CRZR. Finally, we demonstrated a wide tissue distribution of Lym-CRZR. These results suggest that Lym-CRZ is a multifunctional peptide and provide further insights into the evolution of the GnRH neuropeptide superfamily. The present study also supports the notion that previously termed molluscan "GnRH" should be classified as "CRZ".
Collapse
Affiliation(s)
- István Fodor
- Ecophysiological and Environmental Toxicological Research Group, HUN-REN Balaton Limnological Research Institute, Tihany 8237, Hungary.
| | - Tomohiro Osugi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1 Seikadai, Seika-cho, Soraku-gun, Kyoto 619-0284, Japan
| | - Shin Matsubara
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1 Seikadai, Seika-cho, Soraku-gun, Kyoto 619-0284, Japan
| | - Akira Shiraishi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1 Seikadai, Seika-cho, Soraku-gun, Kyoto 619-0284, Japan
| | - Tsuyoshi Kawada
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1 Seikadai, Seika-cho, Soraku-gun, Kyoto 619-0284, Japan
| | - Zsolt Pirger
- Ecophysiological and Environmental Toxicological Research Group, HUN-REN Balaton Limnological Research Institute, Tihany 8237, Hungary
| | - Honoo Satake
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1 Seikadai, Seika-cho, Soraku-gun, Kyoto 619-0284, Japan
| |
Collapse
|
2
|
Fodor I, Matsubara S, Osugi T, Shiraishi A, Kawada T, Satake H, Pirger Z. Lack of membrane sex steroid receptors for mediating rapid endocrine responses in molluscan nervous systems. Front Endocrinol (Lausanne) 2024; 15:1458422. [PMID: 39188914 PMCID: PMC11345136 DOI: 10.3389/fendo.2024.1458422] [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: 07/02/2024] [Accepted: 07/30/2024] [Indexed: 08/28/2024] Open
Abstract
Despite the lack of endogenous synthesis and relevant nuclear receptors, several papers have been published over the decades claiming that the physiology of mollusks is affected by natural and synthetic sex steroids. With scant evidence for the existence of functional steroid nuclear receptors in mollusks, some scientists have speculated that the effects of steroids might be mediated via membrane receptors (i.e. via non-genomic/non-classical actions) - a mechanism that has been well-characterized in vertebrates. However, no study has yet investigated the ligand-binding ability of such receptor candidates in mollusks. The aim of the present study was to further trace the evolution of the endocrine system by investigating the presence of functional membrane sex steroid receptors in a mollusk, the great pond snail (Lymnaea stagnalis). We detected sequences homologous to the known vertebrate membrane sex steroid receptors in the Lymnaea transcriptome and genome data: G protein-coupled estrogen receptor-1 (GPER1); membrane progestin receptors (mPRs); G protein-coupled receptor family C group 6 member A (GPRC6A); and Zrt- and Irt-like protein 9 (ZIP9). Sequence analyses, including conserved domain analysis, phylogenetics, and transmembrane domain prediction, indicated that the mPR and ZIP9 candidates appeared to be homologs, while the GPER1 and GPRC6A candidates seemed to be non-orthologous receptors. All candidates transiently transfected into HEK293MSR cells were found to be localized at the plasma membrane, confirming that they function as membrane receptors. However, the signaling assays revealed that none of the candidates interacted with the main vertebrate steroid ligands. Our findings strongly suggest that functional membrane sex steroid receptors which would be homologous to the vertebrate ones are not present in Lymnaea. Although further experiments are required on other molluscan model species as well, we propose that both classical and non-classical sex steroid signaling for endocrine responses are specific to chordates, confirming that molluscan and vertebrate endocrine systems are fundamentally different.
Collapse
Affiliation(s)
- István Fodor
- Ecophysiological and Environmental Toxicological Research Group, HUN-REN Balaton Limnological Research Institute, Tihany, Hungary
| | - Shin Matsubara
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Tomohiro Osugi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Akira Shiraishi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Tsuyoshi Kawada
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Honoo Satake
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Zsolt Pirger
- Ecophysiological and Environmental Toxicological Research Group, HUN-REN Balaton Limnological Research Institute, Tihany, Hungary
| |
Collapse
|
3
|
Satake H, Sasakura Y. The neuroendocrine system of Ciona intestinalis Type A, a deuterostome invertebrate and the closest relative of vertebrates. Mol Cell Endocrinol 2024; 582:112122. [PMID: 38109989 DOI: 10.1016/j.mce.2023.112122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 12/05/2023] [Accepted: 12/09/2023] [Indexed: 12/20/2023]
Abstract
Deuterostome invertebrates, including echinoderms, hemichordates, cephalochordates, and urochordates, exhibit common and species-specific morphological, developmental, physiological, and behavioral characteristics that are regulated by neuroendocrine and nervous systems. Over the past 15 years, omics, genetic, and/or physiological studies on deuterostome invertebrates have identified low-molecular-weight transmitters, neuropeptides and their cognate receptors, and have clarified their various biological functions. In particular, there has been increasing interest on the neuroendocrine and nervous systems of Ciona intestinalis Type A, which belongs to the subphylum Urochordata and occupies the critical phylogenetic position as the closest relative of vertebrates. During the developmental stage, gamma-aminobutylic acid, D-serine, and gonadotropin-releasing hormones regulate metamorphosis of Ciona. In adults, the neuropeptidergic mechanisms underlying ovarian follicle growth, oocyte maturation, and ovulation have been elucidated. This review article provides the most recent and fundamental knowledge of the neuroendocrine and nervous systems of Ciona, and their evolutionary aspects.
Collapse
Affiliation(s)
- Honoo Satake
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan.
| | - Yasunori Sasakura
- Shimoda Marine Research Center, University of Tsukuba, Shizuoka, Japan
| |
Collapse
|
4
|
Matsubara S, Iguchi R, Ogasawara M, Nakamura H, Kataoka TR, Shiraishi A, Osugi T, Kawada T, Satake H. A Novel Hemocyte-Derived Peptide and Its Possible Roles in Immune Response of Ciona intestinalis Type A. Int J Mol Sci 2024; 25:1979. [PMID: 38396656 PMCID: PMC10888236 DOI: 10.3390/ijms25041979] [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: 12/19/2023] [Revised: 01/24/2024] [Accepted: 02/05/2024] [Indexed: 02/25/2024] Open
Abstract
A wide variety of bioactive peptides have been identified in the central nervous system and several peripheral tissues in the ascidian Ciona intestinalis type A (Ciona robusta). However, hemocyte endocrine peptides have yet to be explored. Here, we report a novel 14-amino-acid peptide, CiEMa, that is predominant in the granular hemocytes and unilocular refractile granulocytes of Ciona. RNA-seq and qRT-PCR revealed the high CiEma expression in the adult pharynx and stomach. Immunohistochemistry further revealed the highly concentrated CiEMa in the hemolymph of the pharynx and epithelial cells of the stomach, suggesting biological roles in the immune response. Notably, bacterial lipopolysaccharide stimulation of isolated hemocytes for 1-4 h resulted in 1.9- to 2.4-fold increased CiEMa secretion. Furthermore, CiEMa-stimulated pharynx exhibited mRNA upregulation of the growth factor (Fgf3/7/10/22), vanadium binding proteins (CiVanabin1 and CiVanabin3), and forkhead and homeobox transcription factors (Foxl2, Hox3, and Dbx) but not antimicrobial peptides (CrPap-a and CrMam-a) or immune-related genes (Tgfbtun3, Tnfa, and Il17-2). Collectively, these results suggest that CiEMa plays roles in signal transduction involving tissue development or repair in the immune response, rather than in the direct regulation of immune response genes. The present study identified a novel Ciona hemocyte peptide, CiEMa, which paves the way for research on the biological roles of hemocyte peptides in chordates.
Collapse
Affiliation(s)
- Shin Matsubara
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1 Seikadai, Seika-cho, Soraku-gun 619-0284, Kyoto, Japan (H.S.)
| | - Rin Iguchi
- Department of Biology, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku 263-8522, Chiba, Japan
| | - Michio Ogasawara
- Department of Biology, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku 263-8522, Chiba, Japan
| | - Hiroya Nakamura
- Department of Pathology, Iwate Medical University, 2-1-1 Idaidori, Yahaba-cho, Shiwa-gun 028-3695, Iwate, Japan (T.R.K.)
| | - Tatsuki R. Kataoka
- Department of Pathology, Iwate Medical University, 2-1-1 Idaidori, Yahaba-cho, Shiwa-gun 028-3695, Iwate, Japan (T.R.K.)
| | - Akira Shiraishi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1 Seikadai, Seika-cho, Soraku-gun 619-0284, Kyoto, Japan (H.S.)
| | - Tomohiro Osugi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1 Seikadai, Seika-cho, Soraku-gun 619-0284, Kyoto, Japan (H.S.)
| | - Tsuyoshi Kawada
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1 Seikadai, Seika-cho, Soraku-gun 619-0284, Kyoto, Japan (H.S.)
| | - Honoo Satake
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1 Seikadai, Seika-cho, Soraku-gun 619-0284, Kyoto, Japan (H.S.)
| |
Collapse
|
5
|
Satake H, Kawada T, Osugi T, Sakai T, Shiraishi A, Yamamoto T, Matsubara S. Ovarian Follicle Development in Ascidians. Zoolog Sci 2024; 41:60-67. [PMID: 38587518 DOI: 10.2108/zs230054] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Accepted: 07/20/2023] [Indexed: 04/09/2024]
Abstract
Ovarian follicle development is an essential process for continuation of sexually reproductive animals, and is controlled by a wide variety of regulatory factors such as neuropeptides and peptide hormones in the endocrine, neuroendocrine, and nervous systems. Moreover, while some molecular mechanisms underlying follicle development are conserved, others vary among species. Consequently, follicle development processes are closely related to the evolution and diversity of species. Ciona intestinalis type A (Ciona rubusta) is a cosmopolitan species of ascidians, which are the closest relative of vertebrates. However, unlike vertebrates, ascidians are not endowed with the hypothalamus-pituitary-gonadal axis involving pituitary gonadotropins and sexual steroids. Combined with the phylogenetic position of ascidians as the closest relative of vertebrates, such morphological and endocrine features suggest that ascidians possess both common and species-specific regulatory mechanisms in follicle development. To date, several neuropeptides have been shown to participate in the growth of vitellogenic follicles, oocyte maturation of postvitellogenic follicles, and ovulation of fully mature follicles in a developmental stage-specific fashion. Furthermore, recent studies have shed light on the evolutionary processes of follicle development throughout chordates. In this review, we provide an overview of the neuropeptidergic molecular mechanism in the premature follicle growth, oocyte maturation, and ovulation in Ciona, and comparative views of the follicle development processes of mammals and teleosts.
Collapse
Affiliation(s)
- Honoo Satake
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan,
| | - Tsuyoshi Kawada
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Tomohiro Osugi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Tsubasa Sakai
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Akira Shiraishi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Tatsuya Yamamoto
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Shin Matsubara
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| |
Collapse
|
6
|
Beyer J, Song Y, Lillicrap A, Rodríguez-Satizábal S, Chatzigeorgiou M. Ciona spp. and ascidians as bioindicator organisms for evaluating effects of endocrine disrupting chemicals: A discussion paper. MARINE ENVIRONMENTAL RESEARCH 2023; 191:106170. [PMID: 37708617 DOI: 10.1016/j.marenvres.2023.106170] [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: 05/30/2023] [Revised: 08/25/2023] [Accepted: 09/04/2023] [Indexed: 09/16/2023]
Abstract
In context of testing, screening and monitoring of endocrine-disrupting (ED) type of environmental pollutants, tunicates could possibly represent a particularly interesting group of bioindicator organisms. These primitive chordates are already important model organisms within developmental and genomics research due to their central position in evolution and close relationship to vertebrates. The solitary ascidians, such as the genus Ciona spp. (vase tunicates), could possibly be extra feasible as ED bioindicators. They have a free-swimming, tadpole-like larval stage that develops extremely quickly (<20 h under favorable conditions), has a short life cycle (typically 2-3 months), are relatively easy to maintain in laboratory culture, have fully sequenced genomes, and transgenic embryos with 3D course data of the embryo ontogeny are available. In this article, we discuss possible roles of Ciona spp. (and other solitary ascidians) as ecotoxicological bioindicator organisms in general but perhaps especially for effect studies of contaminants with presumed endocrine disrupting modes of action.
Collapse
Affiliation(s)
- Jonny Beyer
- Norwegian Institute for Water Research (NIVA), Økernveien 94, NO-0579, Oslo, Norway.
| | - You Song
- Norwegian Institute for Water Research (NIVA), Økernveien 94, NO-0579, Oslo, Norway
| | - Adam Lillicrap
- Norwegian Institute for Water Research (NIVA), Økernveien 94, NO-0579, Oslo, Norway
| | | | | |
Collapse
|
7
|
Sakai T, Yamamoto T, Watanabe T, Hozumi A, Shiraishi A, Osugi T, Matsubara S, Kawada T, Sasakura Y, Takahashi T, Satake H. Characterization of a novel species-specific 51-amino acid peptide, PEP51, as a caspase-3/7 activator in ovarian follicles of the ascidian, Ciona intestinalis Type A. Front Endocrinol (Lausanne) 2023; 14:1260600. [PMID: 37842312 PMCID: PMC10570924 DOI: 10.3389/fendo.2023.1260600] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 08/16/2023] [Indexed: 10/17/2023] Open
Abstract
Invertebrates lack hypothalamic-pituitary-gonadal axis, and have acquired species-specific regulatory systems for ovarian follicle development. Ascidians are marine invertebrates that are the phylogenetically closest living relatives to vertebrates, and we have thus far substantiated the molecular mechanisms underlying neuropeptidergic follicle development of the cosmopolitan species, Ciona intestinalis Type A. However, no ovarian factor has so far been identified in Ciona. In the present study, we identified a novel Ciona-specific peptide, termed PEP51, in the ovary. Immunohistochemical analysis demonstrated the specific expression of PEP51 in oocyte-associated accessory cells, test cells, of post-vitellogenic (stage III) follicles. Immunoelectron microscopy revealed that PEP51 was localized in the cytosol of test cells in early stage III follicles, which lack secretory granules. These results indicate that PEP51 acts as an intracellular factor within test cells rather than as a secretory peptide. Confocal laser microscopy verified that activation of caspase-3/7, the canonical apoptosis marker, was detected in most PEP51-positive test cells of early stage III. This colocalization of PEP51 and the apoptosis marker was consistent with immunoelectron microscopy observations demonstrating that a few normal (PEP51-negative) test cells reside in the aggregates of PEP51-positive apoptotic test cells of early stage III follicles. Furthermore, transfection of the PEP51 gene into COS-7 cells and HEK293MSR cells resulted in activation of caspase-3/7, providing evidence that PEP51 induces apoptotic signaling. Collectively, these results showed the existence of species-specific ovarian peptide-driven cell metabolism in Ciona follicle development. Consistent with the phylogenetic position of Ciona as the closest sister group of vertebrates, the present study sheds new light on the molecular and functional diversity of the regulatory systems of follicle development in the Chordata.
Collapse
Affiliation(s)
- Tsubasa Sakai
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Tatsuya Yamamoto
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Takehiro Watanabe
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Akiko Hozumi
- Shimoda Marine Research Center, University of Tsukuba, Shizuoka, Japan
| | - Akira Shiraishi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Tomohiro Osugi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Shin Matsubara
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Tsuyoshi Kawada
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Yasunori Sasakura
- Shimoda Marine Research Center, University of Tsukuba, Shizuoka, Japan
| | - Toshio Takahashi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Honoo Satake
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| |
Collapse
|
8
|
Satake H. Kobayashi Award 2021: Neuropeptides, receptors, and follicle development in the ascidian, Ciona intestinalis Type A: New clues to the evolution of chordate neuropeptidergic systems from biological niches. Gen Comp Endocrinol 2023; 337:114262. [PMID: 36925021 DOI: 10.1016/j.ygcen.2023.114262] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Revised: 03/09/2023] [Accepted: 03/11/2023] [Indexed: 03/17/2023]
Abstract
Ciona intestinalis Type A (Ciona robusta) is a cosmopolitan species belonging to the phylum Urochordata, invertebrate chordates that are phylogenetically the most closely related to the vertebrates. Therefore, this species is of interest for investigation of the evolution and comparative physiology of endocrine, neuroendocrine, and nervous systems in chordates. Our group has identified>30 Ciona neuropeptides (80% of all identified ascidian neuropeptides) primarily using peptidomic approaches combined with reference to genome sequences. These neuropeptides are classified into two groups: homologs or prototypes of vertebrate neuropeptides and novel (Ciona-specific) neuropeptides. We have also identified the cognate receptors for these peptides. In particular, we elucidated multiple receptors for Ciona-specific neuropeptides by a combination of a novel machine learning system and experimental validation of the specific interaction of the predicted neuropeptide-receptor pairs, and verified unprecedented phylogenies of receptors for neuropeptides. Moreover, several neuropeptides were found to play major roles in the regulation of ovarian follicle development. Ciona tachykinin facilitates the growth of vitellogenic follicles via up-regulation of the enzymatic activities of proteases. Ciona vasopressin stimulates oocyte maturation and ovulation via up-regulation of maturation-promoting factor- and matrix metalloproteinase-directed collagen degradation, respectively. Ciona cholecystokinin also triggers ovulation via up-regulation of receptor tyrosine kinase signaling and the subsequent activation of matrix metalloproteinase. These studies revealed that the neuropeptidergic system plays major roles in ovarian follicle growth, maturation, and ovulation in Ciona, thus paving the way for investigation of the biological roles for neuropeptides in the endocrine, neuroendocrine, nervous systems of Ciona, and studies of the evolutionary processes of various neuropeptidergic systems in chordates.
Collapse
Affiliation(s)
- Honoo Satake
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan.
| |
Collapse
|
9
|
Satake H, Osugi T, Shiraishi A. Impact of Machine Learning-Associated Research Strategies on the Identification of Peptide-Receptor Interactions in the Post-Omics Era. Neuroendocrinology 2023; 113:251-261. [PMID: 34348315 DOI: 10.1159/000518572] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 07/19/2021] [Indexed: 11/19/2022]
Abstract
BACKGROUNDS Elucidation of peptide-receptor pairs is a prerequisite for many studies in the neuroendocrine, endocrine, and neuroscience fields. Recent omics analyses have provided vast amounts of peptide and G protein-coupled receptor (GPCR) sequence data. GPCRs for homologous peptides are easily characterized based on homology searching, and the relevant peptide-GPCR interactions are also detected by typical signaling assays. In contrast, conventional evaluation or prediction methods, including high-throughput reverse-pharmacological assays and tertiary structure-based computational analyses, are not useful for identifying interactions between novel and omics-derived peptides and GPCRs. SUMMARY Recently, an approach combining machine learning-based prediction of novel peptide-GPCR pairs and experimental validation of the predicted pairs have been shown to breakthrough this bottleneck. A machine learning method, logistic regression for human class A GPCRs and the multiple subsequent signaling assays led to the deorphanization of human class A orphan GPCRs, namely, the identification of 18 peptide-GPCR pairs. Furthermore, using another machine learning algorithm, the support vector machine (SVM), the peptide descriptor-incorporated SVM was originally developed and employed to predict GPCRs for novel peptides characterized from the closest relative of vertebrates, Ciona intestinalis Type A (Ciona robusta). Experimental validation of the predicted pairs eventually led to the identification of 11 novel peptide-GPCR pairs. Of particular interest is that these newly identified GPCRs displayed neither significant sequence similarity nor molecular phylogenetic relatedness to known GPCRs for peptides. KEY MESSAGES These recent studies highlight the usefulness and versatility of machine learning for enabling the efficient, reliable, and systematic identification of novel peptide-GPCR interactions.
Collapse
Affiliation(s)
- Honoo Satake
- Division of Integrative Biomolecular Function, Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Tomohiro Osugi
- Division of Integrative Biomolecular Function, Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Akira Shiraishi
- Division of Integrative Biomolecular Function, Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| |
Collapse
|
10
|
Kawada T, Osugi T, Matsubara S, Sakai T, Shiraishi A, Yamamoto T, Satake H. Omics Studies for the Identification of Ascidian Peptides, Cognate Receptors, and Their Relevant Roles in Ovarian Follicular Development. Front Endocrinol (Lausanne) 2022; 13:858885. [PMID: 35321341 PMCID: PMC8936170 DOI: 10.3389/fendo.2022.858885] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 02/10/2022] [Indexed: 11/16/2022] Open
Abstract
Omics studies contribute to the elucidation of genomes and profiles of gene expression. In the ascidian Ciona intestinalis Type A (Ciona robusta), mass spectrometry (MS)-based peptidomic studies have detected numerous Ciona-specific (nonhomologous) neuropeptides as well as Ciona homologs of typical vertebrate neuropeptides and hypothalamic peptide hormones. Candidates for cognate G protein-coupled receptors (GPCRs) for these peptides have been found in the Ciona transcriptome by two ways. First, Ciona homologous GPCRs of vertebrate counterparts have been detected by sequence homology searches of cognate transcriptomes. Second, the transcriptome-derived GPCR candidates have been used for machine learning-based systematic prediction of interactions not only between Ciona homologous peptides and GPCRs but also between novel Ciona peptides and GPCRs. These data have ultimately led to experimental evidence for various Ciona peptide-GPCR interactions. Comparative transcriptomics between the wildtype and Ciona vasopressin (CiVP) gene-edited Ciona provide clues to the biological functions of CiVP in ovarian follicular development and whole body growth. Furthermore, the transcriptomes of follicles treated with peptides, such as Ciona tachykinin and cionin (a Ciona cholecystokinin homolog), have revealed key regulatory genes for Ciona follicle growth, maturation, and ovulation, eventually leading to the verification of essential and novel molecular mechanisms underlying these biological events. These findings indicate that omics studies, combined with artificial intelligence and single-cell technologies, pave the way for investigating in greater details the nervous, neuroendocrine, and endocrine systems of ascidians and the molecular and functional evolution and diversity of peptidergic regulatory networks throughout chordates.
Collapse
|
11
|
Matsubara S, Osugi T, Shiraishi A, Wada A, Satake H. Comparative analysis of transcriptomic profiles among ascidians, zebrafish, and mice: Insights from tissue-specific gene expression. PLoS One 2021; 16:e0254308. [PMID: 34559810 PMCID: PMC8462739 DOI: 10.1371/journal.pone.0254308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 09/12/2021] [Indexed: 11/18/2022] Open
Abstract
Tissue/organ-specific genes (TSGs) are important not only for understanding organ development and function, but also for investigating the evolutionary lineages of organs in animals. Here, we investigate the TSGs of 9 adult tissues of an ascidian, Ciona intestinalis Type A (Ciona robusta), which lies in the important position of being the sister group of vertebrates. RNA-seq and qRT-PCR identified the Ciona TSGs in each tissue, and BLAST searches identified their homologs in zebrafish and mice. Tissue distributions of the vertebrate homologs were analyzed and clustered using public RNA-seq data for 12 zebrafish and 30 mouse tissues. Among the vertebrate homologs of the Ciona TSGs in the neural complex, 48% and 63% showed high expression in the zebrafish and mouse brain, respectively, suggesting that the central nervous system is evolutionarily conserved in chordates. In contrast, vertebrate homologs of Ciona TSGs in the ovary, pharynx, and intestine were not consistently highly expressed in the corresponding tissues of vertebrates, suggesting that these organs have evolved in Ciona-specific lineages. Intriguingly, more TSG homologs of the Ciona stomach were highly expressed in the vertebrate liver (17-29%) and intestine (22-33%) than in the mouse stomach (5%). Expression profiles for these genes suggest that the biological roles of the Ciona stomach are distinct from those of their vertebrate counterparts. Collectively, Ciona tissues were categorized into 3 groups: i) high similarity to the corresponding vertebrate tissues (neural complex and heart), ii) low similarity to the corresponding vertebrate tissues (ovary, pharynx, and intestine), and iii) low similarity to the corresponding vertebrate tissues, but high similarity to other vertebrate tissues (stomach, endostyle, and siphons). The present study provides transcriptomic catalogs of adult ascidian tissues and significant insights into the evolutionary lineages of the brain, heart, and digestive tract of chordates.
Collapse
Affiliation(s)
- Shin Matsubara
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
- * E-mail:
| | - Tomohiro Osugi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Akira Shiraishi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Azumi Wada
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Honoo Satake
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| |
Collapse
|
12
|
Cionin, a vertebrate cholecystokinin/gastrin homolog, induces ovulation in the ascidian Ciona intestinalis type A. Sci Rep 2021; 11:10911. [PMID: 34035343 PMCID: PMC8149874 DOI: 10.1038/s41598-021-90295-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 05/10/2021] [Indexed: 01/01/2023] Open
Abstract
Cionin is a homolog of vertebrate cholecystokinin/gastrin that has been identified in the ascidian Ciona intestinalis type A. The phylogenetic position of ascidians as the closest living relatives of vertebrates suggests that cionin can provide clues to the evolution of endocrine/neuroendocrine systems throughout chordates. Here, we show the biological role of cionin in the regulation of ovulation. In situ hybridization demonstrated that the mRNA of the cionin receptor, Cior2, was expressed specifically in the inner follicular cells of pre-ovulatory follicles in the Ciona ovary. Cionin was found to significantly stimulate ovulation after 24-h incubation. Transcriptome and subsequent Real-time PCR analyses confirmed that the expression levels of receptor tyrosine kinase (RTK) signaling genes and a matrix metalloproteinase (MMP) gene were significantly elevated in the cionin-treated follicles. Of particular interest is that an RTK inhibitor and MMP inhibitor markedly suppressed the stimulatory effect of cionin on ovulation. Furthermore, inhibition of RTK signaling reduced the MMP gene expression in the cionin-treated follicles. These results provide evidence that cionin induces ovulation by stimulating MMP gene expression via the RTK signaling pathway. This is the first report on the endogenous roles of cionin and the induction of ovulation by cholecystokinin/gastrin family peptides in an organism.
Collapse
|
13
|
Martins RST, Sousa C, Andrade AR, Molés G, Zanuy S, Gómez A, Canário AVM, Pinto PIS. Galanin isoforms by alternative splicing: Structure, expression, and immunohistochemical location in the gonads of European sea bass. Gen Comp Endocrinol 2021; 305:113730. [PMID: 33545062 DOI: 10.1016/j.ygcen.2021.113730] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 01/15/2021] [Accepted: 01/26/2021] [Indexed: 11/21/2022]
Abstract
Galanin (Gal) is a neuropeptide with multiple functions that is widely expressed in the central and peripheral nervous systems of vertebrates. Anatomical and functional evidence suggests a possible role in regulating reproduction in fishes. To test this possibility, we have isolated and characterized two gal alternative transcripts in European sea bass (Dicentrarchus labrax) that encode two prepropeptides, respectively of 29 (gal_MT853221) and 53 (gal_MT853222) amino acids. The two gal transcripts are highly expressed in brain, pituitary and gonads, and appear to be differentially regulated in males and females. In males, gal_MT853222 in the hypothalamus and gal_MT853221 in the pituitary were downregulated with the progression of spermatogenesis (stages I-III). Both transcripts are downregulated in testicles of 1-year (precocious) and 2-year spermiating males compared to immature fish of the same age. Gal peptides and receptors are expressed throughout ovarian development in the hypothalamic-pituitary-gonadal (HPG) axis of females. In the testis, immunoreactive Gal-29 and Gal-53 peptides were detected in blood vessels and Leydig cells during the spermatogenesis stages I-III but Gal immunostaining was barely undetected in more advanced stages. In the ovary, both peptides localized in interstitial cells and blood vessels and in theca cells surrounding the maturing oocytes. The immunolocalization of galanin in Leydig and theca cells suggests a possible role in steroid production regulation. The different pattern of gal expression and Gal localization in the testis and ovary may suggest the possibility that androgens and estrogens may also regulate Gal gene transcription and translation. Altogether, this study showed evidence for the possible involvement of locally produced Gal in gametogenesis and that its production is differentially regulated in male and female gonads.
Collapse
Affiliation(s)
- Rute S T Martins
- Laboratory of Comparative Endocrinology and Integrative Biology, Centre of Marine Sciences (CCMAR), Faro, Portugal
| | - Carmen Sousa
- Laboratory of Comparative Endocrinology and Integrative Biology, Centre of Marine Sciences (CCMAR), Faro, Portugal
| | - André R Andrade
- Laboratory of Comparative Endocrinology and Integrative Biology, Centre of Marine Sciences (CCMAR), Faro, Portugal
| | - Gregorio Molés
- Institute of Aquaculture Torre de la Sal (IATS-CSIC), Castellon, Spain
| | - Silvia Zanuy
- Institute of Aquaculture Torre de la Sal (IATS-CSIC), Castellon, Spain
| | - Ana Gómez
- Institute of Aquaculture Torre de la Sal (IATS-CSIC), Castellon, Spain
| | - Adelino V M Canário
- Laboratory of Comparative Endocrinology and Integrative Biology, Centre of Marine Sciences (CCMAR), Faro, Portugal
| | - Patrícia I S Pinto
- Laboratory of Comparative Endocrinology and Integrative Biology, Centre of Marine Sciences (CCMAR), Faro, Portugal.
| |
Collapse
|
14
|
Yamagaki T, Kimura Y, Yamazaki T. Amidation/non-amidation top-down analysis of endogenous neuropeptide Y in brain tissue by nano flow liquid chromatography orbitrap Fourier transform mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2021; 56:e4716. [PMID: 33759292 PMCID: PMC8047898 DOI: 10.1002/jms.4716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 11/20/2020] [Accepted: 03/02/2021] [Indexed: 05/05/2023]
Abstract
Neuropeptide Y (NPY) is a transmitter molecule in nerve system, and it was an over 4-kDa large peptide with the C-terminal end amidation. NPY is biosynthesized through many maturation processes from a large pre-pro-peptide with peptide-cleavages and amidation that is important to study the biosynthesis regulation. Previously, it was reported that cathepsin L participates in the production of NPY and that cathepsin L generates both of amidated and non-amidated NPYs. However, the non-amidated NPY (NPY-COOH) has not been reported in brain tissues until now. In this study, endogenous NPY-COOH in mouse brain tissue was detected and identified by using nano flow liquid chromatography (nanoLC) orbitrap Fourier transform mass spectrometry (FT-MS) after the effective purification and separation of NPY-COOH from NPY-amide and other peptides using two different gel-filtration chromatography. Amidated NPY was eluted earlier than non-amidated NPY-COOH in the C18 reversed phase nanoLC and the silica-based gel-filtration chromatogram with hydrophobic interaction. The amount of endogenous NPY-COOH was about 0.05% of the matured NPY-amide amount in adult mouse brain.
Collapse
Affiliation(s)
- Tohru Yamagaki
- Suntory Institute for Bioorganic ResearchSuntory Foundation for Life SciencesKyotoJapan
| | - Yuka Kimura
- Suntory Institute for Bioorganic ResearchSuntory Foundation for Life SciencesKyotoJapan
| | - Takashi Yamazaki
- Suntory Institute for Bioorganic ResearchSuntory Foundation for Life SciencesKyotoJapan
| |
Collapse
|
15
|
Al-Alem L, Puttabyatappa M, Shrestha K, Choi Y, Rosewell K, Brännström M, Akin J, Jo M, Duffy DM, Curry TE. Neurotensin: a neuropeptide induced by hCG in the human and rat ovary during the periovulatory period†. Biol Reprod 2021; 104:1337-1346. [PMID: 33682882 PMCID: PMC8485077 DOI: 10.1093/biolre/ioab036] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 02/04/2021] [Accepted: 03/02/2021] [Indexed: 01/06/2023] Open
Abstract
Neurotensin (NTS) is a tridecapeptide that was first characterized as a neurotransmitter in neuronal cells. The present study examined ovarian NTS expression across the periovulatory period in the human and the rat. Women were recruited into this study and monitored by transvaginal ultrasound. The dominant follicle was surgically excised prior to the luteinizing hormone (LH) surge (preovulatory phase) or women were given 250 μg human chorionic gonadotropin (hCG) and dominant follicles collected 12-18 h after hCG (early ovulatory), 18-34 h (late ovulatory), and 44-70 h (postovulatory). NTS mRNA was massively induced during the early and late ovulatory stage in granulosa cells (GCs) (15 000 fold) and theca cells (700 fold). In the rat, hCG also induced Nts mRNA expression in intact ovaries and isolated GCs. In cultured granulosa-luteal cells (GLCs) from IVF patients, NTS expression was induced 6 h after hCG treatment, whereas in cultured rat GCs, NTS increased 4 h after hCG treatment. Cells treated with hCG signaling pathway inhibitors revealed that NTS expression is partially regulated in the human and rat GC by the epidermal-like growth factor pathway. Human GLC, and rat GCs also showed that Nts was regulated by the protein kinase A (PKA) pathway along with input from the phosphotidylinositol 3- kinase (PI3K) and mitogen-activated protein kinase (MAPK) pathways. The predominat NTS receptor present in human and rat GCs was SORT1, whereas NTSR1 and NTSR2 expression was very low. Based on NTS actions in other systems, we speculate that NTS may regulate crucial aspects of ovulation such as vascular permeability, inflammation, and cell migration.
Collapse
Affiliation(s)
- Linah Al-Alem
- Department of Obstetrics and Gynecology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Muraly Puttabyatappa
- Department of Obstetrics and Gynecology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Ketan Shrestha
- Department of Obstetrics and Gynecology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Yohan Choi
- Department of Obstetrics and Gynecology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Kathy Rosewell
- Department of Obstetrics and Gynecology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Mats Brännström
- Department of Obstetrics and Gynecology, Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden,Stockholm IVF, Stockholm, Sweden
| | - James Akin
- Bluegrass Fertility Center, Lexington, KY, USA
| | - Misung Jo
- Department of Obstetrics and Gynecology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Diane M Duffy
- Department of Physiological Sciences, Eastern Virginia Medical School, Norfolk, VA, USA
| | - Thomas E Curry
- Department of Obstetrics and Gynecology, College of Medicine, University of Kentucky, Lexington, KY, USA,Correspondence: Department of Obstetrics and Gynecology, Chandler Medical Center, University of Kentucky, 800 Rose Street,Room MS 331, Lexington, KY 40536-0298, USA. E-mail:
| |
Collapse
|
16
|
Kim K, Gibboney S, Razy-Krajka F, Lowe EK, Wang W, Stolfi A. Regulation of Neurogenesis by FGF Signaling and Neurogenin in the Invertebrate Chordate Ciona. Front Cell Dev Biol 2020; 8:477. [PMID: 32656209 PMCID: PMC7324659 DOI: 10.3389/fcell.2020.00477] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 05/21/2020] [Indexed: 12/22/2022] Open
Abstract
Neurogenesis is a complex sequence of cellular processes and behaviors driven by the coordinated expression of conserved effectors. The bipolar tail neurons (BTNs) of Ciona develop according to a highly dynamic, yet highly stereotyped developmental program and thus could serve as an accessible model system for neurogenesis, including underlying cell behaviors like neuronal delamination, migration, and polarized axon outgrowth. Here we investigate both the upstream events that shape BTN neurogenesis through spatiotemporal regulation of the conserved proneural factor Neurog, spatiotemporal, and the gene expression profile of differentiating BTNs downstream of Neurog activity. We show that, although early FGF signaling is required for Neurog expression and BTN specification, Fgf8/17/18 is expressed in tail tip cells at later stages and suppresses sustained Neurog expression in the anterior BTN (aBTN) lineage, such that only one cell (the one furthest from the source of Fgf8/17/18) maintains Neurog expression and becomes a neuron. Curiously, Fgf8/17/18 might not affect neurogenesis of the posterior BTNs (pBTNs), which are in direct contact with the Fgf8/17/18-expressing cells. Finally, to profile gene expression associated with BTN neurogenesis we performed RNAseq of isolated BTN lineage cells in which BTN neurogenesis was enhanced or suppressed by perturbing Neurog function. This allowed us to identify several candidate genes that might play conserved roles in neurogenesis and neuronal migration in other animals, including mammals.
Collapse
Affiliation(s)
- Kwantae Kim
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, United States
| | - Susanne Gibboney
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, United States
| | - Florian Razy-Krajka
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, United States
| | - Elijah K. Lowe
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, United States
| | - Wei Wang
- Department of Biology, New York University, New York, NY, United States
| | - Alberto Stolfi
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, United States
| |
Collapse
|
17
|
The ventral peptidergic system of the adult ascidian Ciona robusta (Ciona intestinalis Type A) insights from a transgenic animal model. Sci Rep 2020; 10:1892. [PMID: 32024913 PMCID: PMC7002689 DOI: 10.1038/s41598-020-58884-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 01/14/2020] [Indexed: 12/12/2022] Open
Abstract
Ascidians are the sister group of vertebrates and occupy a critical position in explorations of the evolution of the endocrine and nervous systems of chordates. Here, we describe the complete ventral peptidergic system in adult transgenic Ciona robusta (Ciona intestinalis Type A) which expresses the Kaede reporter gene driven by the prohormone convertase 2 (PC2) gene promoter. Numerous PC2 promoter-driven fluorescent (Kaede-positive) non-neural cells were distributed in the blood sinus located at the anterior end of the pharynx, suggesting the acquisition of a peptidergic circulatory system in Ciona. Kaede-positive ciliated columnar cells, rounded cells, and tall ciliated cells were observed in the alimentary organs, including the endostyle, pharynx, esophagus, stomach, and intestine, suggesting that digestive functions are regulated by multiple peptidergic systems. In the heart, Kaede-positive neurons were located in the ring-shaped plexus at both ends of the myocardium. Nerve fiber-like tracts ran along the raphe and appeared to be connected with the plexuses. Such unique structures suggest a role for the peptidergic system in cardiac function. Collectively, the present anatomic analysis revealed the major framework of the ventral peptidergic system of adult Ciona, which could facilitate investigations of peptidergic regulation of the pharynx, endostyle, alimentary tissues, and heart.
Collapse
|
18
|
Nässel DR, Zandawala M, Kawada T, Satake H. Tachykinins: Neuropeptides That Are Ancient, Diverse, Widespread and Functionally Pleiotropic. Front Neurosci 2019; 13:1262. [PMID: 31824255 PMCID: PMC6880623 DOI: 10.3389/fnins.2019.01262] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 11/06/2019] [Indexed: 12/29/2022] Open
Abstract
Tachykinins (TKs) are ancient neuropeptides present throughout the bilaterians and are, with some exceptions, characterized by a conserved FX1GX2Ramide carboxy terminus among protostomes and FXGLMamide in deuterostomes. The best-known TK is the vertebrate substance P, which in mammals, together with other TKs, has been implicated in health and disease with important roles in pain, inflammation, cancer, depressive disorder, immune system, gut function, hematopoiesis, sensory processing, and hormone regulation. The invertebrate TKs are also known to have multiple functions in the central nervous system and intestine and these have been investigated in more detail in the fly Drosophila and some other arthropods. Here, we review the protostome and deuterostome organization and evolution of TK precursors, peptides and their receptors, as well as their functions, which appear to be partly conserved across Bilateria. We also outline the distribution of TKs in the brains of representative organisms. In Drosophila, recent studies have revealed roles of TKs in early olfactory processing, neuromodulation in circuits controlling locomotion and food search, nociception, aggression, metabolic stress, and hormone release. TK signaling also regulates lipid metabolism in the Drosophila intestine. In crustaceans, TK is an important neuromodulator in rhythm-generating motor circuits in the stomatogastric nervous system and a presynaptic modulator of photoreceptor cells. Several additional functional roles of invertebrate TKs can be inferred from their distribution in various brain circuits. In addition, there are a few interesting cases where invertebrate TKs are injected into prey animals as vasodilators from salivary glands or paralyzing agents from venom glands. In these cases, the peptides are produced in the glands of the predator with sequences mimicking the prey TKs. Lastly, the TK-signaling system appears to have duplicated in Panarthropoda (comprising arthropods, onychophores, and tardigrades) to give rise to a novel type of peptides, natalisins, with a distinct receptor. The distribution and functions of natalisins are distinct from the TKs. In general, it appears that TKs are widely distributed and act in circuits at short range as neuromodulators or cotransmitters.
Collapse
Affiliation(s)
- Dick R. Nässel
- Department of Zoology, Stockholm University, Stockholm, Sweden
| | - Meet Zandawala
- Department of Neuroscience, Brown University, Providence, RI, United States
| | - Tsuyoshi Kawada
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Honoo Satake
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| |
Collapse
|
19
|
Matsubara S, Shiraishi A, Osugi T, Kawada T, Satake H. The regulation of oocyte maturation and ovulation in the closest sister group of vertebrates. eLife 2019; 8:49062. [PMID: 31573508 PMCID: PMC6786877 DOI: 10.7554/elife.49062] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 09/26/2019] [Indexed: 01/10/2023] Open
Abstract
Ascidians are the closest living relatives of vertebrates, and their study is important for understanding the evolutionary processes of oocyte maturation and ovulation. In this study, we first examined the ovulation of Ciona intestinalis Type A by monitoring follicle rupture in vitro, identifying a novel mechanism of neuropeptidergic regulation of oocyte maturation and ovulation. Ciona vasopressin family peptide (CiVP) directly upregulated the phosphorylation of extracellular signal-regulated kinase (CiErk1/2) via its receptor. CiVP ultimately activated a maturation-promoting factor, leading to oocyte maturation via germinal vesicle breakdown. CiErk1/2 also induced expression of matrix metalloproteinase (CiMMP2/9/13) in the oocyte, resulting in collagen degradation in the outer follicular cell layer and liberation of fertile oocytes from the ovary. This is the first demonstration of essential pathways regulating oocyte maturation and ovulation in ascidians and will facilitate investigations of the evolutionary process of peptidergic regulation of oocyte maturation and ovulation throughout the phylum Chordata.
Collapse
Affiliation(s)
- Shin Matsubara
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan.,Research Fellow of Japan Society for the Promotion of Science, Tokyo, Japan
| | - Akira Shiraishi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Tomohiro Osugi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Tsuyoshi Kawada
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| | - Honoo Satake
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Kyoto, Japan
| |
Collapse
|
20
|
Satake H, Matsubara S, Shiraishi A, Yamamoto T, Osugi T, Sakai T, Kawada T. Peptide receptors and immune-related proteins expressed in the digestive system of a urochordate, Ciona intestinalis. Cell Tissue Res 2019; 377:293-308. [PMID: 31079207 DOI: 10.1007/s00441-019-03024-8] [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: 12/17/2018] [Accepted: 04/01/2019] [Indexed: 12/17/2022]
Abstract
The digestive system is responsible for nutrient intake and defense against pathogenic microbes. Thus, identification of regulatory factors for digestive functions and immune systems is a key step to the verification of the life cycle, homeostasis, survival strategy and evolutionary aspects of an organism. Over the past decade, there have been increasing reports on neuropeptides, their receptors, variable region-containing chitin-binding proteins (VCBPs) and Toll-like receptors (TLRs) in the ascidian, Ciona intestinalis. Mass spectrometry-based peptidomes and genome database-searching detected not only Ciona orthologs or prototypes of vertebrate peptides and their receptors, including cholecystokinin, gonadotropin-releasing hormones, tachykinin, calcitonin and vasopressin but also Ciona-specific neuropeptides including Ci-LFs and Ci-YFVs. The species-specific regulation of GnRHergic signaling including unique signaling control via heterodimerization among multiple GnRH receptors has also been revealed. These findings shed light on the remarkable significance of ascidians in investigations of the evolution and diversification of the peptidergic systems in chordates. In the defensive systems of C. intestinalis, VCBPs and TLRs have been shown to play major roles in the recognition of exogenous microbes in the innate immune system. These findings indicate both common and species-specific functions of the innate immunity-related molecules between C. intestinalis and vertebrates. In this review article, we present recent advances in molecular and functional features and evolutionary aspects of major neuropeptides, their receptors, VCBPs and TLRs in C. intestinalis.
Collapse
Affiliation(s)
- Honoo Satake
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1 Seikadai, Seika, Souraku, Kyoto, 619-0284, Japan.
| | - Shin Matsubara
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1 Seikadai, Seika, Souraku, Kyoto, 619-0284, Japan
| | - Akira Shiraishi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1 Seikadai, Seika, Souraku, Kyoto, 619-0284, Japan
| | - Tatsuya Yamamoto
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1 Seikadai, Seika, Souraku, Kyoto, 619-0284, Japan
| | - Tomohiro Osugi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1 Seikadai, Seika, Souraku, Kyoto, 619-0284, Japan
| | - Tsubasa Sakai
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1 Seikadai, Seika, Souraku, Kyoto, 619-0284, Japan
| | - Tsuyoshi Kawada
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1 Seikadai, Seika, Souraku, Kyoto, 619-0284, Japan
| |
Collapse
|
21
|
Nakayama S, Sekiguchi T, Ogasawara M. Molecular and evolutionary aspects of the protochordate digestive system. Cell Tissue Res 2019; 377:309-320. [PMID: 31049686 DOI: 10.1007/s00441-019-03035-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 04/12/2019] [Indexed: 02/03/2023]
Abstract
The digestive system is a functional unit consisting of an endodermal tubular structure (alimentary canal) and accessory organs that function in nutrition processing in most triploblastic animals. Various morphologies and apparatuses are formed depending on the phylogenetical relationship and food habits of the specific species. Nutrition processing and morphogenesis of the alimentary canal and accessory organs have both been investigated in vertebrates, mainly humans and mammals. When attempting to understand the evolutionary processes that led to the vertebrate digestive system, however, it is useful to examine other chordates, specifically protochordates, which share fundamental functional and morphogenetic molecules with vertebrates, which also possess non-duplicated genomes. In protochordates, basic anatomical and physiological studies have mainly described the characteristic traits of suspension feeders. Recent progress in genome sequencing has allowed researchers to comprehensively detail protochordate genes and has compared the genetic backgrounds among chordate nutrition processing and alimentary canal/accessory organ systems based on genomic information. Gene expression analyses have revealed spatiotemporal gene expression profiles in protochordate alimentary canals. Additionally, to investigate the basis of morphological diversity in the chordate alimentary canal and accessory organs, evolutionary developmental research has examined developmental transcription factors related to morphogenesis and anterior-posterior pattering of the alimentary canal and accessory organs. In this review, we summarize the current knowledge of molecules involved in nutrition processing and the development of the alimentary canal and accessory organs with innate immune and endocrine roles in protochordates and we explore the molecular basis for understanding the evolution of the chordate digestive system.
Collapse
Affiliation(s)
- Satoshi Nakayama
- The Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba, 263-8522, Japan
| | - Toshio Sekiguchi
- The Noto Marine Laboratory, Division of Marine Environmental Studies, Institute of Nature and Environmental Technology, Kanazawa University, Hosu-gun, Ishikawa, 927-0553, Japan
| | - Michio Ogasawara
- The Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba, 263-8522, Japan.
| |
Collapse
|
22
|
Abstract
Neuropeptides play pivotal roles in various biological events in the nervous, neuroendocrine, and endocrine systems, and are correlated with both physiological functions and unique behavioral traits of animals. Elucidation of functional interaction between neuropeptides and receptors is a crucial step for the verification of their biological roles and evolutionary processes. However, most receptors for novel peptides remain to be identified. Here, we show the identification of multiple G protein-coupled receptors (GPCRs) for species-specific neuropeptides of the vertebrate sister group, Ciona intestinalis Type A, by combining machine learning and experimental validation. We developed an original peptide descriptor-incorporated support vector machine and used it to predict 22 neuropeptide-GPCR pairs. Of note, signaling assays of the predicted pairs identified 1 homologous and 11 Ciona-specific neuropeptide-GPCR pairs for a 41% hit rate: the respective GPCRs for Ci-GALP, Ci-NTLP-2, Ci-LF-1, Ci-LF-2, Ci-LF-5, Ci-LF-6, Ci-LF-7, Ci-LF-8, Ci-YFV-1, and Ci-YFV-3. Interestingly, molecular phylogenetic tree analysis revealed that these receptors, excluding the Ci-GALP receptor, were evolutionarily unrelated to any other known peptide GPCRs, confirming that these GPCRs constitute unprecedented neuropeptide receptor clusters. Altogether, these results verified the neuropeptide-GPCR pairs in the protochordate and evolutionary lineages of neuropeptide GPCRs, and pave the way for investigating the endogenous roles of novel neuropeptides in the closest relatives of vertebrates and the evolutionary processes of neuropeptidergic systems throughout chordates. In addition, the present study also indicates the versatility of the machine-learning-assisted strategy for the identification of novel peptide-receptor pairs in various organisms.
Collapse
|
23
|
Neuropeptides, Peptide Hormones, and Their Receptors of a Tunicate, Ciona intestinalis. Results Probl Cell Differ 2019; 68:107-125. [PMID: 31598854 DOI: 10.1007/978-3-030-23459-1_5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The critical phylogenetic position of the ascidian, Ciona intestinalis, as the closest relative of vertebrates, suggested its potential applicability as a model organism in a wide variety of biological events including the nervous, neuroendocrine, and endocrine regulation. To date, approximately 40 neuropeptides and/or peptide hormones and several cognate receptors have been identified. These peptides are categorized into two types: (1) orthologs of vertebrate peptides, such as cholecystokinin, GnRH, tachykinin, vasopressin, and calcitonin, and (2) novel family peptides such as LF peptides and YFL/V peptides. Ciona GnRH receptors (Ci-GnRHR) were found to be multiplicated in the Ciona-specific lineages and to form unique heterodimers between Ci-GnRHR1 and R4 and between Ci-GnRHR2 and R4, leading to fine-tuning of the generation of second messengers. Furthermore, Ciona tachykinin was shown to regulate a novel protease-associated follicle growth pathway. These findings will pave the way for the exploration of both conserved and diversified endocrine, neuroendocrine, and nervous systems in the evolutionary lineage of invertebrate deuterostomes and/or chordates. In this chapter, we provide an overview of primary sequences, functions, and evolutionary aspects of neuropeptides, peptide hormones, and their receptors in C. intestinalis.
Collapse
|
24
|
Horie T, Horie R, Chen K, Cao C, Nakagawa M, Kusakabe TG, Satoh N, Sasakura Y, Levine M. Regulatory cocktail for dopaminergic neurons in a protovertebrate identified by whole-embryo single-cell transcriptomics. Genes Dev 2018; 32:1297-1302. [PMID: 30228204 PMCID: PMC6169837 DOI: 10.1101/gad.317669.118] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Accepted: 08/02/2018] [Indexed: 01/09/2023]
Abstract
The CNS of the protovertebrate Ciona intestinalis contains a single cluster of dopaminergic (DA) neurons, the coronet cells, which have been likened to the hypothalamus of vertebrates. Whole-embryo single-cell RNA sequencing (RNA-seq) assays identified Ptf1a as the most strongly expressed cell-specific transcription factor (TF) in DA/coronet cells. Knockdown of Ptf1a activity results in their loss, while misexpression results in the appearance of supernumerary DA/coronet cells. Photoreceptor cells and ependymal cells are the most susceptible to transformation, and both cell types express high levels of Meis Coexpression of both Ptf1a and Meis caused the wholesale transformation of the entire CNS into DA/coronet cells. We therefore suggest that the reiterative use of functional manipulations and single-cell RNA-seq assays is an effective means for the identification of regulatory cocktails underlying the specification of specific cell identities.
Collapse
Affiliation(s)
- Takeo Horie
- Shimoda Marine Research Center, University of Tsukuba, Shimoda, Shizuoka 415-0025, Japan
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544, USA
- Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology (PREST), Kawaguchi, Saitama 332-0012, Japan
| | - Ryoko Horie
- Shimoda Marine Research Center, University of Tsukuba, Shimoda, Shizuoka 415-0025, Japan
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544, USA
| | - Kai Chen
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544, USA
| | - Chen Cao
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544, USA
| | - Masashi Nakagawa
- Department of Life Science, Graduate School of Life Science, University of Hyogo, Kamigori, Ako-gun, Hyogo 678-1297, Japan
| | - Takehiro G Kusakabe
- Department of Biology, Faculty of Science and Engineering, Konan University, Kobe, Hyogo 658-8501, Japan
- Institute for Integrative Neurobiology, Konan University, Kobe, Hyogo 658-8501, Japan
| | - Noriyuki Satoh
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa 904-0495, Japan
| | - Yasunori Sasakura
- Shimoda Marine Research Center, University of Tsukuba, Shimoda, Shizuoka 415-0025, Japan
| | - Michael Levine
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544, USA
- Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544, USA
| |
Collapse
|
25
|
Heterodimerization of the prostaglandin E2 receptor EP2 and the calcitonin receptor CTR. PLoS One 2017; 12:e0187711. [PMID: 29095955 PMCID: PMC5667882 DOI: 10.1371/journal.pone.0187711] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 10/24/2017] [Indexed: 12/14/2022] Open
Abstract
G protein-coupled receptors (GPCRs) have been found to form heterodimers and modulate or fine-tune the functions of GPCRs. However, the involvement of GPCR heterodimerization and its functional consequences in gonadal tissues, including granulosa cells, have been poorly investigated, mainly due to the lack of efficient method for identification of novel GPCR heterodimers. In this paper, we identified a novel GPCR heterodimer between prostaglandin E2 (PGE2) receptor 2 (EP2) and calcitonin (CT) receptor (CTR). High-resolution liquid chromatography (LC)-tandem mass spectrometry (MS/MS) of protease-digested EP2-coimmunoprecipitates detected protein fragments of CTR in an ovarian granulosa cell line, OV3121. Western blotting of EP2- and CTR-coimmunoprecipitates detected a specific band for EP2-CTR heterodimer. Specific heterodimerization between EP2 and CTR was also observed by fluorescence resonance energy transfer analysis in HEK293MSR cells expressing cyan- and yellow-fluorescent protein-fused EP2 and CTR, respectively. Collectively, these results provided evidence for heterodimerization between EP2 and CTR. Moreover, Ca2+ mobilization by CT was approximately 40% less potent in HEK293MSR cells expressing an EP2-CTR heterodimer, whereas cAMP production by EP2 or CT was not significantly altered compared with cells expressing EP2- or CTR alone. These functional analyses verified that CTR-mediated Ca2+ mobilization is specifically decreased via heterodimerization with EP2. Altogether, the present study suggests that a novel GPCR heterodimer, EP2-CTR, is involved in some functional regulation, and paves the way for investigation of novel biological roles of CTR and EP2 in various tissues.
Collapse
|
26
|
Kaser-Eichberger A, Trost A, Strohmaier C, Bogner B, Runge C, Bruckner D, Hohberger B, Jünemann A, Kofler B, Reitsamer HA, Schrödl F. Distribution of the neuro-regulatory peptide galanin in the human eye. Neuropeptides 2017; 64:85-93. [PMID: 27914762 DOI: 10.1016/j.npep.2016.11.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 11/22/2016] [Accepted: 11/22/2016] [Indexed: 02/07/2023]
Abstract
Galanin (GAL) is a neuro-regulatory peptide involved in many physiological and pathophysiological processes. While data of GAL origin/distribution in the human eye are rather fragmentary and since recently the presence of GAL-receptors in the normal human eye has been reported, we here systematically search for sources of ocular GAL in the human eye. Human eyes (n=14) were prepared for single- and double-immunohistochemistry of GAL and neurofilaments (NF). Cross- and flat-mount sections were achieved; confocal laser-scanning microscopy was used for documentation. In the anterior eye, GAL-immunoreactivity (GAL-IR) was detected in basal layers of corneal epithelium, endothelium, and in nerve fibers and keratinocytes of the corneal stroma. In the conjunctiva, GAL-IR was seen throughout all epithelial cell layers. In the iris, sphincter and dilator muscle and endothelium of iris vessels displayed GAL-IR. It was also detected in stromal cells containing melanin granules, while these were absent in others. In the ciliary body, ciliary muscle and pigmented as well as non-pigmented ciliary epithelium displayed GAL-IR. In the retina, GAL-IR was detected in cells associated with the ganglion cell layer, and in endothelial cells of retinal blood vessels. In the choroid, nerve fibers of the choroidal stroma as well as fibers forming boutons and surrounding choroidal blood vessels displayed GAL-IR. Further, the majority of intrinsic choroidal neurons were GAL-positive, as revealed by co-localization-experiments with NF, while a minority displayed NF- or GAL-IR only. GAL-IR was also detected in choroidal melanocytes, as identified by the presence of intracellular melanin-granules, as well as in cells lacking melanin-granules, most likely representing macrophages. GAL-IR was detected in numerous cells and tissues throughout the anterior and posterior eye and might therefore be an important regulatory peptide for many aspects of ocular control. Upcoming studies in diseased tissue will help to clarify the role of GAL in ocular homeostasis.
Collapse
Affiliation(s)
- Alexandra Kaser-Eichberger
- University Clinic of Ophthalmology and Optometry, Research Program for Experimental Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, Salzburg, Austria.
| | - Andrea Trost
- University Clinic of Ophthalmology and Optometry, Research Program for Experimental Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, Salzburg, Austria
| | - Clemens Strohmaier
- University Clinic of Ophthalmology and Optometry, Research Program for Experimental Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, Salzburg, Austria
| | - Barbara Bogner
- University Clinic of Ophthalmology and Optometry, Research Program for Experimental Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, Salzburg, Austria
| | - Christian Runge
- University Clinic of Ophthalmology and Optometry, Research Program for Experimental Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, Salzburg, Austria
| | - Daniela Bruckner
- University Clinic of Ophthalmology and Optometry, Research Program for Experimental Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, Salzburg, Austria
| | - Bettina Hohberger
- Dept. of Ophthalmology, University Erlangen-Nuremberg, Erlangen, Germany
| | - Anselm Jünemann
- Dept. of Ophthalmology, University Rostock, Rostock, Germany
| | - Barbara Kofler
- Laura-Bassi Centre of Expertise, THERAPEP, Research Program of Receptor Biochemistry and Tumor Metabolism, Dept. of Pediatrics, Paracelsus Medical University/SALK, Salzburg, Austria
| | - Herbert A Reitsamer
- University Clinic of Ophthalmology and Optometry, Research Program for Experimental Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, Salzburg, Austria; Director of the Research Program for Experimental Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, Salzburg, Austria
| | - Falk Schrödl
- University Clinic of Ophthalmology and Optometry, Research Program for Experimental Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, Salzburg, Austria; Dept. of Anatomy, Paracelsus Medical University, Salzburg, Austria
| |
Collapse
|
27
|
The nervous system of the adult ascidian Ciona intestinalis Type A (Ciona robusta): Insights from transgenic animal models. PLoS One 2017. [PMID: 28651020 PMCID: PMC5484526 DOI: 10.1371/journal.pone.0180227] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The nervous system of ascidians is an excellent model system to provide insights into the evolutionary process of the chordate nervous system due to their phylogenetic positions as the sister group of vertebrates. However, the entire nervous system of adult ascidians has yet to be functionally and anatomically investigated. In this study, we have revealed the whole dorsal and siphon nervous system of the transgenic adult ascidian of Ciona intestinalis Type A (Ciona robusta) in which a Kaede reporter gene is expressed in a pan-neuronal fashion. The fluorescent signal of Kaede revealed the innervation patterns and distribution of neurons in the nervous system of Ciona. Precise microscopic observation demonstrated the clear innervation of the anterior and posterior main nerves to eight and six lobes of the oral and atrial siphons, respectively. Moreover, visceral nerves, previously identified as unpaired nerves, were found to be paired; one nerve was derived from the posterior end of the cerebral ganglion and the other from the right posterior nerve. This study further revealed the full trajectory of the dorsal strand plexus and paired visceral nerves on either side from the cerebral ganglion to the ovary, and precise innervation between the cerebral ganglion and the peripheral organs including the gonoduct, cupular organ, rectum and ovary. The differential innervation patterns of visceral nerves and the dorsal strand plexus indicate that the peripheral organs including the ovary undergo various neural regulations. Collectively, the present anatomical analysis revealed the major innervation of the dorsal and siphon nervous systems of adult Ciona.
Collapse
|
28
|
Jue NK, Batta-Lona PG, Trusiak S, Obergfell C, Bucklin A, O'Neill MJ, O'Neill RJ. Rapid Evolutionary Rates and Unique Genomic Signatures Discovered in the First Reference Genome for the Southern Ocean Salp, Salpa thompsoni (Urochordata, Thaliacea). Genome Biol Evol 2016; 8:3171-3186. [PMID: 27624472 PMCID: PMC5174732 DOI: 10.1093/gbe/evw215] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
A preliminary genome sequence has been assembled for the Southern Ocean salp, Salpa thompsoni (Urochordata, Thaliacea). Despite the ecological importance of this species in Antarctic pelagic food webs and its potential role as an indicator of changing Southern Ocean ecosystems in response to climate change, no genomic resources are available for S. thompsoni or any closely related urochordate species. Using a multiple-platform, multiple-individual approach, we have produced a 318,767,936-bp genome sequence, covering >50% of the estimated 602 Mb (±173 Mb) genome size for S. thompsoni. Using a nonredundant set of predicted proteins, >50% (16,823) of sequences showed significant homology to known proteins and ∼38% (12,151) of the total protein predictions were associated with Gene Ontology functional information. We have generated 109,958 SNP variant and 9,782 indel predictions for this species, serving as a resource for future phylogenomic and population genetic studies. Comparing the salp genome to available assemblies for four other urochordates, Botryllus schlosseri, Ciona intestinalis, Ciona savignyi and Oikopleura dioica, we found that S. thompsoni shares the previously estimated rapid rates of evolution for these species. High mutation rates are thus independent of genome size, suggesting that rates of evolution >1.5 times that observed for vertebrates are a broad taxonomic characteristic of urochordates. Tests for positive selection implemented in PAML revealed a small number of genes with sites undergoing rapid evolution, including genes involved in ribosome biogenesis and metabolic and immune process that may be reflective of both adaptation to polar, planktonic environments as well as the complex life history of the salps. Finally, we performed an initial survey of small RNAs, revealing the presence of known, conserved miRNAs, as well as novel miRNA genes; unique piRNAs; and mature miRNA signatures for varying developmental stages. Collectively, these resources provide a genomic foundation supporting S. thompsoni as a model species for further examination of the exceptional rates and patterns of genomic evolution shown by urochordates. Additionally, genomic data will allow for the development of molecular indicators of key life history events and processes and afford new understandings and predictions of impacts of climate change on this key species of Antarctic pelagic ecosystems.
Collapse
Affiliation(s)
- Nathaniel K Jue
- Department of Molecular and Cell Biology, Institute for Systems Genomics, University of Connecticut, CT.,Present address: School of Natural Sciences, California State University, Monterey Bay, CA
| | - Paola G Batta-Lona
- Department of Marine Sciences, University of Connecticut, CT.,Present address: Departamento de Biotecnologia Marina, CICESE, Ensenada, B.C. Mexico
| | - Sarah Trusiak
- Department of Molecular and Cell Biology, Institute for Systems Genomics, University of Connecticut, CT
| | - Craig Obergfell
- Department of Molecular and Cell Biology, Institute for Systems Genomics, University of Connecticut, CT
| | - Ann Bucklin
- Department of Marine Sciences, University of Connecticut, CT
| | - Michael J O'Neill
- Department of Molecular and Cell Biology, Institute for Systems Genomics, University of Connecticut, CT
| | - Rachel J O'Neill
- Department of Molecular and Cell Biology, Institute for Systems Genomics, University of Connecticut, CT
| |
Collapse
|
29
|
Osugi T, Son YL, Ubuka T, Satake H, Tsutsui K. RFamide peptides in agnathans and basal chordates. Gen Comp Endocrinol 2016; 227:94-100. [PMID: 26130238 DOI: 10.1016/j.ygcen.2015.06.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 06/16/2015] [Accepted: 06/17/2015] [Indexed: 12/12/2022]
Abstract
Since a peptide with a C-terminal Arg-Phe-NH2 (RFamide peptide) was first identified in the ganglia of the venus clam in 1977, RFamide peptides have been found in the nervous system of both invertebrates and vertebrates. In vertebrates, the RFamide peptide family includes gonadotropin-inhibitory hormone (GnIH), neuropeptide FF (NPFF), prolactin-releasing peptide (PrRP), pyroglutamylated RFamide peptide/26RFamide peptide (QRFP/26RFa), and kisspeptins (kiss1 and kiss2). They are involved in important functions such as the release of hormones, regulation of sexual or social behavior, pain transmission, reproduction, and feeding. In contrast to tetrapods and jawed fish, the information available on RFamide peptides in agnathans and basal chordates is limited, thus preventing further insights into the evolution of RFamide peptides in vertebrates. In this review, we focus on the previous research and recent advances in the studies on RFamide peptides in agnathans and basal chordates. In agnathans, the genes encoding GnIH, NPFF, and PrRP precursors and the mature peptides have been identified in lamprey (Petromyzon marinus) and hagfish (Paramyxine atami). Putative kiss1 and kiss2 genes have also been found in the genome database of lamprey. In basal chordates, namely, in amphioxus (Branchiostoma japonicum), a common ancestral form of GnIH and NPFF genes and their mature peptides, as well as the ortholog of the QRFP gene have been identified. The studies revealed that the number of orthologs of vertebrate RFamide peptides present in agnathans and basal chordates is greater than expected, suggesting that the vertebrate RFamide peptides might have emerged and expanded at an early stage of chordate evolution.
Collapse
Affiliation(s)
- Tomohiro Osugi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 1-1-1 Wakayamadai, Shimamoto, Mishima, Osaka 618-8503, Japan.
| | - You Lee Son
- Department of Biology and Center for Medical Life Science, Waseda University, Shinjuku, Tokyo 162-8480, Japan
| | - Takayoshi Ubuka
- Department of Biology and Center for Medical Life Science, Waseda University, Shinjuku, Tokyo 162-8480, Japan
| | - Honoo Satake
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 1-1-1 Wakayamadai, Shimamoto, Mishima, Osaka 618-8503, Japan
| | - Kazuyoshi Tsutsui
- Department of Biology and Center for Medical Life Science, Waseda University, Shinjuku, Tokyo 162-8480, Japan
| |
Collapse
|
30
|
Matsubara S, Kawada T, Sakai T, Aoyama M, Osugi T, Shiraishi A, Satake H. The significance of Ciona intestinalis as a stem organism in integrative studies of functional evolution of the chordate endocrine, neuroendocrine, and nervous systems. Gen Comp Endocrinol 2016; 227:101-8. [PMID: 26031189 DOI: 10.1016/j.ygcen.2015.05.010] [Citation(s) in RCA: 16] [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: 02/27/2015] [Revised: 05/13/2015] [Accepted: 05/16/2015] [Indexed: 11/19/2022]
Abstract
Ascidians are the closest phylogenetic neighbors to vertebrates and are believed to conserve the evolutionary origin in chordates of the endocrine, neuroendocrine, and nervous systems involving neuropeptides and peptide hormones. Ciona intestinalis harbors various homologs or prototypes of vertebrate neuropeptides and peptide hormones including gonadotropin-releasing hormones (GnRHs), tachykinins (TKs), and calcitonin, as well as Ciona-specific neuropeptides such as Ciona vasopressin, LF, and YFV/L peptides. Moreover, molecular and functional studies on Ciona tachykinin (Ci-TK) have revealed the novel molecular mechanism of inducing oocyte growth via up-regulation of vitellogenesis-associated protease activity, which is expected to be conserved in vertebrates. Furthermore, a series of studies on Ciona GnRH receptor paralogs have verified the species-specific regulation of GnRHergic signaling including unique signaling control via heterodimerization among multiple GnRH receptors. These findings confirm the remarkable significance of ascidians in investigations of the evolutionary processes of the peptidergic systems in chordates, leading to the promising advance in the research on Ciona peptides in the next stage based on the recent development of emerging technologies including genome-editing techniques, peptidomics-based multi-color staining, machine-learning prediction, and next-generation sequencing. These technologies and bioinformatic integration of the resultant "multi-omics" data will provide unprecedented insights into the comprehensive understanding of molecular and functional regulatory mechanisms of the Ciona peptides, and will eventually enable the exploration of both conserved and diversified endocrine, neuroendocrine, and nervous systems in the evolutionary lineage of chordates.
Collapse
Affiliation(s)
- Shin Matsubara
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 1-1-1 Wakayamadai, Shimamoto, Mishima, Osaka 618-8503, Japan
| | - Tsuyoshi Kawada
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 1-1-1 Wakayamadai, Shimamoto, Mishima, Osaka 618-8503, Japan
| | - Tsubasa Sakai
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 1-1-1 Wakayamadai, Shimamoto, Mishima, Osaka 618-8503, Japan
| | - Masato Aoyama
- Department of Biological Sciences, Faculty of Science, Nara Women's University, Kitauoyahigashi-machi, Nara 630-8506, Japan
| | - Tomohiro Osugi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 1-1-1 Wakayamadai, Shimamoto, Mishima, Osaka 618-8503, Japan
| | - Akira Shiraishi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 1-1-1 Wakayamadai, Shimamoto, Mishima, Osaka 618-8503, Japan
| | - Honoo Satake
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 1-1-1 Wakayamadai, Shimamoto, Mishima, Osaka 618-8503, Japan.
| |
Collapse
|
31
|
Hozumi A, Horie T, Sasakura Y. Neuronal map reveals the highly regionalized pattern of the juvenile central nervous system of the ascidian Ciona intestinalis. Dev Dyn 2015; 244:1375-93. [PMID: 26250096 DOI: 10.1002/dvdy.24317] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Revised: 07/28/2015] [Accepted: 08/02/2015] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND The dorsally located central nervous system (CNS) is an important hallmark of chordates. Among chordates, tunicate ascidians change their CNS remarkably by means of a metamorphosis from a highly regionalized larval CNS to an oval-shaped juvenile CNS without prominent morphological features. The neuronal organization of the CNS of ascidian tadpole larvae has been well described, but that in the CNS of postmetamorphosis juveniles has not been characterized well. RESULTS We investigated the number of neural cells, the number and position of differentiated neurons, and their axonal trajectories in the juvenile CNS of the ascidian Ciona intestinalis. The cell bodies of cholinergic, glutamatergic, and GABAergic/glycinergic neurons exhibited different localization patterns along the anterior-posterior axis in the juvenile CNS. Cholinergic neurons extended their axons toward the oral, atrial and body wall muscles and pharyngeal gill to regulate muscle contraction and ciliary movement. CONCLUSIONS Unlike its featureless shape, the juvenile CNS is highly patterned along the anterior-posterior axis. This patterning may be necessary for exerting multiple roles in the regulation of adult tissues distributed throughout the body. This basic information of the juvenile CNS of Ciona will allow in-depth studies of molecular mechanisms underlying the reconstruction of the CNS during ascidian metamorphosis.
Collapse
Affiliation(s)
- Akiko Hozumi
- Shimoda Marine Research Center, University of Tsukuba, Shimoda, Shizuoka, Japan
| | - Takeo Horie
- Japan Science and Technology Agency, PRESTO, Honcho, Kawaguchi, Saitama, Japan
| | - Yasunori Sasakura
- Shimoda Marine Research Center, University of Tsukuba, Shimoda, Shizuoka, Japan
| |
Collapse
|
32
|
De Haes W, Van Sinay E, Detienne G, Temmerman L, Schoofs L, Boonen K. Functional neuropeptidomics in invertebrates. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2014; 1854:812-26. [PMID: 25528324 DOI: 10.1016/j.bbapap.2014.12.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Revised: 11/27/2014] [Accepted: 12/10/2014] [Indexed: 10/24/2022]
Abstract
Neuropeptides are key messengers in almost all physiological processes. They originate from larger precursors and are extensively processed to become bioactive. Neuropeptidomics aims to comprehensively identify the collection of neuropeptides in an organism, organ, tissue or cell. The neuropeptidome of several invertebrates is thoroughly explored since they are important model organisms (and models for human diseases), disease vectors and pest species. The charting of the neuropeptidome is the first step towards understanding peptidergic signaling. This review will first discuss the latest developments in exploring the neuropeptidome. The physiological roles and modes of action of neuropeptides can be explored in two ways, which are largely orthogonal and therefore complementary. The first way consists of inferring the functions of neuropeptides by a forward approach where neuropeptide profiles are compared under different physiological conditions. Second is the reverse approach were neuropeptide collections are used to screen for receptor-binding. This is followed by localization studies and functional tests. This review will focus on how these different functional screening methods contributed to the field of invertebrate neuropeptidomics and expanded our knowledge of peptidergic signaling. This article is part of a Special Issue entitled: Neuroproteomics: Applications in Neuroscience and Neurology.
Collapse
Affiliation(s)
- Wouter De Haes
- Functional Genomics and Proteomics, Department of Biology, University of Leuven (KU Leuven), Naamsestraat 59, 3000 Leuven, Belgium
| | - Elien Van Sinay
- Functional Genomics and Proteomics, Department of Biology, University of Leuven (KU Leuven), Naamsestraat 59, 3000 Leuven, Belgium
| | - Giel Detienne
- Functional Genomics and Proteomics, Department of Biology, University of Leuven (KU Leuven), Naamsestraat 59, 3000 Leuven, Belgium
| | - Liesbet Temmerman
- Functional Genomics and Proteomics, Department of Biology, University of Leuven (KU Leuven), Naamsestraat 59, 3000 Leuven, Belgium
| | - Liliane Schoofs
- Functional Genomics and Proteomics, Department of Biology, University of Leuven (KU Leuven), Naamsestraat 59, 3000 Leuven, Belgium
| | - Kurt Boonen
- Functional Genomics and Proteomics, Department of Biology, University of Leuven (KU Leuven), Naamsestraat 59, 3000 Leuven, Belgium.
| |
Collapse
|
33
|
Thompson JM, Di Gregorio A. Insulin-like genes in ascidians: findings in Ciona and hypotheses on the evolutionary origins of the pancreas. Genesis 2014; 53:82-104. [PMID: 25378051 DOI: 10.1002/dvg.22832] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 10/13/2014] [Accepted: 10/16/2014] [Indexed: 12/22/2022]
Abstract
Insulin plays an extensively characterized role in the control of sugar metabolism, growth and homeostasis in a wide range of organisms. In vertebrate chordates, insulin is mainly produced by the beta cells of the endocrine pancreas, while in non-chordate animals insulin-producing cells are mainly found in the nervous system and/or scattered along the digestive tract. However, recent studies have indicated the notochord, the defining feature of the chordate phylum, as an additional site of expression of insulin-like peptides. Here we show that two of the three insulin-like genes identified in Ciona intestinalis, an invertebrate chordate with a dual life cycle, are first expressed in the developing notochord during embryogenesis and transition to distinct areas of the adult digestive tract after metamorphosis. In addition, we present data suggesting that the transcription factor Ciona Brachyury is involved in the control of notochord expression of at least one of these genes, Ciona insulin-like 2. Finally, we review the information currently available on insulin-producing cells in ascidians and on pancreas-related transcription factors that might control their expression.
Collapse
Affiliation(s)
- Jordan M Thompson
- Department of Cell and Developmental Biology, Weill Medical College of Cornell University, 1300 York Avenue, New York, New York
| | | |
Collapse
|
34
|
Kamiya C, Ohta N, Ogura Y, Yoshida K, Horie T, Kusakabe TG, Satake H, Sasakura Y. Nonreproductive role of gonadotropin-releasing hormone in the control of ascidian metamorphosis. Dev Dyn 2014; 243:1524-35. [PMID: 25130398 DOI: 10.1002/dvdy.24176] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 07/30/2014] [Accepted: 08/01/2014] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Gonadotropin-releasing hormones (GnRHs) are neuropeptides that play central roles in the reproduction of vertebrates. In the ascidian Ciona intestinalis, GnRHs and their receptors are expressed in the nervous systems at the larval stage, when animals are not yet capable of reproduction, suggesting that the hormones have non-reproductive roles. RESULTS We showed that GnRHs in Ciona are involved in the animal's metamorphosis by regulating tail absorption and adult organ growth. Absorption of the larval tail and growth of the adult organs are two major events in the metamorphosis of ascidians. When larvae were treated with GnRHs, they completed tail absorption more frequently than control larvae. cAMP was suggested to be a second messenger for the induction of tail absorption by GnRHs. tGnRH-3 and tGnRH-5 (the "t" indicates "tunicate") inhibited the growth of adult organs by arresting cell cycle progression in parallel with the promotion of tail absorption. CONCLUSIONS This study provides new insights into the molecular mechanisms of ascidian metamorphosis conducted by non-reproductive GnRHs.
Collapse
Affiliation(s)
- Chisato Kamiya
- Shimoda Marine Research Center, University of Tsukuba, Shimoda, Shizuoka, Japan
| | | | | | | | | | | | | | | |
Collapse
|
35
|
Hayakawa E, Landuyt B, Baggerman G, Cuyvers R, Lavigne R, Luyten W, Schoofs L. Peptidomic analysis of human reflex tear fluid. Peptides 2013; 42:63-9. [PMID: 23228955 DOI: 10.1016/j.peptides.2012.11.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Revised: 11/20/2012] [Accepted: 11/20/2012] [Indexed: 12/19/2022]
Abstract
Tear fluid is a complex mixture of biological compounds, including carbohydrates, lipids, electrolytes, proteins, and peptides. Despite the physiological importance of tear fluid, little is known about the identity of its endogenous peptides. In this study, we analyzed and identified naturally occurring peptide molecules in human reflex tear fluid by means of LC-MALDI-TOF-TOF. Tandem MS analyses revealed 30 peptides, most of which have not been identified before. Twenty-six peptides are derived from the proline-rich protein 4 and 4 peptides are derived from the polymeric immunoglobulin receptor. Based on their structural characteristics, we suggest that the identified tear fluid peptides contribute to the protective environment of the ocular surface.
Collapse
Affiliation(s)
- Eisuke Hayakawa
- Research Group of Functional Genomics and Proteomics, KU Leuven, B-3000 Leuven, Belgium.
| | | | | | | | | | | | | |
Collapse
|
36
|
Satake H, Matsubara S, Aoyama M, Kawada T, Sakai T. GPCR Heterodimerization in the Reproductive System: Functional Regulation and Implication for Biodiversity. Front Endocrinol (Lausanne) 2013; 4:100. [PMID: 23966979 PMCID: PMC3744054 DOI: 10.3389/fendo.2013.00100] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Accepted: 07/31/2013] [Indexed: 01/24/2023] Open
Abstract
A G protein-coupled receptor (GPCR) functions not only as a monomer or homodimer but also as a heterodimer with another GPCR. GPCR heterodimerization results in the modulation of the molecular functions of the GPCR protomer, including ligand binding affinity, signal transduction, and internalization. There has been a growing body of reports on heterodimerization of multiple GPCRs expressed in the reproductive system and the resultant functional modulation, suggesting that GPCR heterodimerization is closely associated with reproduction including the secretion of hormones and the growth and maturation of follicles and oocytes. Moreover, studies on heterodimerization among paralogs of gonadotropin-releasing hormone (GnRH) receptors of a protochordate, Ciona intestinalis, verified the species-specific regulation of the functions of GPCRs via multiple GnRH receptor pairs. These findings indicate that GPCR heterodimerization is also involved in creating biodiversity. In this review, we provide basic and current knowledge regarding GPCR heterodimers and their functional modulation, and explore the biological significance of GPCR heterodimerization.
Collapse
Affiliation(s)
- Honoo Satake
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Osaka, Japan
- *Correspondence: Honoo Satake, Suntory Foundation for Life Sciences, Bioorganic Research Institute, 1-1-1 Wakayamadai, Shimamoto, Mishima, Osaka 618-8503, Japan e-mail:
| | - Shin Matsubara
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Osaka, Japan
| | - Masato Aoyama
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Osaka, Japan
| | - Tsuyoshi Kawada
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Osaka, Japan
| | - Tsubasa Sakai
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Osaka, Japan
| |
Collapse
|
37
|
Enhancer activity sensitive to the orientation of the gene it regulates in the chordate genome. Dev Biol 2012; 375:79-91. [PMID: 23274690 DOI: 10.1016/j.ydbio.2012.12.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Revised: 11/22/2012] [Accepted: 12/13/2012] [Indexed: 12/26/2022]
Abstract
Enhancers are flexible in terms of their location and orientation relative to the genes they regulate. However, little is known about whether the flexibility can be applied in every combination of enhancers and genes. Enhancer detection with transposable elements is a powerful method to identify enhancers in the genome and to create marker lines expressing fluorescent proteins in a tissue-specific manner. In the chordate Ciona intestinalis, this method has been established with a Tc1/mariner superfamily transposon Minos. Previously, we created the enhancer detection line E[MiTSAdTPOG]15 (E15) that specifically expresses green fluorescent protein (GFP) in the central nervous system (CNS) after metamorphosis. In this study, we identified the causal insertion site of the transgenic line. There are two genes flanking the causal insertion of the E15 line, and the genomic region around the insertion site contains the enhancers responsible for the expression in the endostyle and gut in addition to the CNS. We found that the endostyle and gut enhancers show sensitivity to the orientation of the GFP gene for their enhancer activity. Namely, the enhancers cannot enhance the expression of GFP which is inserted at the same orientation as the E15 line, while the enhancers can enhance GFP expression inserted at the opposite orientation. The CNS enhancer can enhance GFP expression in both orientations. The DNA element adjacent to the endostyle enhancer is responsible for the orientation sensitivity of the enhancer. The different sensitivity of the enhancers to the orientation of the transgene is a cause of CNS-specific GFP expression in the E15 line.
Collapse
|
38
|
Sakai T, Aoyama M, Kawada T, Kusakabe T, Tsuda M, Satake H. Evidence for differential regulation of GnRH signaling via heterodimerization among GnRH receptor paralogs in the protochordate, Ciona intestinalis. Endocrinology 2012; 153:1841-9. [PMID: 22294747 DOI: 10.1210/en.2011-1668] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The endocrine and neuroendocrine systems for reproductive functions have diversified as a result of the generation of species-specific paralogs of peptide hormones and their receptors including GnRH and their receptors (GnRHR), which belong to the class A G protein-coupled receptor family. A protochordate, Ciona intestinalis, has been found to possess seven GnRH (tGnRH-3 to -8 and Ci-GnRH-X) and four GnRHR (Ci-GnRHR1 to -4). Moreover, Ci-GnRHR4 (R4) does not bind to any Ciona GnRH and activate any signaling pathways. Here we show novel functional diversification of GnRH signaling pathways via G protein-coupled receptor heterodimerization among Ciona GnRHR. R4 was shown to heterodimerize with R2 specifically in test cells of vitellogenic oocytes by coimmunoprecipitation. The R2-R4 heterodimerization in human embryonic kidney 293 cells cotransfected with R2 and R4 was also observed by coimmunoprecipitation and fluorescent energy transfer analyses. Of particular interest is that the R2-R4 heterodimer decreases the cAMP production in a nonligand-selective manner via shift of activation of Gs protein to Gi protein by R2, compared with R2 monomer/homodimer. Considering that the R1-R4 heterodimer elicits 10-fold more potent Ca²⁺ mobilization than R1 monomer/homodimer in a ligand-selective manner but does not affect cAMP production, these results indicate that R4 regulates differential GnRH signaling cascades via heterodimerization with R1 and R2 as an endogenous allosteric modulator. Collectively, the present study suggests that the heterodimerization among GnRHR paralogs, including the species-specific orphan receptor subtype, is involved in rigorous and diversified GnRHergic signaling of the protochordate, which lacks a hypothalamus-pituitary gonad axis.
Collapse
Affiliation(s)
- Tsubasa Sakai
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Osaka 618-8503, Japan
| | | | | | | | | | | |
Collapse
|
39
|
Sekiguchi T, Ogasawara M, Satake H. Molecular and functional characterization of cionin receptors in the ascidian, Ciona intestinalis: the evolutionary origin of the vertebrate cholecystokinin/gastrin family. J Endocrinol 2012; 213:99-106. [PMID: 22289502 DOI: 10.1530/joe-11-0410] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cholecystokinin (CCK) and gastrin are vertebrate brain-gut peptides featured by a sulfated tyrosine residue and a C-terminally amidated tetrapeptide consensus sequence. Cionin, identified in the ascidian, Ciona intestinalis, the closest species to vertebrates, harbors two sulfated tyrosines and the CCK/gastrin consensus tetrapeptide sequence. While a putative cionin receptor, cior, was cloned, the ligand-receptor relationship between cionin and CioR remains unidentified. Here, we identify two cionin receptors, CioR1 and CioR2, which are the aforementioned putative cionin receptor and its novel paralog respectively. Phylogenetic analysis revealed that CioRs are homologous to vertebrate CCK receptors (CCKRs) and diverged from a common ancestor in the Ciona-specific lineage. Cionin activates intracellular calcium mobilization in cultured cells expressing CioR1 or CioR2. Monosulfated and nonsulfated cionin exhibited less potent or no activity, indicating that CioRs possess pharmacological features similar to the vertebrate CCK-specific receptor CCK1R, rather than its subtype CCK2R, given that a sulfated tyrosine in CCK is required for binding to CCK1R, but not to CCK2R. Collectively, the present data reveal that CioRs share a common ancestor with vertebrate CCKRs and indicate that CCK and CCK1R form the ancestral ligand-receptor pair in the vertebrate CCK/gastrin system. Cionin is expressed in the neural complex, digestive organs, oral siphon and atrial siphons, whereas the expression of ciors was detected mainly in these tissues and the ovary. Furthermore, cioninergic neurons innervate both of the siphons. These results suggest that cionin is involved in the regulation of siphonal functions.
Collapse
Affiliation(s)
- Toshio Sekiguchi
- Suntory Foundation for Life Sciences Bioorganic Research Institute, Wakayamadai 1-1-1, Shimamoto-cho, Mishima-gun, Osaka, Japan
| | | | | |
Collapse
|