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Shikina S, Yoshioka Y, Chiu YL, Uchida T, Chen E, Cheng YC, Lin TC, Chu YL, Kanda M, Kawamitsu M, Fujie M, Takeuchi T, Zayasu Y, Satoh N, Shinzato C. Genome and tissue-specific transcriptomes of the large-polyp coral, Fimbriaphyllia (Euphyllia) ancora: a recipe for a coral polyp. Commun Biol 2024; 7:899. [PMID: 39048698 PMCID: PMC11269664 DOI: 10.1038/s42003-024-06544-4] [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: 12/21/2023] [Accepted: 07/03/2024] [Indexed: 07/27/2024] Open
Abstract
Coral polyps are composed of four tissues; however, their characteristics are largely unexplored. Here we report biological characteristics of tentacles (Te), mesenterial filaments (Me), body wall (Bo), and mouth with pharynx (MP), using comparative genomic, morpho-histological, and transcriptomic analyses of the large-polyp coral, Fimbriaphyllia ancora. A draft F. ancora genome assembly of 434 Mbp was created. Morpho-histological and transcriptomic characterization of the four tissues showed that they have distinct differences in structure, primary cellular composition, and transcriptional profiles. Tissue-specific, highly expressed genes (HEGs) of Te are related to biological defense, predation, and coral-algal symbiosis. Me expresses multiple digestive enzymes, whereas Bo expresses innate immunity and biomineralization-related molecules. Many receptors for neuropeptides and neurotransmitters are expressed in MP. This dataset and new insights into tissue functions will facilitate a deeper understanding of symbiotic biology, immunology, biomineralization, digestive biology, and neurobiology in corals.
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Affiliation(s)
- Shinya Shikina
- Institute of Marine Environment and Ecology, National Taiwan Ocean University, Keelung, Taiwan.
- Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung, Taiwan.
| | - Yuki Yoshioka
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan
| | - Yi-Ling Chiu
- Institute of Marine Environment and Ecology, National Taiwan Ocean University, Keelung, Taiwan
| | - Taiga Uchida
- Atmosphere and Ocean Research Institute, The University of Tokyo, Chiba, Japan
| | - Emma Chen
- Institute of Marine Environment and Ecology, National Taiwan Ocean University, Keelung, Taiwan
| | - Yin-Chu Cheng
- Institute of Marine Environment and Ecology, National Taiwan Ocean University, Keelung, Taiwan
| | - Tzu-Chieh Lin
- Institute of Marine Environment and Ecology, National Taiwan Ocean University, Keelung, Taiwan
| | - Yu-Ling Chu
- Institute of Marine Environment and Ecology, National Taiwan Ocean University, Keelung, Taiwan
| | - Miyuki Kanda
- DNA Sequencing Center Section, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan
| | - Mayumi Kawamitsu
- DNA Sequencing Center Section, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan
| | - Manabu Fujie
- DNA Sequencing Center Section, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan
| | - Takeshi Takeuchi
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan
| | - Yuna Zayasu
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan
| | - Noriyuki Satoh
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan
| | - Chuya Shinzato
- Atmosphere and Ocean Research Institute, The University of Tokyo, Chiba, Japan.
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Thoma V, Sakai S, Nagata K, Ishii Y, Maruyama S, Abe A, Kondo S, Kawata M, Hamada S, Deguchi R, Tanimoto H. On the origin of appetite: GLWamide in jellyfish represents an ancestral satiety neuropeptide. Proc Natl Acad Sci U S A 2023; 120:e2221493120. [PMID: 37011192 PMCID: PMC10104569 DOI: 10.1073/pnas.2221493120] [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: 01/03/2023] [Accepted: 01/20/2023] [Indexed: 04/05/2023] Open
Abstract
Food intake is regulated by internal state. This function is mediated by hormones and neuropeptides, which are best characterized in popular model species. However, the evolutionary origins of such feeding-regulating neuropeptides are poorly understood. We used the jellyfish Cladonema to address this question. Our combined transcriptomic, behavioral, and anatomical approaches identified GLWamide as a feeding-suppressing peptide that selectively inhibits tentacle contraction in this jellyfish. In the fruit fly Drosophila, myoinhibitory peptide (MIP) is a related satiety peptide. Surprisingly, we found that GLWamide and MIP were fully interchangeable in these evolutionarily distant species for feeding suppression. Our results suggest that the satiety signaling systems of diverse animals share an ancient origin.
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Affiliation(s)
- Vladimiros Thoma
- Graduate School of Life Sciences, Tohoku University, Sendai980-8577, Japan
- Department of Biology, Miyagi University of Education, Aoba-ku, Sendai980-0845, Japan
| | - Shuhei Sakai
- Graduate School of Life Sciences, Tohoku University, Sendai980-8577, Japan
| | - Koki Nagata
- Graduate School of Life Sciences, Tohoku University, Sendai980-8577, Japan
| | - Yuu Ishii
- Department of Biology, Miyagi University of Education, Aoba-ku, Sendai980-0845, Japan
- Department of Ecological Developmental Adaptability Life Sciences, Graduate School of Life Sciences, Tohoku University, Aobaku, Sendai980-8578, Japan
| | - Shinichiro Maruyama
- Department of Ecological Developmental Adaptability Life Sciences, Graduate School of Life Sciences, Tohoku University, Aobaku, Sendai980-8578, Japan
- Department of Life Science, Graduate School of Humanities and Sciences, Ochanomizu University, Bunkyo-ku, Tokyo112-8610, Japan
| | - Ayako Abe
- Graduate School of Life Sciences, Tohoku University, Sendai980-8577, Japan
| | - Shu Kondo
- Department of Biological Science and Technology, Faculty of Advanced Engineering, Tokyo University of Science, Katsushika-ku, Tokyo125-8585, Japan
- Invertebrate Genetics Laboratory, National Institute of Genetics, Mishima, Shizuoka411-8540, Japan
| | - Masakado Kawata
- Department of Ecological Developmental Adaptability Life Sciences, Graduate School of Life Sciences, Tohoku University, Aobaku, Sendai980-8578, Japan
| | - Shun Hamada
- Department of Food and Health Sciences, International College of Arts and Sciences, Fukuoka Women’s University, Fukuoka813-8529, Japan
| | - Ryusaku Deguchi
- Department of Biology, Miyagi University of Education, Aoba-ku, Sendai980-0845, Japan
| | - Hiromu Tanimoto
- Graduate School of Life Sciences, Tohoku University, Sendai980-8577, Japan
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Hauser F, Koch TL, Grimmelikhuijzen CJP. Review: The evolution of peptidergic signaling in Cnidaria and Placozoa, including a comparison with Bilateria. Front Endocrinol (Lausanne) 2022; 13:973862. [PMID: 36213267 PMCID: PMC9545775 DOI: 10.3389/fendo.2022.973862] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 08/26/2022] [Indexed: 11/13/2022] Open
Abstract
Bilateria have bilateral symmetry and are subdivided into Deuterostomia (animals like vertebrates) and Protostomia (animals like insects and mollusks). Neuropeptides occur in both Proto- and Deuterostomia and they are frequently structurally related across these two lineages. For example, peptides belonging to the oxytocin/vasopressin family exist in both clades. The same is true for the G protein-coupled receptors (GPCRs) of these peptides. These observations suggest that these neuropeptides and their GPCRs were already present in the common ancestor of Proto- and Deuterostomia, which lived about 700 million years ago (MYA). Furthermore, neuropeptides and their GPCRs occur in two early-branching phyla that diverged before the emergence of Bilateria: Cnidaria (animals like corals and sea anemones), and Placozoa (small disk-like animals, feeding on algae). The sequences of these neuropeptides and their GPCRs, however, are not closely related to those from Bilateria. In addition, cnidarian neuropeptides and their receptors are not closely related to those from Placozoa. We propose that the divergence times between Cnidaria, Placozoa, and Bilateria might be too long for recognizing sequence identities. Leucine-rich repeats-containing GPCRs (LGRs) are a special class of GPCRs that are characterized by a long N-terminus containing 10-20 leucine-rich domains, which are used for ligand binding. Among the ligands for LGRs are dimeric glycoprotein hormones, and insulin-like peptides, such as relaxin. LGRs have been found not only in Proto- and Deuterostomia, but also in early emerging phyla, such as Cnidaria and Placozoa. Humans have eight LGRs. In our current review, we have revisited the annotations of LGRs from the sea anemone Nematostella vectensis and the placozoan Trichoplax adhaerens. We identified 13 sea anemone LGRs and no less than 46 LGRs from T. adhaerens. All eight human LGRs appear to have orthologues in sea anemones and placozoans. LGRs and their ligands, therefore, have a long evolutionary history, going back to the common ancestor of Cnidaria and Placozoa.
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Affiliation(s)
- Frank Hauser
- Section for Cell and Neurobiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Thomas L. Koch
- Section for Cell and Neurobiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
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Marciniak P, Pacholska-Bogalska J, Ragionieri L. Neuropeptidomes of Tenebrio molitor L. and Zophobas atratus Fab. (Coleoptera, Polyphaga: Tenebrionidae). J Proteome Res 2022; 21:2247-2260. [PMID: 36107737 PMCID: PMC9552230 DOI: 10.1021/acs.jproteome.1c00694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Paweł Marciniak
- Department of Animal Physiology and Developmental Biology, Institute of Experimental Biology, Faculty of Biology, Adam Mickiewicz University, Poznań 61-614, Poland
| | - Joanna Pacholska-Bogalska
- Department of Animal Physiology and Developmental Biology, Institute of Experimental Biology, Faculty of Biology, Adam Mickiewicz University, Poznań 61-614, Poland
| | - Lapo Ragionieri
- Department for Biology, Institute of Zoology, University of Cologne, Cologne 50674, Germany
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Rischer M, Guo H, Beemelmanns C. Signalling molecules inducing metamorphosis in marine organisms. Nat Prod Rep 2022; 39:1833-1855. [PMID: 35822257 DOI: 10.1039/d1np00073j] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Covering: findings from early 1980s until early 2022Microbial-derived cues of marine biofilms induce settlement and metamorphosis of marine organisms, a process responsible for the emergence of diverse flora and fauna in marine habitats. Although this phenomenon is known for more than 80 years, the research field has only recently gained much momentum. Here, we summarize the currently existing biochemical and microbial knowledge about microbial signalling molecules, con-specific signals, and synthetic compounds that induce or prevent recruitment, settlement, and metamorphosis in invertebrate larvae. We discuss the possible modes of action and conclude with perspectives for future research directions in the field of marine chemical ecology.
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Affiliation(s)
- Maja Rischer
- Chemical Biology of Microbe-Host Interactions, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute (HKI), Beutenbergstraße 11a, Jena, 07745, Germany.
| | - Huijuan Guo
- Chemical Biology of Microbe-Host Interactions, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute (HKI), Beutenbergstraße 11a, Jena, 07745, Germany.
| | - Christine Beemelmanns
- Chemical Biology of Microbe-Host Interactions, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute (HKI), Beutenbergstraße 11a, Jena, 07745, Germany. .,Biochemistry of Microbial Metabolism, Institute of Biochemistry, Leipzig University, Johannisallee 21-23, Leipzig 04103, Germany
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6
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Zhang Y, Shikina S, Ho YY, Chiu YL, I-Chen Yao J, Zatylny-Gaudin C, Dufour S, Chang CF. Involvement of RFamide neuropeptides in polyp contraction of the adult scleractinian corals Euphyllia ancora and Stylophora pistillata. Gen Comp Endocrinol 2021; 314:113905. [PMID: 34534544 DOI: 10.1016/j.ygcen.2021.113905] [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: 05/06/2021] [Revised: 09/05/2021] [Accepted: 09/11/2021] [Indexed: 11/26/2022]
Abstract
The distribution and functions of neurons in scleractinian corals remain largely unknown. This study focused on the Arg-Phe amide family of neuropeptides (RFamides), which have been shown to be involved in a variety of biological processes in animals, and performed molecular identification and characterization in the adult scleractinian coral Euphyllia ancora. The deduced amino acid sequence of the identified RFamide preprohormone was predicted to contain 20 potential neuropeptides, including 1 Pro-Gly-Arg-Phe (PGRF) amide and 15 Gln-Gly-Arg-Phe (QGRF) amide peptides. Tissue distribution analysis showed that the level of transcripts in the tentacles was significantly higher than that in other polyp tissues. Immunohistochemical analysis with the FMRFamide antibody showed that RFamide neurons were mainly distributed in the epidermis of the tentacles and mouth with pharynx. Treatment of E. ancora polyps with synthetic QGRFamide peptides induced polyp contraction. The induction of polyp contraction by QGRFamide peptide treatment was also observed in another scleractinian coral, Stylophora pistillata. These results strongly suggested that RFamides play a role in the regulation of polyp contraction in adult scleractinians.
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Affiliation(s)
- Yan Zhang
- Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung, Taiwan; Zhejiang Marine Fisheries Research Institute, Zhejiang, China; Marine and Fishery Research Institute, Zhejiang Ocean University, Zhejiang, China
| | - Shinya Shikina
- Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung, Taiwan; Institute of Marine Environment and Ecology, National Taiwan Ocean University, Keelung, Taiwan.
| | - Yu-Ying Ho
- Department of Aquaculture, National Taiwan Ocean University, Keelung, Taiwan
| | - Yi-Ling Chiu
- Atmosphere and Ocean Research Institute, The University of Tokyo, Chiba, Japan
| | - Jack I-Chen Yao
- Department of Aquaculture, National Taiwan Ocean University, Keelung, Taiwan
| | - Céline Zatylny-Gaudin
- Laboratory Biology of Aquatic Organisms and Ecosystems (BOREA), University of Caen-Normandy, Muséum National d'Histoire Naturelle, CNRS, IRD, Sorbonne Université, Université des Antilles, 14032, Caen, France and 75231 Paris Cedex 05, France
| | - Sylvie Dufour
- Laboratory Biology of Aquatic Organisms and Ecosystems (BOREA), University of Caen-Normandy, Muséum National d'Histoire Naturelle, CNRS, IRD, Sorbonne Université, Université des Antilles, 14032, Caen, France and 75231 Paris Cedex 05, France
| | - Ching-Fong Chang
- Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung, Taiwan; Department of Aquaculture, National Taiwan Ocean University, Keelung, Taiwan.
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Li R, Yu H, Li A, Yu C, Li P. Refinement and Neutralization Evaluation of the F(ab') 2 Type of Antivenom against the Deadly Jellyfish Nemopilema nomurai Toxins. Int J Mol Sci 2021; 22:ijms222312672. [PMID: 34884477 PMCID: PMC8657884 DOI: 10.3390/ijms222312672] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 11/15/2021] [Accepted: 11/16/2021] [Indexed: 12/31/2022] Open
Abstract
Jellyfish stings threaten people's health and even life in coastal areas worldwide. Nemopilema nomurai is one of the most dangerous jellyfish in the East Asian Marginal Seas, which not only stings hundreds of thousands of people every year but also is assumed to be responsible for most deaths by jellyfish stings in China. However, there is no effective first-aid drug, such as antivenoms, for the treatment of severe stings by N. nomurai to date. In this study, we prepared a N. nomurai antiserum from rabbits using inactivated N. nomurai toxins (NnTXs) and isolated the IgG type of antivenom (IgG-AntiNnTXs) from the antiserum. Subsequently, IgG-AntiNnTXs were refined with multiple optimizations to remove Fc fragments. Finally, the F(ab')2 type of antivenom (F(ab')2-AntiNnTXs) was purified using Superdex 200 and protein A columns. The neutralization efficacy of both types of antivenom was analyzed in vitro and in vivo, and the results showed that both IgG and F(ab')2 types of antivenom have some neutralization effect on the metalloproteinase activity of NnTXs in vitro and could also decrease the mortality of mice in the first 4 h after injection. This study provides some useful information for the development of an effective antivenom for N. nomurai stings in the future.
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Affiliation(s)
- Rongfeng Li
- Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; (H.Y.); (A.L.); (C.Y.)
- Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China
- Correspondence: (R.L.); (P.L.); Tel.: +86-532-8289-8512 (R.L.); +86-532-8289-8707 (P.L.)
| | - Huahua Yu
- Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; (H.Y.); (A.L.); (C.Y.)
- Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China
| | - Aoyu Li
- Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; (H.Y.); (A.L.); (C.Y.)
- College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chunlin Yu
- Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; (H.Y.); (A.L.); (C.Y.)
- College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Pengcheng Li
- Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; (H.Y.); (A.L.); (C.Y.)
- Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China
- Correspondence: (R.L.); (P.L.); Tel.: +86-532-8289-8512 (R.L.); +86-532-8289-8707 (P.L.)
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8
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Nielsen SKD, Koch TL, Wiisbye SH, Grimmelikhuijzen CJP, Garm A. Neuropeptide expression in the box jellyfish Tripedalia cystophora-New insights into the complexity of a "simple" nervous system. J Comp Neurol 2021; 529:2865-2882. [PMID: 33660861 DOI: 10.1002/cne.25133] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 02/11/2021] [Accepted: 02/23/2021] [Indexed: 01/09/2023]
Abstract
Box jellyfish have an elaborate visual system and perform advanced visually guided behaviors. However, the rhopalial nervous system (RNS), believed to be the main visual processing center, only has 1000 neurons in each of the four eye carrying rhopalia. We have examined the detailed structure of the RNS of the box jellyfish Tripedalia cystophora, using immunolabeling with antibodies raised against four putative neuropeptides (T. cystophora RFamide, VWamide, RAamide, and FRamide). In the RNS, T. cystophora RF-, VW-, and RAamide antibodies stain sensory neurons, the pit eyes, the neuropil, and peptide-specific subpopulations of stalk-associated neurons and giant neurons. Furthermore, RFamide ir+ neurites are seen in the epidermal stalk nerve, whereas VWamide antibodies stain the gastrodermal stalk nerve. RFamide has the most widespread expression including in the ring and radial nerves, the pedalium nerve plexus, and the tentacular nerve net. RAamide is the putative neurotransmitter in the motor neurons of the subumbrellar nerve net, and VWamide is a potential marker for neuronal differentiation as it is found in subpopulations of undifferentiated cells both in the rhopalia and in the bell. The results from the FRamide antibodies were not included as only few cells were stained, and in an unreproducible way. Our studies show hitherto-unseen details of the nervous system of T. cystophora and allowed us to identify specific functional groups of neurons. This identification is important for understanding visual processing in the RNS and enables experimental work, directly addressing the role of the different neuropeptides in vision.
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Affiliation(s)
- Sofie K D Nielsen
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Thomas L Koch
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Sofus H Wiisbye
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | | | - Anders Garm
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
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9
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Krasovec G, Pottin K, Rosello M, Quéinnec É, Chambon JP. Apoptosis and cell proliferation during metamorphosis of the planula larva of Clytia hemisphaerica (Hydrozoa, Cnidaria). Dev Dyn 2021; 250:1739-1758. [PMID: 34036636 DOI: 10.1002/dvdy.376] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 05/19/2021] [Accepted: 05/20/2021] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Metamorphosis in marine species is characterized by profound changes at the ecophysiological, morphological, and cellular levels. The cnidarian Clytia hemisphaerica exhibits a triphasic life cycle that includes a planula larva, a colonial polyp, and a sexually reproductive medusa. Most studies so far have focused on the embryogenesis of this species, whereas its metamorphosis has been only partially studied. RESULTS We investigated the main morphological changes of the planula larva of Clytia during the metamorphosis, and the associated cell proliferation and apoptosis. Based on our observations of planulae at successive times following artificial metamorphosis induction using GLWamide, we subdivided the Clytia's metamorphosis into a series of eight morphological stages occurring during a pre-settlement phase (from metamorphosis induction to planula ready for settlement) and the post-settlement phase (from planula settlement to primary polyp). Drastic morphological changes prior to definitive adhesion to the substrate were accompanied by specific patterns of stem-cell proliferation as well as apoptosis in both ectoderm and endoderm. Further waves of apoptosis occurring once the larva has settled were associated with morphogenesis of the primary polyp. CONCLUSION Clytia larval metamorphosis is characterized by distinct patterns of apoptosis and cell proliferation during the pre-settlement phase and the settled planula-to-polyp transformation.
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Affiliation(s)
- Gabriel Krasovec
- Sorbonne Université, CNRS, Institut de Biologie Paris Seine, IBPS, Evolution Paris Seine, Paris, France
| | - Karen Pottin
- Sorbonne Université, CNRS, Institut de Biologie Paris Seine, IBPS, Evolution Paris Seine, Paris, France
| | - Marion Rosello
- Sorbonne Université, CNRS, Institut de Biologie Paris Seine, IBPS, Evolution Paris Seine, Paris, France
| | - Éric Quéinnec
- Sorbonne Université, CNRS, Institut de Biologie Paris Seine, IBPS, Evolution Paris Seine, Paris, France.,Institut de Systématique, Evolution, Biodiversité, Sorbonne Université, Muséum National d'histoire Naturelle, Paris Cedex, France
| | - Jean-Philippe Chambon
- Sorbonne Université, CNRS, Institut de Biologie Paris Seine, IBPS, Evolution Paris Seine, Paris, France.,Centre de Recherche de Biologie Cellulaire de Montpellier (CRBM), Montpellier University, CNRS, Montpellier, France
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10
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Jékely G. The chemical brain hypothesis for the origin of nervous systems. Philos Trans R Soc Lond B Biol Sci 2021; 376:20190761. [PMID: 33550946 PMCID: PMC7935135 DOI: 10.1098/rstb.2019.0761] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/25/2020] [Indexed: 12/13/2022] Open
Abstract
In nervous systems, there are two main modes of transmission for the propagation of activity between cells. Synaptic transmission relies on close contact at chemical or electrical synapses while volume transmission is mediated by diffusible chemical signals and does not require direct contact. It is possible to wire complex neuronal networks by both chemical and synaptic transmission. Both types of networks are ubiquitous in nervous systems, leading to the question which of the two appeared first in evolution. This paper explores a scenario where chemically organized cellular networks appeared before synapses in evolution, a possibility supported by the presence of complex peptidergic signalling in all animals except sponges. Small peptides are ideally suited to link up cells into chemical networks. They have unlimited diversity, high diffusivity and high copy numbers derived from repetitive precursors. But chemical signalling is diffusion limited and becomes inefficient in larger bodies. To overcome this, peptidergic cells may have developed projections and formed synaptically connected networks tiling body surfaces and displaying synchronized activity with pulsatile peptide release. The advent of circulatory systems and neurohemal organs further reduced the constraint imposed on chemical signalling by diffusion. This could have contributed to the explosive radiation of peptidergic signalling systems in stem bilaterians. Neurosecretory centres in extant nervous systems are still predominantly chemically wired and coexist with the synaptic brain. This article is part of the theme issue 'Basal cognition: multicellularity, neurons and the cognitive lens'.
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Affiliation(s)
- Gáspár Jékely
- Living Systems Institute, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
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11
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Lechable M, Jan A, Duchene A, Uveira J, Weissbourd B, Gissat L, Collet S, Gilletta L, Chevalier S, Leclère L, Peron S, Barreau C, Lasbleiz R, Houliston E, Momose T. An improved whole life cycle culture protocol for the hydrozoan genetic model Clytia hemisphaerica. Biol Open 2020; 9:bio051268. [PMID: 32994186 PMCID: PMC7657476 DOI: 10.1242/bio.051268] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 09/07/2020] [Indexed: 12/17/2022] Open
Abstract
The jellyfish species Clytia hemisphaerica (Cnidaria, Hydrozoa) has emerged as a new experimental model animal in the last decade. Favorable characteristics include a fully transparent body suitable for microscopy, daily gamete production and a relatively short life cycle. Furthermore, whole genome sequence assembly and efficient gene editing techniques using CRISPR/Cas9 have opened new possibilities for genetic studies. The quasi-immortal vegetatively-growing polyp colony stage provides a practical means to maintain mutant strains. In the context of developing Clytia as a genetic model, we report here an improved whole life cycle culture method including an aquarium tank system designed for culture of the tiny jellyfish form. We have compared different feeding regimes using Artemia larvae as food and demonstrate that the stage-dependent feeding control is the key for rapid and reliable medusa and polyp rearing. Metamorphosis of the planula larvae into a polyp colony can be induced efficiently using a new synthetic peptide. The optimized procedures detailed here make it practical to generate genetically modified Clytia strains and to maintain their whole life cycle in the laboratory.This article has an associated First Person interview with the two first authors of the paper.
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Affiliation(s)
- Marion Lechable
- Sorbonne Université, CNRS, Institut de la Mer de Villefranche, UMR7009 Laboratoire de Biologie du Développement de Villefranche-sur-Mer (LBDV), 06230 Villefranche-sur-Mer, France
| | - Alexandre Jan
- Sorbonne Université, CNRS, Institut de la Mer de Villefranche, UMR7009 Laboratoire de Biologie du Développement de Villefranche-sur-Mer (LBDV), 06230 Villefranche-sur-Mer, France
- Sorbonne Université, Institut de la mer de Villefranche, FR3761, Centre de Ressources Biologiques Marines (CRBM), Service Aquariologie, 06230 Villefranche-sur-Mer, France
| | - Axel Duchene
- Sorbonne Université, Institut de la mer de Villefranche, FR3761, Centre de Ressources Biologiques Marines (CRBM), Service Aquariologie, 06230 Villefranche-sur-Mer, France
| | - Julie Uveira
- Sorbonne Université, CNRS, Institut de la Mer de Villefranche, UMR7009 Laboratoire de Biologie du Développement de Villefranche-sur-Mer (LBDV), 06230 Villefranche-sur-Mer, France
| | - Brandon Weissbourd
- California Institute of Technology, Division of Biology and Biological Engineering, and the Howard Hughes Medical Institute, 1200 E California Blvd, Pasadena CA 91125, USA
| | - Loann Gissat
- Sorbonne Université, Institut de la mer de Villefranche, FR3761, Centre de Ressources Biologiques Marines (CRBM), Service Aquariologie, 06230 Villefranche-sur-Mer, France
| | - Sophie Collet
- Sorbonne Université, Institut de la mer de Villefranche, FR3761, Centre de Ressources Biologiques Marines (CRBM), Service Aquariologie, 06230 Villefranche-sur-Mer, France
| | - Laurent Gilletta
- Sorbonne Université, CNRS, Institut de la Mer de Villefranche, UMR7009 Laboratoire de Biologie du Développement de Villefranche-sur-Mer (LBDV), 06230 Villefranche-sur-Mer, France
| | - Sandra Chevalier
- Sorbonne Université, CNRS, Institut de la Mer de Villefranche, UMR7009 Laboratoire de Biologie du Développement de Villefranche-sur-Mer (LBDV), 06230 Villefranche-sur-Mer, France
| | - Lucas Leclère
- Sorbonne Université, CNRS, Institut de la Mer de Villefranche, UMR7009 Laboratoire de Biologie du Développement de Villefranche-sur-Mer (LBDV), 06230 Villefranche-sur-Mer, France
| | - Sophie Peron
- Sorbonne Université, CNRS, Institut de la Mer de Villefranche, UMR7009 Laboratoire de Biologie du Développement de Villefranche-sur-Mer (LBDV), 06230 Villefranche-sur-Mer, France
| | - Carine Barreau
- Sorbonne Université, CNRS, Institut de la Mer de Villefranche, UMR7009 Laboratoire de Biologie du Développement de Villefranche-sur-Mer (LBDV), 06230 Villefranche-sur-Mer, France
| | - Régis Lasbleiz
- Sorbonne Université, Institut de la mer de Villefranche, FR3761, Centre de Ressources Biologiques Marines (CRBM), Service Aquariologie, 06230 Villefranche-sur-Mer, France
| | - Evelyn Houliston
- Sorbonne Université, CNRS, Institut de la Mer de Villefranche, UMR7009 Laboratoire de Biologie du Développement de Villefranche-sur-Mer (LBDV), 06230 Villefranche-sur-Mer, France
| | - Tsuyoshi Momose
- Sorbonne Université, CNRS, Institut de la Mer de Villefranche, UMR7009 Laboratoire de Biologie du Développement de Villefranche-sur-Mer (LBDV), 06230 Villefranche-sur-Mer, France
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12
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Toxin-like neuropeptides in the sea anemone Nematostella unravel recruitment from the nervous system to venom. Proc Natl Acad Sci U S A 2020; 117:27481-27492. [PMID: 33060291 DOI: 10.1073/pnas.2011120117] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The sea anemone Nematostella vectensis (Anthozoa, Cnidaria) is a powerful model for characterizing the evolution of genes functioning in venom and nervous systems. Although venom has evolved independently numerous times in animals, the evolutionary origin of many toxins remains unknown. In this work, we pinpoint an ancestral gene giving rise to a new toxin and functionally characterize both genes in the same species. Thus, we report a case of protein recruitment from the cnidarian nervous to venom system. The ShK-like1 peptide has a ShKT cysteine motif, is lethal for fish larvae and packaged into nematocysts, the cnidarian venom-producing stinging capsules. Thus, ShK-like1 is a toxic venom component. Its paralog, ShK-like2, is a neuropeptide localized to neurons and is involved in development. Both peptides exhibit similarities in their functional activities: They provoke contraction in Nematostella polyps and are toxic to fish. Because ShK-like2 but not ShK-like1 is conserved throughout sea anemone phylogeny, we conclude that the two paralogs originated due to a Nematostella-specific duplication of a ShK-like2 ancestor, a neuropeptide-encoding gene, followed by diversification and partial functional specialization. ShK-like2 is represented by two gene isoforms controlled by alternative promoters conferring regulatory flexibility throughout development. Additionally, we characterized the expression patterns of four other peptides with structural similarities to studied venom components and revealed their unexpected neuronal localization. Thus, we employed genomics, transcriptomics, and functional approaches to reveal one venom component, five neuropeptides with two different cysteine motifs, and an evolutionary pathway from nervous to venom system in Cnidaria.
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13
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A comparative genomics study of neuropeptide genes in the cnidarian subclasses Hexacorallia and Ceriantharia. BMC Genomics 2020; 21:666. [PMID: 32993486 PMCID: PMC7523074 DOI: 10.1186/s12864-020-06945-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 07/24/2020] [Indexed: 12/24/2022] Open
Abstract
Background Nervous systems originated before the split of Proto- and Deuterostomia, more than 600 million years ago. Four animal phyla (Cnidaria, Placozoa, Ctenophora, Porifera) diverged before this split and studying these phyla could give us important information on the evolution of the nervous system. Here, we have annotated the neuropeptide preprohormone genes of twenty species belonging to the subclass Hexacorallia or Ceriantharia (Anthozoa: Cnidaria), using thirty-seven publicly accessible genome or transcriptome databases. Studying hexacorals is important, because they are versatile laboratory models for development (e.g., Nematostella vectensis) and symbiosis (e.g., Exaiptasia diaphana) and also are prominent reef-builders. Results We found that each hexacoral or ceriantharian species contains five to ten neuropeptide preprohormone genes. Many of these preprohormones contain multiple copies of immature neuropeptides, which can be up to 50 copies of identical or similar neuropeptide sequences. We also discovered preprohormones that only contained one neuropeptide sequence positioned directly after the signal sequence. Examples of them are neuropeptides that terminate with the sequence RWamide (the Antho-RWamides). Most neuropeptide sequences are N-terminally protected by pyroglutamyl (pQ) or one or more prolyl residues, while they are C-terminally protected by an amide group. Previously, we isolated and sequenced small neuropeptides from hexacorals that were N-terminally protected by an unusual L-3-phenyllactyl group. In our current analysis, we found that these N-phenyllactyl-peptides are derived from N-phenylalanyl-peptides located directly after the signal sequence of the preprohormone. The N-phenyllactyl- peptides appear to be confined to the hexacorallian order Actiniaria and do not occur in other cnidarians. On the other hand, (1) the neuropeptide Antho-RFamide (pQGRFamide); (2) peptides with the C-terminal sequence GLWamide; and (3) tetrapeptides with the X1PRX2amide consensus sequence (most frequently GPRGamide) are ubiquitous in Hexacorallia. Conclusions We found GRFamide, GLWamide, and X1PRX2amide peptides in all tested Hexacorallia. Previously, we discovered these three neuropeptide classes also in Cubozoa, Scyphozoa, and Staurozoa, indicating that these neuropeptides originated in the common cnidarian ancestor and are evolutionarily ancient. In addition to these ubiquitous neuropeptides, other neuropeptides appear to be confined to specific cnidarian orders or subclasses.
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14
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Shikina S, Chiu YL, Zhang Y, Yi-ChenYao, Liu TY, Tsai PH, Zatylny-Gaudin C, Chang CF. Involvement of GLWamide neuropeptides in polyp contraction of the adult stony coral Euphyllia ancora. Sci Rep 2020; 10:9427. [PMID: 32523083 PMCID: PMC7287070 DOI: 10.1038/s41598-020-66438-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 05/12/2020] [Indexed: 12/15/2022] Open
Abstract
The existence and function of neurons remain largely unexplored in scleractinian corals. To gain a better understanding of neuronal functions in coral physiology, this study focused on Glycine-Leucine-Tryptophan-amide family neuropeptides (GLWamides), which have been shown to induce muscle contraction and larval metamorphosis in other cnidarians. Molecular identification and functional characterization of GLWamides in the adult stony coral Euphyllia ancora were performed. We successfully elucidated the full-length cDNA of GLWamide preprohormone in E. ancora (named EaGLW preprohormone). The deduced amino acid sequence was predicted to contain six potential GLWamide peptides. Tissue distribution analysis demonstrated that transcripts of EaGLW preprohormone were mainly expressed in the mouth (including the pharynx) and tentacles of the polyps. Immunodetection with an anti-GLWamide monoclonal antibody revealed that GLWamide neurons were mainly distributed in the epidermis of the mouth region and tentacle, in agreement with the distribution patterns of the transcripts. Treatment of the isolated mouth and tentacles with synthetic GLWamide peptides induced the contraction of these isolated tissues. Treatment of polyps with synthetic GLWamide peptides induced the contraction of polyps. These results suggest that GLWamides are involved in polyp contraction (myoactivity) in adult scleractinians. Our data provide new information on the physiological function of neuropeptides in scleractinians.
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Affiliation(s)
- Shinya Shikina
- Institute of Marine Environment and Ecology, National Taiwan Ocean University, Keelung, 20224, Taiwan. .,Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung, 20224, Taiwan.
| | - Yi-Ling Chiu
- Doctoral degree Program in Marine Biotechnology, National Taiwan Ocean University, Keelung, Taiwan.,Doctoral degree Program in Marine Biotechnology, Academia Sinica, Taipei, Taiwan
| | - Yan Zhang
- Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung, 20224, Taiwan.,Department of Aquaculture, National Taiwan Ocean University, Keelung, Taiwan
| | - Yi-ChenYao
- Department of Aquaculture, National Taiwan Ocean University, Keelung, Taiwan
| | - Tai-Yu Liu
- Department of Aquaculture, National Taiwan Ocean University, Keelung, Taiwan
| | - Pin-Hsuan Tsai
- Institute of Marine Environment and Ecology, National Taiwan Ocean University, Keelung, 20224, Taiwan
| | | | - Ching-Fong Chang
- Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung, 20224, Taiwan. .,Department of Aquaculture, National Taiwan Ocean University, Keelung, Taiwan.
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15
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A G protein-coupled receptor mediates neuropeptide-induced oocyte maturation in the jellyfish Clytia. PLoS Biol 2020; 18:e3000614. [PMID: 32126082 PMCID: PMC7053711 DOI: 10.1371/journal.pbio.3000614] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 01/28/2020] [Indexed: 12/12/2022] Open
Abstract
The reproductive hormones that trigger oocyte meiotic maturation and release from the ovary vary greatly between animal species. Identification of receptors for these maturation-inducing hormones (MIHs) and understanding how they initiate the largely conserved maturation process remain important challenges. In hydrozoan cnidarians including the jellyfish Clytia hemisphaerica, MIH comprises neuropeptides released from somatic cells of the gonad. We identified the receptor (MIHR) for these MIH neuropeptides in Clytia using cell culture–based “deorphanization” of candidate oocyte-expressed G protein–coupled receptors (GPCRs). MIHR mutant jellyfish generated using CRISPR-Cas9 editing had severe defects in gamete development or in spawning both in males and females. Female gonads, or oocytes isolated from MIHR mutants, failed to respond to synthetic MIH. Treatment with the cAMP analogue Br-cAMP to mimic cAMP rise at maturation onset rescued meiotic maturation and spawning. Injection of inhibitory antibodies to the alpha subunit of the Gs heterodimeric protein (GαS) into wild-type oocytes phenocopied the MIHR mutants. These results provide the molecular links between MIH stimulation and meiotic maturation initiation in hydrozoan oocytes. Molecular phylogeny grouped Clytia MIHR with a subset of bilaterian neuropeptide receptors, including neuropeptide Y, gonadotropin inhibitory hormone (GnIH), pyroglutamylated RFamide, and luqin, all upstream regulators of sexual reproduction. This identification and functional characterization of a cnidarian peptide GPCR advances our understanding of oocyte maturation initiation and sheds light on the evolution of neuropeptide-hormone systems. A study of jellyfish oocytes identifies the receptor for Maturation-Inducing Hormone, the neuropeptide hormone that triggers oocyte maturation and spawning via GαS and cyclic AMP. This receptor defines a superfamily of hormone-receptor systems involved in regulating sexual reproduction across animal species.
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16
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Buzgariu W, Curchod ML, Perruchoud C, Galliot B. Combining BrdU-Labeling to Detection of Neuronal Markers to Monitor Adult Neurogenesis in Hydra. Methods Mol Biol 2020; 2047:3-24. [PMID: 31552646 DOI: 10.1007/978-1-4939-9732-9_1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The nervous system is produced and maintained in adult Hydra through the continuous production of nerve cells and mechanosensory cells (nematocytes or cnidocytes). De novo neurogenesis occurs slowly in intact animals that replace their dying nerve cells, at a faster rate in animals regenerating their head as a complete apical nervous system is built in few days. To dissect the molecular mechanisms that underlie these properties, a precise monitoring of the markers of neurogenesis and nematogenesis is required. Here we describe the conditions for an efficient BrdU-labeling coupled to an immunodetection of neuronal markers, either regulators of neurogenesis, here the homeoprotein prdl-a, or neuropeptides such as RFamide or Hym-355. This method can be performed on whole-mount animals as well as on macerated tissues when cells retain their morphology. Moreover, when antibodies are not available, BrdU-labeling can be combined with the analysis of gene expression by whole-mount in situ hybridization. This co-immunodetection procedure is well adapted to visualize and quantify the dynamics of de novo neurogenesis. Upon continuous BrdU labeling, the repeated measurements of BrdU-labeling indexes in specific cellular populations provide a precise monitoring of nematogenesis as well as neurogenesis, in homeostatic or developmental conditions.
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Affiliation(s)
- Wanda Buzgariu
- Department of Genetics and Evolution, iGE3, Faculty of Sciences, University of Geneva, Geneva, Switzerland
| | - Marie-Laure Curchod
- Department of Genetics and Evolution, iGE3, Faculty of Sciences, University of Geneva, Geneva, Switzerland
| | - Chrystelle Perruchoud
- Department of Genetics and Evolution, iGE3, Faculty of Sciences, University of Geneva, Geneva, Switzerland
| | - Brigitte Galliot
- Department of Genetics and Evolution, iGE3, Faculty of Sciences, University of Geneva, Geneva, Switzerland.
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17
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Arnellos A, Keijzer F. Bodily Complexity: Integrated Multicellular Organizations for Contraction-Based Motility. Front Physiol 2019; 10:1268. [PMID: 31680996 PMCID: PMC6803425 DOI: 10.3389/fphys.2019.01268] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Accepted: 09/19/2019] [Indexed: 01/13/2023] Open
Abstract
Compared to other forms of multicellularity, the animal case is unique. Animals-barring some exceptions-consist of collections of cells that are connected and integrated to such an extent that these collectives act as unitary, large free-moving entities capable of sensing macroscopic properties and events. This animal configuration is so well-known that it is often taken as a natural one that 'must' have evolved, given environmental conditions that make large free-moving units 'obviously' adaptive. Here we question the seemingly evolutionary inevitableness of animals and introduce a thesis of bodily complexity: The multicellular organization characteristic for typical animals requires the integration of a multitude of intrinsic bodily features between its sensorimotor, physiological, and developmental aspects, and the related contraction-based tissue- and cellular-level events and processes. The evolutionary road toward this bodily complexity involves, we argue, various intermediate organizational steps that accompany and support the wider transition from cilia-based to contraction/muscle-based motility, and which remain insufficiently acknowledged. Here, we stress the crucial and specific role played by muscle-based and myoepithelial tissue contraction-acting as a physical platform for organizing both the multicellular transmission of mechanical forces and multicellular signaling-as key foundation of animal motility, sensing and maintenance, and development. We illustrate and discuss these bodily features in the context of the four basal animal phyla-Porifera, Ctenophores, Placozoans, and Cnidarians-that split off before the bilaterians, a supergroup that incorporates all complex animals.
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Affiliation(s)
- Argyris Arnellos
- IAS-Research Centre for Life, Mind & Society, Department of Logic and Philosophy of Science, University of the Basque Country, San Sebastián, Spain.,Department of Product and Systems Design Engineering, Complex Systems and Service Design Lab, University of the Aegean, Syros, Greece
| | - Fred Keijzer
- Department of Theoretical Philosophy, University of Groningen, Groningen, Netherlands
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18
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Nielsen SKD, Koch TL, Hauser F, Garm A, Grimmelikhuijzen CJP. De novo transcriptome assembly of the cubomedusa Tripedalia cystophora, including the analysis of a set of genes involved in peptidergic neurotransmission. BMC Genomics 2019; 20:175. [PMID: 30836949 PMCID: PMC6402141 DOI: 10.1186/s12864-019-5514-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 02/07/2019] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND The phyla Cnidaria, Placozoa, Ctenophora, and Porifera emerged before the split of proto- and deuterostome animals, about 600 million years ago. These early metazoans are interesting, because they can give us important information on the evolution of various tissues and organs, such as eyes and the nervous system. Generally, cnidarians have simple nervous systems, which use neuropeptides for their neurotransmission, but some cnidarian medusae belonging to the class Cubozoa (box jellyfishes) have advanced image-forming eyes, probably associated with a complex innervation. Here, we describe a new transcriptome database from the cubomedusa Tripedalia cystophora. RESULTS Based on the combined use of the Illumina and PacBio sequencing technologies, we produced a highly contiguous transcriptome database from T. cystophora. We then developed a software program to discover neuropeptide preprohormones in this database. This script enabled us to annotate seven novel T. cystophora neuropeptide preprohormone cDNAs: One coding for 19 copies of a peptide with the structure pQWLRGRFamide; one coding for six copies of a different RFamide peptide; one coding for six copies of pQPPGVWamide; one coding for eight different neuropeptide copies with the C-terminal LWamide sequence; one coding for thirteen copies of a peptide with the RPRAamide C-terminus; one coding for four copies of a peptide with the C-terminal GRYamide sequence; and one coding for seven copies of a cyclic peptide, of which the most frequent one has the sequence CTGQMCWFRamide. We could also identify orthologs of these seven preprohormones in the cubozoans Alatina alata, Carybdea xaymacana, Chironex fleckeri, and Chiropsalmus quadrumanus. Furthermore, using TBLASTN screening, we could annotate four bursicon-like glycoprotein hormone subunits, five opsins, and 52 other family-A G protein-coupled receptors (GPCRs), which also included two leucine-rich repeats containing G protein-coupled receptors (LGRs) in T. cystophora. The two LGRs are potential receptors for the glycoprotein hormones, while the other GPCRs are candidate receptors for the above-mentioned neuropeptides. CONCLUSIONS By combining Illumina and PacBio sequencing technologies, we have produced a new high-quality de novo transcriptome assembly from T. cystophora that should be a valuable resource for identifying the neuronal components that are involved in vision and other behaviors in cubomedusae.
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Affiliation(s)
- Sofie K. D. Nielsen
- Section of Marine Biology, Department of Biology, University of Copenhagen, Universitetsparken 4, 2100 Copenhagen, Denmark
| | - Thomas L. Koch
- Section for Cell and Neurobiology, Department of Biology, University of Copenhagen, Universitetsparken 15, DK-2100 Copenhagen, Denmark
| | - Frank Hauser
- Section for Cell and Neurobiology, Department of Biology, University of Copenhagen, Universitetsparken 15, DK-2100 Copenhagen, Denmark
| | - Anders Garm
- Section of Marine Biology, Department of Biology, University of Copenhagen, Universitetsparken 4, 2100 Copenhagen, Denmark
| | - Cornelis J. P. Grimmelikhuijzen
- Section for Cell and Neurobiology, Department of Biology, University of Copenhagen, Universitetsparken 15, DK-2100 Copenhagen, Denmark
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Zheng Z, Hao R, Xiong X, Jiao Y, Deng Y, Du X. Developmental characteristics of pearl oyster Pinctada fucata martensii: insight into key molecular events related to shell formation, settlement and metamorphosis. BMC Genomics 2019; 20:122. [PMID: 30736747 PMCID: PMC6368781 DOI: 10.1186/s12864-019-5505-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 02/01/2019] [Indexed: 01/08/2023] Open
Abstract
Background Marine bivalves undergo complex development processes, such as shell morphology conversion and changes of anatomy and life habits. In this study, the transcriptomes of pearl oyster Pinctada fucata martensii and Pacific oyster Crassostrea gigas at different development stages were analyzed to determine the key molecular events related to shell formation, settlement and metamorphosis. Result According to the shell matrix proteome, biomineralization-related genes exhibited a consensus expression model with the critical stages of shell formation. Differential expression analysis of P. f. martensii, revealed the negative regulation and feedback of extracellular matrixs as well as growth factor pathways involved in shell formation of larvae, similar to that in C. gigas. Furthermore, neuroendocrine pathways in hormone receptors, neurotransmitters and neuropeptide receptors were involved in shell formation, settlement and metamorphosis. Conclusion Our research demonstrated the main clusters of regulation elements related to shell formation, settlement and metamorphosis. The regulation of shell formation and metamorphosis could be coupled forming the neuroendocrine-biomineralization crosstalk in metamorphosis. These findings could provide new insights into the regulation in bivalve development. Electronic supplementary material The online version of this article (10.1186/s12864-019-5505-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Zhe Zheng
- Fishery College, Guangdong Ocean University, Zhanjiang, 524088, China.,Pearl Breeding and Processing Engineering Technology Research Center of Guangdong Province, Zhanjiang, 524088, China
| | - Ruijuan Hao
- Fishery College, Guangdong Ocean University, Zhanjiang, 524088, China.,Pearl Breeding and Processing Engineering Technology Research Center of Guangdong Province, Zhanjiang, 524088, China
| | - Xinwei Xiong
- Fishery College, Guangdong Ocean University, Zhanjiang, 524088, China.,Pearl Breeding and Processing Engineering Technology Research Center of Guangdong Province, Zhanjiang, 524088, China
| | - Yu Jiao
- Fishery College, Guangdong Ocean University, Zhanjiang, 524088, China.,Pearl Breeding and Processing Engineering Technology Research Center of Guangdong Province, Zhanjiang, 524088, China
| | - Yuewen Deng
- Fishery College, Guangdong Ocean University, Zhanjiang, 524088, China. .,Pearl Breeding and Processing Engineering Technology Research Center of Guangdong Province, Zhanjiang, 524088, China.
| | - Xiaodong Du
- Fishery College, Guangdong Ocean University, Zhanjiang, 524088, China. .,Pearl Breeding and Processing Engineering Technology Research Center of Guangdong Province, Zhanjiang, 524088, China.
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20
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Attenborough RM, Hayward DC, Wiedemann U, Forêt S, Miller DJ, Ball EE. Expression of the neuropeptides RFamide and LWamide during development of the coral Acropora millepora in relation to settlement and metamorphosis. Dev Biol 2019; 446:56-67. [DOI: 10.1016/j.ydbio.2018.11.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 11/22/2018] [Accepted: 11/30/2018] [Indexed: 10/27/2022]
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21
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Rentzsch F, Juliano C, Galliot B. Modern genomic tools reveal the structural and cellular diversity of cnidarian nervous systems. Curr Opin Neurobiol 2019; 56:87-96. [PMID: 30654234 DOI: 10.1016/j.conb.2018.12.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 12/10/2018] [Accepted: 12/11/2018] [Indexed: 12/11/2022]
Abstract
Cnidarians shared a common ancestor with bilaterians more than 600 million years ago. This sister group relationship gives them an informative phylogenetic position for understanding the fascinating morphological and molecular cell type diversity of bilaterian nervous systems. Moreover, cnidarians display novel features such as endodermal neurogenesis and independently evolved centralizations, which provide a platform for understanding the evolution of nervous system innovations. In recent years, the application of modern genomic tools has significantly advanced our understanding of cnidarian nervous system structure and function. For example, transgenic reporter lines and gene knockdown experiments in several cnidarian species reveal a significant degree of conservation in the neurogenesis gene regulatory program, while single cell RNA sequencing projects are providing a much deeper understanding of cnidarian neural cell type diversity. At the level of neural function, the physiological properties of ion channels have been described and calcium imaging of the nervous system in whole animals has allowed for the identification of neural circuits underlying specific behaviours. Cnidarians have arrived in the modern era of molecular neurobiology and are primed to provide exciting new insights into the early evolution of nervous systems.
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Affiliation(s)
- Fabian Rentzsch
- Sars Centre for Marine Molecular Biology, Norway; Department for Biological Sciences, University of Bergen, Norway.
| | - Celina Juliano
- Department of Molecular and Cellular Biology, University of California Davis, CA 95616, United States.
| | - Brigitte Galliot
- Department of Genetics and Evolution, Institute of Genetics and Genomics in Geneva (iGE3), University of Geneva, Switzerland.
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Koch TL, Grimmelikhuijzen CJP. Global Neuropeptide Annotations From the Genomes and Transcriptomes of Cubozoa, Scyphozoa, Staurozoa (Cnidaria: Medusozoa), and Octocorallia (Cnidaria: Anthozoa). Front Endocrinol (Lausanne) 2019; 10:831. [PMID: 31866941 PMCID: PMC6909153 DOI: 10.3389/fendo.2019.00831] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 11/13/2019] [Indexed: 12/05/2022] Open
Abstract
During animal evolution, ancestral Cnidaria and Bilateria diverged more than 600 million years ago. The nervous systems of extant cnidarians are strongly peptidergic. Neuropeptides have been isolated and sequenced from a few model cnidarians, but a global investigation of the presence of neuropeptides in all cnidarian classes has been lacking. Here, we have used a recently developed software program to annotate neuropeptides in the publicly available genomes and transcriptomes from members of the classes Cubozoa, Scyphozoa, and Staurozoa (which all belong to the subphylum Medusozoa) and contrasted these results with neuropeptides present in the subclass Octocorallia (belonging to the class Anthozoa). We found three to six neuropeptide preprohormone genes in members of the above-mentioned cnidarian classes or subclasses, each coding for several (up to thirty-two) similar or identical neuropeptide copies. Two of these neuropeptide preprohormone genes are present in all cnidarian classes/subclasses investigated, so they are good candidates for being among the first neuropeptide genes evolved in cnidarians. One of these primordial neuropeptide genes codes for neuropeptides having the C-terminal sequence GRFamide (pQGRFamide in Octocorallia; pQWLRGRFamide in Cubozoa and Scyphozoa; pQFLRGRFamide in Staurozoa). The other primordial neuropeptide gene codes for peptides having RPRSamide or closely resembling amino acid sequences. In addition to these two primordial neuropeptide sequences, cnidarians have their own class- or subclass-specific neuropeptides, which probably evolved to serve class/subclass-specific needs. When we carried out phylogenetic tree analyses of the GRFamide or RPRSamide preprohormones from cubozoans, scyphozoans, staurozoans, and octocorallia, we found that their phylogenetic relationships perfectly agreed with current models of the phylogeny of the studied cnidarian classes and subclasses. These results support the early origins of the GRFamide and RPRSamide preprohormone genes.
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Oliveira CS, Caldeira CAS, Diniz-Sousa R, Romero DL, Marcussi S, Moura LA, Fuly AL, de Carvalho C, Cavalcante WLG, Gallacci M, Pai MD, Zuliani JP, Calderon LA, Soares AM. Pharmacological characterization of cnidarian extracts from the Caribbean Sea: evaluation of anti-snake venom and antitumor properties. J Venom Anim Toxins Incl Trop Dis 2018; 24:22. [PMID: 30181737 PMCID: PMC6114500 DOI: 10.1186/s40409-018-0161-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 08/07/2018] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Cnidarians produce toxins, which are composed of different polypeptides that induce pharmacological effects of biotechnological interest, such as antitumor, antiophidic and anti-clotting activities. This study aimed to evaluate toxicological activities and potential as antitumor and antiophidic agents contained in total extracts from five cnidarians: Millepora alcicornis, Stichodactyla helianthus, Plexaura homomalla, Bartholomea annulata and Condylactis gigantea (total and body wall). METHODS The cnidarian extracts were evaluated by electrophoresis and for their phospholipase, proteolytic, hemorrhagic, coagulant, fibrinogenolytic, neuromuscular blocking, muscle-damaging, edema-inducing and cytotoxic activities. RESULTS All cnidarian extracts showed indirect hemolytic activity, but only S. helianthus induced direct hemolysis and neurotoxic effect. However, the hydrolysis of NBD-PC, a PLA2 substrate, was presented only by the C. gigantea (body wall) and S. helianthus. The extracts from P. homomalla and S. helianthus induced edema, while only C. gigantea and S. helianthus showed intensified myotoxic activity. The proteolytic activity upon casein and fibrinogen was presented mainly by B. annulata extract and all were unable to induce hemorrhage or fibrinogen coagulation. Cnidarian extracts were able to neutralize clotting induced by Bothrops jararacussu snake venom, except M. alcicornis. All cnidarian extracts were able to inhibit hemorrhagic activity induced by Bothrops moojeni venom. Only the C. gigantea (body wall) inhibited thrombin-induced coagulation. All cnidarian extracts showed antitumor effect against Jurkat cells, of which C. gigantea (body wall) and S. helianthus were the most active; however, only C. gigantea (body wall) and M. alcicornis were active against B16F10 cells. CONCLUSION The cnidarian extracts analyzed showed relevant in vitro inhibitory potential over the activities induced by Bothrops venoms; these results may contribute to elucidate the possible mechanisms of interaction between cnidarian extracts and snake venoms.
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Affiliation(s)
- Cláudia S. Oliveira
- Centro de Estudos de Biomoléculas Aplicadas a Saúde (CEBio), Fundação Oswaldo Cruz de Rondônia (Fiocruz Rondônia), Porto Velho, RO Brazil
- Brazilian Marine Biotechnology Network (BioTecMar Network), Porto Velho, Brazil
- Departamento de Medicina, Universidade Federal de Rondônia (UNIR), Porto Velho, RO Brazil
| | - Cleópatra A. S. Caldeira
- Centro de Estudos de Biomoléculas Aplicadas a Saúde (CEBio), Fundação Oswaldo Cruz de Rondônia (Fiocruz Rondônia), Porto Velho, RO Brazil
- Brazilian Marine Biotechnology Network (BioTecMar Network), Porto Velho, Brazil
- Departamento de Medicina, Universidade Federal de Rondônia (UNIR), Porto Velho, RO Brazil
| | - Rafaela Diniz-Sousa
- Centro de Estudos de Biomoléculas Aplicadas a Saúde (CEBio), Fundação Oswaldo Cruz de Rondônia (Fiocruz Rondônia), Porto Velho, RO Brazil
- Brazilian Marine Biotechnology Network (BioTecMar Network), Porto Velho, Brazil
- Departamento de Medicina, Universidade Federal de Rondônia (UNIR), Porto Velho, RO Brazil
| | - Dolores L. Romero
- Centro de Estudios de Proteínas, Facultad de Biología, Universidad de La Habana, Havana, Cuba
| | - Silvana Marcussi
- Departamento de Química, Universidade Federal de Lavras (UFLA), Lavras, MG Brazil
| | - Laura A. Moura
- Departamento de Biologia Celular e Molecular (GCM), Instituto de Biologia, Universidade Federal Fluminense (UFF), Niterói, RJ Brazil
| | - André L. Fuly
- Departamento de Biologia Celular e Molecular (GCM), Instituto de Biologia, Universidade Federal Fluminense (UFF), Niterói, RJ Brazil
| | - Cicília de Carvalho
- Departamento de Farmacologia, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, SP Brazil
| | - Walter L. G. Cavalcante
- Departamento de Farmacologia, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, SP Brazil
- Instituto de Ciências Biológicas, Departamento de Farmacologia, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG Brazil
| | - Márcia Gallacci
- Departamento de Farmacologia, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, SP Brazil
| | - Maeli Dal Pai
- Departamento de Morfologia, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, SP Brazil
| | - Juliana P. Zuliani
- Centro de Estudos de Biomoléculas Aplicadas a Saúde (CEBio), Fundação Oswaldo Cruz de Rondônia (Fiocruz Rondônia), Porto Velho, RO Brazil
- Brazilian Marine Biotechnology Network (BioTecMar Network), Porto Velho, Brazil
- Departamento de Medicina, Universidade Federal de Rondônia (UNIR), Porto Velho, RO Brazil
| | - Leonardo A. Calderon
- Centro de Estudos de Biomoléculas Aplicadas a Saúde (CEBio), Fundação Oswaldo Cruz de Rondônia (Fiocruz Rondônia), Porto Velho, RO Brazil
- Brazilian Marine Biotechnology Network (BioTecMar Network), Porto Velho, Brazil
- Departamento de Medicina, Universidade Federal de Rondônia (UNIR), Porto Velho, RO Brazil
| | - Andreimar M. Soares
- Centro de Estudos de Biomoléculas Aplicadas a Saúde (CEBio), Fundação Oswaldo Cruz de Rondônia (Fiocruz Rondônia), Porto Velho, RO Brazil
- Brazilian Marine Biotechnology Network (BioTecMar Network), Porto Velho, Brazil
- Departamento de Medicina, Universidade Federal de Rondônia (UNIR), Porto Velho, RO Brazil
- Centro Universitário São Lucas (UniSL), Porto Velho, RO Brazil
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Senatore A, Reese TS, Smith CL. Neuropeptidergic integration of behavior in Trichoplax adhaerens, an animal without synapses. J Exp Biol 2017; 220:3381-3390. [PMID: 28931721 PMCID: PMC5612019 DOI: 10.1242/jeb.162396] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 07/04/2017] [Indexed: 12/17/2022]
Abstract
Trichoplax adhaerens is a flat, millimeter-sized marine animal that adheres to surfaces and grazes on algae. Trichoplax displays a repertoire of different feeding behaviors despite the apparent absence of a true nervous system with electrical or chemical synapses. It glides along surfaces to find food, propelled by beating cilia on cells at its ventral surface, and pauses during feeding by arresting ciliary beating. We found that when endomorphin-like peptides are applied to an animal, ciliary beating is arrested, mimicking natural feeding pauses. Antibodies against these neuropeptides label cells that express the neurosecretory proteins and voltage-gated calcium channels implicated in regulated secretion. These cells are embedded in the ventral epithelium, where they comprise only 4% of the total, and are concentrated around the edge of the animal. Each bears a cilium likely to be chemosensory and used to detect algae. Trichoplax pausing during feeding or spontaneously in the absence of food often induce their neighbors to pause as well, even neighbors not in direct contact. Pausing behavior propagates from animal to animal across distances much greater than the signal that diffuses from just one animal, so we presume that the peptides secreted from one animal elicit secretion from nearby animals. Signal amplification by peptide-induced peptide secretion explains how a small number of sensory secretory cells lacking processes and synapses can evoke a wave of peptide secretion across the entire animal to globally arrest ciliary beating and allow pausing during feeding.
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Affiliation(s)
- Adriano Senatore
- University of Toronto Mississauga, Mississauga, ON, Canada L5L 1C6
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Schoofs L, De Loof A, Van Hiel MB. Neuropeptides as Regulators of Behavior in Insects. ANNUAL REVIEW OF ENTOMOLOGY 2017; 62:35-52. [PMID: 27813667 DOI: 10.1146/annurev-ento-031616-035500] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Neuropeptides are by far the largest and most diverse group of signaling molecules in multicellular organisms. They are ancient molecules important in regulating a multitude of processes. Their small proteinaceous character allowed them to evolve and radiate quickly into numerous different molecules. On average, hundreds of distinct neuropeptides are present in animals, sometimes with unique classes that do not occur in distantly related species. Acting as neurotransmitters, neuromodulators, hormones, or growth factors, they are extremely diverse and are involved in controlling growth, development, ecdysis, digestion, diuresis, and many more physiological processes. Neuropeptides are also crucial in regulating myriad behavioral actions associated with feeding, courtship, sleep, learning and memory, stress, addiction, and social interactions. In general, behavior ensures that an organism can survive in its environment and is defined as any action that can change an organism's relationship to its surroundings. Even though the mode of action of neuropeptides in insects has been vigorously studied, relatively little is known about most neuropeptides and only a few model insects have been investigated. Here, we provide an overview of the roles neuropeptides play in insect behavior. We conclude that multiple neuropeptides need to work in concert to coordinate certain behaviors. Additionally, most neuropeptides studied to date have more than a single function.
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Affiliation(s)
- Liliane Schoofs
- Functional Genomics and Proteomics Group, Department of Biology, KU Leuven, 3000 Leuven, Belgium; , ,
| | - Arnold De Loof
- Functional Genomics and Proteomics Group, Department of Biology, KU Leuven, 3000 Leuven, Belgium; , ,
| | - Matthias Boris Van Hiel
- Functional Genomics and Proteomics Group, Department of Biology, KU Leuven, 3000 Leuven, Belgium; , ,
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De Loof A, Schoofs L, Huybrechts R. The endocrine system controlling sexual reproduction in animals: Part of the evolutionary ancient but well conserved immune system? Gen Comp Endocrinol 2016; 226:56-71. [PMID: 26707056 DOI: 10.1016/j.ygcen.2015.12.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 12/08/2015] [Accepted: 12/15/2015] [Indexed: 12/14/2022]
Abstract
Drastic changes in hormone titers, in particular of steroid hormones, are intuitively interpreted as necessary and beneficial for optimal functioning of animals. Peaks in progesterone- and estradiol titers that accompany the estrus cycle in female vertebrates as well as in ecdysteroids at each molt and during metamorphosis of holometabolous insects are prominent examples. A recent analysis of insect metamorphosis yielded the view that, in general, a sharp rise in sex steroid hormone titer signals that somewhere in the body some tissue(s) is undergoing programmed cell death/apoptosis. Increased steroid production is part of this process. Typical examples are ovarian follicle cells in female vertebrates and invertebrates and the prothoracic gland cells, the main production site of ecdysteroids in larval insects. A duality emerges: programmed cell death-apoptosis is deleterious at the cellular level, but it may yield beneficial effects at the organismal level. Reconciling both opposites requires reevaluating the probable evolutionary origin and role of peptidic brain hormones that direct steroid hormone synthesis. Do e.g. Luteinizing Hormone in vertebrates and Prothoracicotropic Hormone (PTTH: acting through the Torso receptor) in insects still retain an ancient role as toxins in the early immune system? Does the functional link of some neuropeptides with Ca(2+)-induced apoptosis make sense in endocrine archeology? The endocrine system as a remnant of the ancient immune system is undoubtedly counterintuitive. Yet, we will argue that such paradigm enables the logical framing of many aspects, the endocrine one inclusive of both male and female reproductive physiology.
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Affiliation(s)
- Arnold De Loof
- Functional Genomics and Proteomics Group, Department of Biology, KU Leuven-University of Leuven, Belgium.
| | - Liliane Schoofs
- Functional Genomics and Proteomics Group, Department of Biology, KU Leuven-University of Leuven, Belgium
| | - Roger Huybrechts
- Insect Physiology and Molecular Ethology Group, Department of Biology, KU Leuven-University of Leuven, Belgium
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