1
|
Zhao M, Mussini G, Li Y, Tang F, Vickers-Rich P, Li M, Chen A. A putative triradial macrofossil from the Ediacaran Jiangchuan Biota. iScience 2024; 27:108823. [PMID: 38303714 PMCID: PMC10831930 DOI: 10.1016/j.isci.2024.108823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 09/28/2023] [Accepted: 01/02/2024] [Indexed: 02/03/2024] Open
Abstract
The late Ediacaran Jiangchuan biota, from the Dengying Formation in eastern Yunnan, is well-known for its diverse macroalgal fossils, opening a window onto eukaryotic-dominated ecosystems from the late Neoproterozoic of South China. Although multiple lines of evidence suggest that metazoans had already evolved by the late Ediacaran, animal fossils have not yet been formally described from this locality. Here, we report a putative disc-shaped macrofossil from the Jiangchuan biota, Lobodiscus tribrachialis gen. et sp. nov. This specimen shows the triradial symmetry characteristic of trilobozoans, a group of Ediacaran macrofossils previously documented in Australia and Russia. Lobodiscus could record the youngest known occurrence of trilobozoans, strengthening taxonomic and ecological continuities between the Ediacaran "White Sea" and "Nama" assemblages. Our findings may expand the known paleogeographical distribution of trilobozoans and provide data for Ediacaran biostratigraphic correlations across the Yangtze block and globally, helping to track the diversification of early metazoan-grade organisms.
Collapse
Affiliation(s)
- Mingsheng Zhao
- College of Paleontology, Shenyang Normal University, Shenyang 110034, China
| | - Giovanni Mussini
- Department of Earth Sciences, University of Cambridge, Cambridge CB2 3EQ, UK
| | - Yulan Li
- 111 Geological Brigade, Guizhou Bureau of Geology and Mineral Resources, Guiyang 550081, China
| | - Feng Tang
- Key Laboratory for Stratigraphy and Palaeontology, MNRC, Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China
| | - Patricia Vickers-Rich
- School of Earth, Atmosphere and Environment, Monash University, Melbourne, VIC 3800, Australia
- Department of Chemistry, Chemistry and Resources precinct, Curtin University, Perth, WA 6845, Australia
| | - Ming Li
- Key Laboratory for Stratigraphy and Palaeontology, MNRC, Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China
| | - Ailin Chen
- Research Center of Paleobiology, Yuxi Normal University, Yuxi 653100, China
| |
Collapse
|
2
|
Romanova DY, Varoqueaux F, Eitel M, Yoshida MA, Nikitin MA, Moroz LL. Long-Term Culturing of Placozoans (Trichoplax and Hoilungia). Methods Mol Biol 2024; 2757:509-529. [PMID: 38668981 DOI: 10.1007/978-1-0716-3642-8_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2024]
Abstract
The phylum Placozoa remains one of the least explored among early-branching metazoan lineages. For over 130 years, this phylum had been represented by the single species Trichoplax adhaerens-an animal with the simplest known body plan (three cell layers without any organs) but complex behaviors. Recently, extensive sampling of placozoans across the globe and their subsequent genetic analysis have revealed incredible biodiversity with numerous cryptic species worldwide. However, only a few culture protocols are available to date, and all are for one species only. Here, we describe the breeding of four different species representing two placozoan genera: Trichoplax adhaerens, Trichoplax sp. H2, Hoilungia sp. H4, and Hoilungia hongkongensis originating from diverse biotopes. Our protocols allow to culture all species under comparable conditions. Next, we outlined various food sources and optimized strain-specific parameters enabling long-term culturing. These protocols can facilitate comparative analyses of placozoan biology and behaviors, which together will contribute to deciphering general principles of animal organization.
Collapse
Affiliation(s)
- Daria Y Romanova
- Institute of Higher Nervous Activity and Neurophysiology of RAS, Moscow, Russia.
| | - Frédérique Varoqueaux
- Department of Fundamental Neurosciences, University of Lausanne, Lausanne, Switzerland.
| | - Michael Eitel
- Department of Earth and Environmental Sciences Palaeontology & Geobiology, LMU München, Munich, Germany
| | - Masa-Aki Yoshida
- Marine Biological Science Section, Education and Research Center for Biological Resources, Faculty of Life and Environmental Science, Shimane University, Okinoshima, Oki, Shimane, Japan
| | - Mikhail A Nikitin
- Institute of Higher Nervous Activity and Neurophysiology of RAS, Moscow, Russia
- Belozersky Institute for Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
- Kharkevich Institute for Information Transmission Problems, RAS, Moscow, Russia
| | - Leonid L Moroz
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL, USA.
- Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL, USA.
| |
Collapse
|
3
|
Romanova DY, Moroz LL. Brief History of Placozoa. Methods Mol Biol 2024; 2757:103-122. [PMID: 38668963 DOI: 10.1007/978-1-0716-3642-8_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2024]
Abstract
Placozoans are morphologically the simplest free-living animals. They represent a unique window of opportunities to understand both the origin of the animal organization and the rules of life for the system and synthetic biology of the future. However, despite more than 100 years of their investigations, we know little about their organization, natural habitats, and life strategies. Here, we introduce this unique animal phylum and highlight some directions vital to broadening the frontiers of the biomedical sciences. In particular, understanding the genomic bases of placozoan biodiversity, cell identity, connectivity, reproduction, and cellular bases of behavior are critical hot spots for future studies.
Collapse
Affiliation(s)
- Daria Y Romanova
- Institute of Higher Nervous Activity and Neurophysiology of RAS, Moscow, Russian Federation.
| | - Leonid L Moroz
- Department of Neuroscience and McKnight Brain Institute, University of Florida, Gainesville, FL, USA.
- Whitney Laboratory for Marine Biosciences University of Florida, St. Augustine, FL, USA.
| |
Collapse
|
4
|
Bondoc-Naumovitz KG, Laeverenz-Schlogelhofer H, Poon RN, Boggon AK, Bentley SA, Cortese D, Wan KY. Methods and Measures for Investigating Microscale Motility. Integr Comp Biol 2023; 63:1485-1508. [PMID: 37336589 PMCID: PMC10755196 DOI: 10.1093/icb/icad075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 05/31/2023] [Accepted: 06/06/2023] [Indexed: 06/21/2023] Open
Abstract
Motility is an essential factor for an organism's survival and diversification. With the advent of novel single-cell technologies, analytical frameworks, and theoretical methods, we can begin to probe the complex lives of microscopic motile organisms and answer the intertwining biological and physical questions of how these diverse lifeforms navigate their surroundings. Herein, we summarize the main mechanisms of microscale motility and give an overview of different experimental, analytical, and mathematical methods used to study them across different scales encompassing the molecular-, individual-, to population-level. We identify transferable techniques, pressing challenges, and future directions in the field. This review can serve as a starting point for researchers who are interested in exploring and quantifying the movements of organisms in the microscale world.
Collapse
Affiliation(s)
| | | | - Rebecca N Poon
- Living Systems Institute, University of Exeter, Stocker Road, EX4 4QD, Exeter, UK
| | - Alexander K Boggon
- Living Systems Institute, University of Exeter, Stocker Road, EX4 4QD, Exeter, UK
| | - Samuel A Bentley
- Living Systems Institute, University of Exeter, Stocker Road, EX4 4QD, Exeter, UK
| | - Dario Cortese
- Living Systems Institute, University of Exeter, Stocker Road, EX4 4QD, Exeter, UK
| | - Kirsty Y Wan
- Living Systems Institute, University of Exeter, Stocker Road, EX4 4QD, Exeter, UK
| |
Collapse
|
5
|
Moroz LL, Romanova DY. Chemical cognition: chemoconnectomics and convergent evolution of integrative systems in animals. Anim Cogn 2023; 26:1851-1864. [PMID: 38015282 PMCID: PMC11106658 DOI: 10.1007/s10071-023-01833-7] [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] [Accepted: 11/16/2023] [Indexed: 11/29/2023]
Abstract
Neurons underpin cognition in animals. However, the roots of animal cognition are elusive from both mechanistic and evolutionary standpoints. Two conceptual frameworks both highlight and promise to address these challenges. First, we discuss evidence that animal neural and other integrative systems evolved more than once (convergent evolution) within basal metazoan lineages, giving us unique experiments by Nature for future studies. The most remarkable examples are neural systems in ctenophores and neuroid-like systems in placozoans and sponges. Second, in addition to classical synaptic wiring, a chemical connectome mediated by hundreds of signal molecules operates in tandem with neurons and is the most information-rich source of emerging properties and adaptability. The major gap-dynamic, multifunctional chemical micro-environments in nervous systems-is not understood well. Thus, novel tools and information are needed to establish mechanistic links between orchestrated, yet cell-specific, volume transmission and behaviors. Uniting what we call chemoconnectomics and analyses of the cellular bases of behavior in basal metazoan lineages arguably would form the foundation for deciphering the origins and early evolution of elementary cognition and intelligence.
Collapse
Affiliation(s)
- Leonid L Moroz
- Department of Neuroscience, University of Florida, Gainesville, USA.
- Whitney Laboratory for Marine Bioscience, University of Florida, Saint Augustine, USA.
| | - Daria Y Romanova
- Institute of Higher Nervous Activity and Neurophysiology of RAS, Moscow, Russia
| |
Collapse
|
6
|
Elkhatib W, Yanez-Guerra LA, Mayorova TD, Currie MA, Singh A, Perera M, Gauberg J, Senatore A. Function and phylogeny support the independent evolution of an ASIC-like Deg/ENaC channel in the Placozoa. Commun Biol 2023; 6:951. [PMID: 37723223 PMCID: PMC10507113 DOI: 10.1038/s42003-023-05312-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 09/01/2023] [Indexed: 09/20/2023] Open
Abstract
ASIC channels are bilaterian proton-gated sodium channels belonging to the large and functionally-diverse Deg/ENaC family that also includes peptide- and mechanically-gated channels. Here, we report that the non-bilaterian invertebrate Trichoplax adhaerens possesses a proton-activated Deg/ENaC channel, TadNaC2, with a unique combination of biophysical features including tachyphylaxis like ASIC1a, reduced proton sensitivity like ASIC2a, biphasic macroscopic currents like ASIC3, as well as low sensitivity to the Deg/ENaC channel blocker amiloride and Ca2+ ions. Structural modeling and mutation analyses reveal that TadNaC2 proton gating is different from ASIC channels, lacking key molecular determinants, and involving unique residues within the palm and finger regions. Phylogenetic analysis reveals that a monophyletic clade of T. adhaerens Deg/ENaC channels, which includes TadNaC2, is phylogenetically distinct from ASIC channels, instead forming a clade with BASIC channels. Altogether, this work suggests that ASIC-like channels evolved independently in T. adhaerens and its phylum Placozoa. Our phylogenetic analysis also identifies several clades of uncharacterized metazoan Deg/ENaC channels, and provides phylogenetic evidence for the existence of Deg/ENaC channels outside of Metazoa, present in the gene data of select unicellular heterokont and filasterea-related species.
Collapse
Affiliation(s)
- Wassim Elkhatib
- Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, ON, L5L 1C6, Canada
- Department of Cell and Systems Biology, University of Toronto, 25 Harbord Street, Toronto, ON, M5S 3G5, Canada
| | - Luis A Yanez-Guerra
- Living Systems Institute, University of Exeter, Stocker Road, Exeter, EX4 4QD, England
| | | | - Mark A Currie
- Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, ON, L5L 1C6, Canada
- Department of Cell and Systems Biology, University of Toronto, 25 Harbord Street, Toronto, ON, M5S 3G5, Canada
| | - Anhadvir Singh
- Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, ON, L5L 1C6, Canada
- Department of Cell and Systems Biology, University of Toronto, 25 Harbord Street, Toronto, ON, M5S 3G5, Canada
| | - Maria Perera
- Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, ON, L5L 1C6, Canada
- Department of Cell and Systems Biology, University of Toronto, 25 Harbord Street, Toronto, ON, M5S 3G5, Canada
| | - Julia Gauberg
- Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, ON, L5L 1C6, Canada
- Department of Cell and Systems Biology, University of Toronto, 25 Harbord Street, Toronto, ON, M5S 3G5, Canada
| | - Adriano Senatore
- Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, ON, L5L 1C6, Canada.
- Department of Cell and Systems Biology, University of Toronto, 25 Harbord Street, Toronto, ON, M5S 3G5, Canada.
| |
Collapse
|
7
|
Nikitin MA, Romanova DY, Borman SI, Moroz LL. Amino acids integrate behaviors in nerveless placozoans. Front Neurosci 2023; 17:1125624. [PMID: 37123368 PMCID: PMC10133484 DOI: 10.3389/fnins.2023.1125624] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 03/10/2023] [Indexed: 05/02/2023] Open
Abstract
Placozoans are the simplest known free-living animals without recognized neurons and muscles but a complex behavioral repertoire. However, mechanisms and cellular bases of behavioral coordination are unknown. Here, using Trichoplax adhaerens as a model, we described 0.02-0.002 Hz oscillations in locomotory and feeding patterns as evidence of complex multicellular integration; and showed their dependence on the endogenous secretion of signal molecules. Evolutionary conserved low-molecular-weight transmitters (glutamate, aspartate, glycine, GABA, and ATP) acted as coordinators of distinct locomotory and feeding patterns. Specifically, L-glutamate induced and partially mimicked endogenous feeding cycles, whereas glycine and GABA suppressed feeding. ATP-modified feeding is complex, first causing feeding-like cycles and then suppressing feeding. Trichoplax locomotion was modulated by glycine, GABA, and, surprisingly, by animals' own mucus trails. Mucus triples locomotory speed compared to clean substrates. Glycine and GABA increased the frequency of turns. The effects of the amino acids are likely mediated by numerous receptors (R), including those from ionotropic GluRs, metabotropic GluRs, and GABA-BR families. Eighty-five of these receptors are encoded in the Trichoplax genome, more than in any other animal sequenced. Phylogenetic reconstructions illuminate massive lineage-specific expansions of amino acid receptors in Placozoa, Cnidaria, and Porifera and parallel evolution of nutritional sensing. Furthermore, we view the integration of feeding behaviors in nerveless animals by amino acids as ancestral exaptations that pave the way for co-options of glutamate, glycine, GABA, and ATP as classical neurotransmitters in eumetazoans.
Collapse
Affiliation(s)
- Mikhail A. Nikitin
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Daria Y. Romanova
- Institute of Higher Nervous Activity and Neurophysiology of RAS, Moscow, Russia
| | - Simkha I. Borman
- Koltzov Institute of Developmental Biology Russian Academy of Sciences, Moscow, Russia
| | - Leonid L. Moroz
- Departments of Neuroscience and McKnight Brain Institute, University of Florida, Gainesville, FL, United States
- Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL, United States
- *Correspondence: Leonid L. Moroz,
| |
Collapse
|
8
|
Moroz LL, Romanova DY. Alternative neural systems: What is a neuron? (Ctenophores, sponges and placozoans). Front Cell Dev Biol 2022; 10:1071961. [PMID: 36619868 PMCID: PMC9816575 DOI: 10.3389/fcell.2022.1071961] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 12/13/2022] [Indexed: 12/24/2022] Open
Abstract
How to make a neuron, a synapse, and a neural circuit? Is there only one 'design' for a neural architecture with a universally shared genomic blueprint across species? The brief answer is "No." Four early divergent lineages from the nerveless common ancestor of all animals independently evolved distinct neuroid-type integrative systems. One of these is a subset of neural nets in comb jellies with unique synapses; the second lineage is the well-known Cnidaria + Bilateria; the two others are non-synaptic neuroid systems in sponges and placozoans. By integrating scRNA-seq and microscopy data, we revise the definition of neurons as synaptically-coupled polarized and highly heterogenous secretory cells at the top of behavioral hierarchies with learning capabilities. This physiological (not phylogenetic) definition separates 'true' neurons from non-synaptically and gap junction-coupled integrative systems executing more stereotyped behaviors. Growing evidence supports the hypothesis of multiple origins of neurons and synapses. Thus, many non-bilaterian and bilaterian neuronal classes, circuits or systems are considered functional rather than genetic categories, composed of non-homologous cell types. In summary, little-explored examples of convergent neuronal evolution in representatives of early branching metazoans provide conceptually novel microanatomical and physiological architectures of behavioral controls in animals with prospects of neuro-engineering and synthetic biology.
Collapse
Affiliation(s)
- Leonid L. Moroz
- Departments of Neuroscience and McKnight Brain Institute, University of Florida, Gainesville, FL, United States,Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL, United States,*Correspondence: Leonid L. Moroz, ; Daria Y. Romanova,
| | - Daria Y. Romanova
- Institute of Higher Nervous Activity and Neurophysiology of RAS, 5A Butlerova, Moscow, Russia,*Correspondence: Leonid L. Moroz, ; Daria Y. Romanova,
| |
Collapse
|
9
|
Letsinger AC, Yang F, Menon R, Little-Letsinger SE, Granados JZ, Breidenbach B, Iyer AR, Padovani TC, Nagel EC, Jayaraman A, Lightfoot JT. Reduced Wheel Running via a High-Fat Diet Is Reversed by a Chow Diet with No Added Benefit from Fecal Microbial Transplants. Med Sci Sports Exerc 2022; 54:1437-1447. [PMID: 35969165 DOI: 10.1249/mss.0000000000002941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE Chronic overfeeding via a high-fat/high-sugar (HFHS) diet decreases wheel running and substantially alters the gut metabolome of C57BL/6J mice. In this study, we tested the hypothesis that fecal microbial transplants can modulate the effect of diet on wheel running. METHODS Singly housed, 6-wk-old male C57BL/6J mice were fed either a grain-based diet (CHOW) or HFHS diet and provided a running wheel for 13 wk. Low-active, HFHS-exposed mice were then either switched to a CHOW diet and given an oral fecal microbial transplant from mice fed the CHOW diet, switched to a CHOW diet and given a sham transplant, or remained on the HFHS diet and given a fecal microbial transplant from mice fed the CHOW diet. Total wheel running, nutrient intake, body composition, fecal microbial composition, fecal metabolite composition, and liver steatosis were measured at various times throughout the study. RESULTS We found that an HFHS diet decreases wheel running activity, increases body fat, and decreases microbial alpha diversity compared with a CHOW diet. Improvements in wheel running, body composition, and microbial alpha diversity were accomplished within 2 wk for mice switched from an HFHS diet to a CHOW diet with no clear evidence of an added benefit from fecal transplants. A fecal transplant from mice fed a CHOW diet without altering diet did not improve wheel running or body composition. Wheel running, body composition, fecal microbial composition, fecal metabolite composition, and liver steatosis percentage were primarily determined by diet. CONCLUSIONS Our results suggest that diet is a primary mediator of wheel running with no clear effect from fecal microbial transplants.
Collapse
Affiliation(s)
- Ayland C Letsinger
- The Department of Health Kinesiology, Texas A&M University, College Station, TX
| | - Fang Yang
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX
| | - Rani Menon
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX
| | | | - Jorge Z Granados
- The Department of Health Kinesiology, Texas A&M University, College Station, TX
| | - Brianne Breidenbach
- The Department of Health Kinesiology, Texas A&M University, College Station, TX
| | - Anjushree R Iyer
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX
| | | | - Edward C Nagel
- The Department of Health Kinesiology, Texas A&M University, College Station, TX
| | - Arul Jayaraman
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX
| | - J Timothy Lightfoot
- The Department of Health Kinesiology, Texas A&M University, College Station, TX
| |
Collapse
|
10
|
Kuyyamudi C, Menon SN, Sinha S. Contact-mediated signaling enables disorder-driven transitions in cellular assemblies. Phys Rev E 2022; 106:L022401. [PMID: 36109907 DOI: 10.1103/physreve.106.l022401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 08/02/2022] [Indexed: 06/15/2023]
Abstract
We show that, when cells communicate by contact-mediated interactions, heterogeneity in cell shapes and sizes leads to qualitatively distinct collective behavior in the tissue. For intercellular coupling that implements lateral inhibition, such disorder-driven transitions can substantially alter the asymptotic pattern of differentiated cells by modulating their fate choice through changes in the neighborhood geometry. In addition, when contact-induced signals influence inherent cellular oscillations, disorder leads to the emergence of functionally relevant partially-ordered dynamical states.
Collapse
Affiliation(s)
- Chandrashekar Kuyyamudi
- The Institute of Mathematical Sciences, CIT Campus, Taramani, Chennai 600113, India
- Homi Bhabha National Institute, Training School Complex, Anushaktinagar, Mumbai 400 094, India
| | - Shakti N Menon
- The Institute of Mathematical Sciences, CIT Campus, Taramani, Chennai 600113, India
| | - Sitabhra Sinha
- The Institute of Mathematical Sciences, CIT Campus, Taramani, Chennai 600113, India
- Homi Bhabha National Institute, Training School Complex, Anushaktinagar, Mumbai 400 094, India
| |
Collapse
|
11
|
Romanova DY, Nikitin MA, Shchenkov SV, Moroz LL. Expanding of Life Strategies in Placozoa: Insights From Long-Term Culturing of Trichoplax and Hoilungia. Front Cell Dev Biol 2022; 10:823283. [PMID: 35223848 PMCID: PMC8864292 DOI: 10.3389/fcell.2022.823283] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Accepted: 01/20/2022] [Indexed: 12/05/2022] Open
Abstract
Placozoans are essential reference species for understanding the origins and evolution of animal organization. However, little is known about their life strategies in natural habitats. Here, by maintaining long-term culturing for four species of Trichoplax and Hoilungia, we extend our knowledge about feeding and reproductive adaptations relevant to the diversity of life forms and immune mechanisms. Three modes of population dynamics depended upon feeding sources, including induction of social behaviors, morphogenesis, and reproductive strategies. In addition to fission, representatives of all species produced “swarmers” (a separate vegetative reproduction stage), which could also be formed from the lower epithelium with greater cell-type diversity. We monitored the formation of specialized spheroid structures from the upper cell layer in aging culture. These “spheres” could be transformed into juvenile animals under favorable conditions. We hypothesize that spheroid structures represent a component of the innate immune defense response with the involvement of fiber cells. Finally, we showed that regeneration could be a part of the adaptive reproductive strategies in placozoans and a unique experimental model for regenerative biology.
Collapse
Affiliation(s)
- Daria Y. Romanova
- Institute of Higher Nervous Activity and Neurophysiology of RAS, Moscow, Russia
- *Correspondence: Daria Y. Romanova, ; Leonid L. Moroz,
| | - Mikhail A. Nikitin
- Belozersky Institute for Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
- Kharkevich Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow, Russia
| | - Sergey V. Shchenkov
- Department of Invertebrate Zoology, Faculty of Biology, Saint Petersburg State University, Saint Petersburg, Russia
| | - Leonid L. Moroz
- Departments of Neuroscience and McKnight Brain Institute, University of Florida, Gainesville, FL, United States
- Whitney Laboratory for Marine Biosciences, University of Florida, St. Augustine, FL, United States
- *Correspondence: Daria Y. Romanova, ; Leonid L. Moroz,
| |
Collapse
|
12
|
Osigus HJ, Eitel M, Horn K, Kamm K, Kosubek-Langer J, Schmidt MJ, Hadrys H, Schierwater B. Studying Placozoa WBR in the Simplest Metazoan Animal, Trichoplax adhaerens. Methods Mol Biol 2022; 2450:121-133. [PMID: 35359305 PMCID: PMC9761494 DOI: 10.1007/978-1-0716-2172-1_6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Placozoans are a promising model system to study fundamental regeneration processes in a morphologically and genetically very simple animal. We here provide a brief introduction to the enigmatic Placozoa and summarize the state of the art of animal handling and experimental manipulation possibilities.
Collapse
Affiliation(s)
- Hans-Jürgen Osigus
- Institut für Tierökologie, Stiftung Tierärztliche Hochschule Hannover, Hannover, Germany
| | - Michael Eitel
- Department of Earth and Environmental Sciences, Paleontology and Geobiology, GeoBio-Center, Ludwig-Maximilians Universität München, Munich, Germany
| | - Karolin Horn
- Institut für Tierökologie, Stiftung Tierärztliche Hochschule Hannover, Hannover, Germany
| | - Kai Kamm
- Institut für Tierökologie, Stiftung Tierärztliche Hochschule Hannover, Hannover, Germany
| | - Jennifer Kosubek-Langer
- Institut für Tierökologie, Stiftung Tierärztliche Hochschule Hannover, Hannover, Germany
- Department of Animal Behavior, Freie Universität Berlin, Berlin, Germany
| | | | - Heike Hadrys
- Institut für Tierökologie, Stiftung Tierärztliche Hochschule Hannover, Hannover, Germany
| | - Bernd Schierwater
- Institut für Tierökologie, Stiftung Tierärztliche Hochschule Hannover, Hannover, Germany.
| |
Collapse
|
13
|
Mayorova TD, Hammar K, Jung JH, Aronova MA, Zhang G, Winters CA, Reese TS, Smith CL. Placozoan fiber cells: mediators of innate immunity and participants in wound healing. Sci Rep 2021; 11:23343. [PMID: 34857844 PMCID: PMC8639732 DOI: 10.1038/s41598-021-02735-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 11/19/2021] [Indexed: 12/22/2022] Open
Abstract
Placozoa is a phylum of non-bilaterian marine animals. These small, flat organisms adhere to the substrate via their densely ciliated ventral epithelium, which mediates mucociliary locomotion and nutrient uptake. They have only six morphological cell types, including one, fiber cells, for which functional data is lacking. Fiber cells are non-epithelial cells with multiple processes. We used electron and light microscopic approaches to unravel the roles of fiber cells in Trichoplax adhaerens, a representative member of the phylum. Three-dimensional reconstructions of serial sections of Trichoplax showed that each fiber cell is in contact with several other cells. Examination of fiber cells in thin sections and observations of live dissociated fiber cells demonstrated that they phagocytose cell debris and bacteria. In situ hybridization confirmed that fiber cells express genes involved in phagocytic activity. Fiber cells also are involved in wound healing as evidenced from microsurgery experiments. Based on these observations we conclude that fiber cells are multi-purpose macrophage-like cells. Macrophage-like cells have been described in Porifera, Ctenophora, and Cnidaria and are widespread among Bilateria, but our study is the first to show that Placozoa possesses this cell type. The phylogenetic distribution of macrophage-like cells suggests that they appeared early in metazoan evolution.
Collapse
Affiliation(s)
- Tatiana D Mayorova
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 49 Convent Drive, Bethesda, MD, 20892, USA.
| | - Katherine Hammar
- Central Microscopy Facility, Marine Biological Laboratory, 7 MBL Street, Woods Hole, MA, 02543, USA
| | - Jae H Jung
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 49 Convent Drive, Bethesda, MD, 20892, USA
| | - Maria A Aronova
- Laboratory of Cellular Imaging and Macromolecular Biophysics, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD, USA
| | - Guofeng Zhang
- Laboratory of Cellular Imaging and Macromolecular Biophysics, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD, USA
| | - Christine A Winters
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 49 Convent Drive, Bethesda, MD, 20892, USA
| | - Thomas S Reese
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 49 Convent Drive, Bethesda, MD, 20892, USA
| | - Carolyn L Smith
- Light Imaging Facility, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 35 Convent Drive, Bethesda, MD, 20892, USA
| |
Collapse
|
14
|
Schierwater B, Osigus HJ, Bergmann T, Blackstone NW, Hadrys H, Hauslage J, Humbert PO, Kamm K, Kvansakul M, Wysocki K, DeSalle R. The enigmatic Placozoa part 1: Exploring evolutionary controversies and poor ecological knowledge. Bioessays 2021; 43:e2100080. [PMID: 34472126 DOI: 10.1002/bies.202100080] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 07/21/2021] [Accepted: 08/16/2021] [Indexed: 12/13/2022]
Abstract
The placozoan Trichoplax adhaerens is a tiny hairy plate and more simply organized than any other living metazoan. After its original description by F.E. Schulze in 1883, it attracted attention as a potential model for the ancestral state of metazoan organization, the "Urmetazoon". Trichoplax lacks any kind of symmetry, organs, nerve cells, muscle cells, basal lamina, and extracellular matrix. Furthermore, the placozoan genome is the smallest (not secondarily reduced) genome of all metazoan genomes. It harbors a remarkably rich diversity of genes and has been considered the best living surrogate for a metazoan ancestor genome. The phylum Placozoa presently harbors three formally described species, while several dozen "cryptic" species are yet awaiting their description. The phylogenetic position of placozoans has recently become a contested arena for modern phylogenetic analyses and view-driven claims. Trichoplax offers unique prospects for understanding the minimal requirements of metazoan animal organization and their corresponding malfunctions.
Collapse
Affiliation(s)
- Bernd Schierwater
- Institute of Animal Ecology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Hans-Jürgen Osigus
- Institute of Animal Ecology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Tjard Bergmann
- Institute of Animal Ecology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Neil W Blackstone
- Department of Biological Sciences, Northern Illinois University, DeKalb, Illinois, USA
| | - Heike Hadrys
- Institute of Animal Ecology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Jens Hauslage
- Gravitational Biology, Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany
| | - Patrick O Humbert
- Department of Biochemistry & Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia.,Research Centre for Molecular Cancer Prevention, La Trobe University, Melbourne, Victoria, 3086, Australia
| | - Kai Kamm
- Institute of Animal Ecology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Marc Kvansakul
- Department of Biochemistry & Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia.,Research Centre for Molecular Cancer Prevention, La Trobe University, Melbourne, Victoria, 3086, Australia
| | - Kathrin Wysocki
- Institute of Animal Ecology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Rob DeSalle
- American Museum of Natural History, New York, New York, USA
| |
Collapse
|
15
|
Romanova DY, Varoqueaux F, Daraspe J, Nikitin MA, Eitel M, Fasshauer D, Moroz LL. Hidden cell diversity in Placozoa: ultrastructural insights from Hoilungia hongkongensis. Cell Tissue Res 2021; 385:623-637. [PMID: 33876313 PMCID: PMC8523601 DOI: 10.1007/s00441-021-03459-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 03/31/2021] [Indexed: 12/17/2022]
Abstract
From a morphological point of view, placozoans are among the most simple free-living animals. This enigmatic phylum is critical for our understanding of the evolution of animals and their cell types. Their millimeter-sized, disc-like bodies consist of only three cell layers that are shaped by roughly seven major cell types. Placozoans lack muscle cells and neurons but are able to move using their ciliated lower surface and take up food in a highly coordinated manner. Intriguingly, the genome of Trichoplax adhaerens, the founding member of the enigmatic phylum, has disclosed a surprising level of genetic complexity. Moreover, recent molecular and functional investigations have uncovered a much larger, so-far hidden cell-type diversity. Here, we have extended the microanatomical characterization of a recently described placozoan species-Hoilungia hongkongensis. In H. hongkongensis, we recognized the established canonical three-layered placozoan body plan but also came across several morphologically distinct and potentially novel cell types, among them novel gland cells and "shiny spheres"-bearing cells at the upper epithelium. Thus, the diversity of cell types in placozoans is indeed higher than anticipated.
Collapse
Affiliation(s)
- Daria Y Romanova
- Department of Fundamental Neurosciences, University of Lausanne, 1005, Lausanne, Switzerland.
- Cellular Neurobiology of Learning Lab, Institute of Higher Nervous Activity and Neurophysiology, Moscow, 117485, Russia.
| | - Frédérique Varoqueaux
- Department of Fundamental Neurosciences, University of Lausanne, 1005, Lausanne, Switzerland
- Department of Computational Biology, University of Lausanne, 1015, Lausanne, Switzerland
| | - Jean Daraspe
- Electron Microscopy Facility, University of Lausanne, Lausanne, Switzerland
| | - Mikhail A Nikitin
- Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow, 119991, Russia
- Kharkevich Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow, 127994, Russia
| | - Michael Eitel
- Department of Earth and Environmental Sciences, Paleontology and Geobiology, Ludwig-Maximilians Universität München, Munich, Germany
| | - Dirk Fasshauer
- Department of Fundamental Neurosciences, University of Lausanne, 1005, Lausanne, Switzerland.
- Department of Computational Biology, University of Lausanne, 1015, Lausanne, Switzerland.
| | - Leonid L Moroz
- Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL, 32080, USA.
- Departments of Neuroscience and McKnight Brain Institute, University of Florida, Gainesville, FL, 32610, USA.
| |
Collapse
|
16
|
Moroz LL, Romanova DY. Selective Advantages of Synapses in Evolution. Front Cell Dev Biol 2021; 9:726563. [PMID: 34490275 PMCID: PMC8417881 DOI: 10.3389/fcell.2021.726563] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 07/29/2021] [Indexed: 12/23/2022] Open
Affiliation(s)
- Leonid L. Moroz
- Departments of Neuroscience and McKnight Brain Institute, University of Florida, Gainesville, FL, United States
- Whitney Laboratory for Marine Biosciences, University of Florida, St. Augustine, FL, United States
| | - Daria Y. Romanova
- Lab of Cellular Neurobiology of Learning, Institute of Higher Nervous Activity and Neurophysiology of Russian Academy of Sciences, Moscow, Russia
| |
Collapse
|
17
|
Moroz LL, Nikitin MA, Poličar PG, Kohn AB, Romanova DY. Evolution of glutamatergic signaling and synapses. Neuropharmacology 2021; 199:108740. [PMID: 34343611 DOI: 10.1016/j.neuropharm.2021.108740] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 07/28/2021] [Accepted: 07/29/2021] [Indexed: 12/13/2022]
Abstract
Glutamate (Glu) is the primary excitatory transmitter in the mammalian brain. But, we know little about the evolutionary history of this adaptation, including the selection of l-glutamate as a signaling molecule in the first place. Here, we used comparative metabolomics and genomic data to reconstruct the genealogy of glutamatergic signaling. The origin of Glu-mediated communications might be traced to primordial nitrogen and carbon metabolic pathways. The versatile chemistry of L-Glu placed this molecule at the crossroad of cellular biochemistry as one of the most abundant metabolites. From there, innovations multiplied. Many stress factors or injuries could increase extracellular glutamate concentration, which led to the development of modular molecular systems for its rapid sensing in bacteria and archaea. More than 20 evolutionarily distinct families of ionotropic glutamate receptors (iGluRs) have been identified in eukaryotes. The domain compositions of iGluRs correlate with the origins of multicellularity in eukaryotes. Although L-Glu was recruited as a neuro-muscular transmitter in the early-branching metazoans, it was predominantly a non-neuronal messenger, with a possibility that glutamatergic synapses evolved more than once. Furthermore, the molecular secretory complexity of glutamatergic synapses in invertebrates (e.g., Aplysia) can exceed their vertebrate counterparts. Comparative genomics also revealed 15+ subfamilies of iGluRs across Metazoa. However, most of this ancestral diversity had been lost in the vertebrate lineage, preserving AMPA, Kainate, Delta, and NMDA receptors. The widespread expansion of glutamate synapses in the cortical areas might be associated with the enhanced metabolic demands of the complex brain and compartmentalization of Glu signaling within modular neuronal ensembles.
Collapse
Affiliation(s)
- Leonid L Moroz
- Whitney Laboratory for Marine Biosciences, University of Florida, St. Augustine, FL, 32080, USA; Departments of Neuroscience and McKnight Brain Institute, University of Florida, Gainesville, FL, 32610, USA.
| | - Mikhail A Nikitin
- Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow, 119991, Russia; Kharkevich Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow, 127994, Russia
| | - Pavlin G Poličar
- Whitney Laboratory for Marine Biosciences, University of Florida, St. Augustine, FL, 32080, USA; Faculty of Computer and Information Science, University of Ljubljana, SI-1000, Ljubljana, Slovenia
| | - Andrea B Kohn
- Whitney Laboratory for Marine Biosciences, University of Florida, St. Augustine, FL, 32080, USA
| | - Daria Y Romanova
- Cellular Neurobiology of Learning Lab, Institute of Higher Nervous Activity and Neurophysiology, Moscow, 117485, Russia.
| |
Collapse
|
18
|
Dunn FS, Liu AG, Grazhdankin DV, Vixseboxse P, Flannery-Sutherland J, Green E, Harris S, Wilby PR, Donoghue PCJ. The developmental biology of Charnia and the eumetazoan affinity of the Ediacaran rangeomorphs. SCIENCE ADVANCES 2021; 7:eabe0291. [PMID: 34301594 PMCID: PMC8302126 DOI: 10.1126/sciadv.abe0291] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 06/09/2021] [Indexed: 06/13/2023]
Abstract
Molecular timescales estimate that early animal lineages diverged tens of millions of years before their earliest unequivocal fossil evidence. The Ediacaran macrobiota (~574 to 538 million years ago) are largely eschewed from this debate, primarily due to their extreme phylogenetic uncertainty, but remain germane. We characterize the development of Charnia masoni and establish the affinity of rangeomorphs, among the oldest and most enigmatic components of the Ediacaran macrobiota. We provide the first direct evidence for the internal interconnected nature of rangeomorphs and show that Charnia was constructed of repeated branches that derived successively from pre-existing branches. We find homology and rationalize morphogenesis between disparate rangeomorph taxa, before producing a phylogenetic analysis, resolving Charnia as a stem-eumetazoan and expanding the anatomical disparity of that group to include a long-extinct bodyplan. These data bring competing records of early animal evolution into closer agreement, reformulating our understanding of the evolutionary emergence of animal bodyplans.
Collapse
Affiliation(s)
- Frances S Dunn
- Oxford University Museum of Natural History, University of Oxford, Parks Road, Oxford OX1 3PW, UK.
- British Geological Survey, Nicker Hill, Keyworth, Nottingham NG12 5GG, UK
- School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Alexander G Liu
- Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK
| | - Dmitriy V Grazhdankin
- Trofimuk Institute of Petroleum Geology and Geophysics, Prospekt Akademika Koptyuga 3, Novosibirsk 630090, Russia
- Novosibirsk State University, Pirogova Street 1, Novosibirsk 630090, Russia
| | - Philip Vixseboxse
- School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Joseph Flannery-Sutherland
- School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Emily Green
- School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Simon Harris
- British Geological Survey, Nicker Hill, Keyworth, Nottingham NG12 5GG, UK
| | - Philip R Wilby
- British Geological Survey, Nicker Hill, Keyworth, Nottingham NG12 5GG, UK
- School of Geography, Geology and the Environment, University of Leicester, University Road, Leicester LE1 7RH, UK
| | - Philip C J Donoghue
- School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol BS8 1TQ, UK
| |
Collapse
|
19
|
Glycine as a signaling molecule and chemoattractant in Trichoplax (Placozoa): insights into the early evolution of neurotransmitters. Neuroreport 2021; 31:490-497. [PMID: 32243353 DOI: 10.1097/wnr.0000000000001436] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The origin and early evolution of neurotransmitter signaling in animals are unclear due to limited comparative information, primarily about prebilaterian animals. Here, we performed the comparative survey of signal molecules in placozoans - the simplest known free-living animals without canonical synapses, but with complex behaviors. First, using capillary electrophoresis with laser-induced fluorescence detection, we performed microchemical analyses of transmitter candidates in Trichoplax adhaerens - the classical reference species in comparative biology. We showed that the endogenous level of glycine (about 3 mM) was significantly higher than for other candidates such as L-glutamate, L-aspartate, or gamma-aminobutyric acid. Neither serotonin nor dopamine were detected. The absolute glycine concentrations in Trichoplax were even higher than we measured in ctenophores (Beroe) and cnidarians (Aequorea). We found that at millimolar concentrations of glycine (similar to the endogenous level), induced muscle-like contractions in free behaving animals. But after long incubation (24 h), 10 M of glycine could induce cytotoxicity and cell dissociation. In contrast, micromolar concentrations (10-10 M) increased Trichoplax ciliated locomotion, suggesting that glycine might act as an endogenous signal molecule. However, we showed than glycine (10 M) can also be a chemoattractant (a guiding factor for food sources), and therefore, act as the exogenous signal. These findings provide an evolutionary base for the origin of transmitters as a result of the interplay between exogenous and endogenous signaling systems early in animal evolution.
Collapse
|
20
|
Kuznetsov AV, Vainer VI, Volkova YM, Kartashov LE. Motility disorders and disintegration into separate cells of Trichoplax sp. H2 in the presence of Zn 2+ ions and L-cysteine molecules: A systems approach. Biosystems 2021; 206:104444. [PMID: 34023485 DOI: 10.1016/j.biosystems.2021.104444] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 05/08/2021] [Accepted: 05/09/2021] [Indexed: 01/01/2023]
Abstract
Placozoa remain an ancient multicellular system with a dynamic body structure where calcium ions carry out a primary role in maintaining the integrity of the entire animal. Zinc ions can compete with calcium ions adsorption. We studied the effect of zinc ions and l-cysteine molecules on the interaction of Trichoplax sp. H2 cells. The regularity of formless motion was diminished in the presence of 20-25 μM of Zn2+ ions leading to the formation of branching animal forms. Locomotor ciliated cells moved chaotically and independently of each other leaving the Trichoplax body and opening a network of fiber cells. Application of 100 μM cysteine resulted in dissociation of the plate into separate cells. The combined chemical treatment shifted the effect in a random sample of animals toward disintegration, i.e. initially leading to disorder of collective cell movement and then to total body fragmentation. Two dissociation patterns of Trichoplax plate as "expanding ring" and "bicycle wheel" were revealed. Analysis of the interaction of Ca2+ and Zn2+ ions with cadherin showed that more than half (54%) of the amino acid residues with which Ca2+ and Zn2+ ions bind are common. The contact interaction of cells covered by the cadherin molecules is important for the coordinated movements of Trichoplax organism, while zinc ions are capable to break junctions between the cells. The involvement of other players, for example, l-cysteine in the regulation of Ca2+-dependent adhesion may be critical leading to the typical dissociation of Trichoplax body like in a calcium-free environment. A hypothesis about the essential role of calcium ions in the emergence of Metazoa ancestor is proposed.
Collapse
Affiliation(s)
- A V Kuznetsov
- A.O. Kovalevsky Institute of Biology of the Southern Seas RAS, Leninsky Avenue 38, Moscow, 119991, Russia.
| | - V I Vainer
- A.O. Kovalevsky Institute of Biology of the Southern Seas RAS, Leninsky Avenue 38, Moscow, 119991, Russia
| | - Yu M Volkova
- A.O. Kovalevsky Institute of Biology of the Southern Seas RAS, Leninsky Avenue 38, Moscow, 119991, Russia
| | - L E Kartashov
- A.O. Kovalevsky Institute of Biology of the Southern Seas RAS, Leninsky Avenue 38, Moscow, 119991, Russia
| |
Collapse
|
21
|
Moroz LL, Romanova DY, Kohn AB. Neural versus alternative integrative systems: molecular insights into origins of neurotransmitters. Philos Trans R Soc Lond B Biol Sci 2021; 376:20190762. [PMID: 33550949 PMCID: PMC7935107 DOI: 10.1098/rstb.2019.0762] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/23/2020] [Indexed: 12/18/2022] Open
Abstract
Transmitter signalling is the universal chemical language of any nervous system, but little is known about its early evolution. Here, we summarize data about the distribution and functions of neurotransmitter systems in basal metazoans as well as outline hypotheses of their origins. We explore the scenario that neurons arose from genetically different populations of secretory cells capable of volume chemical transmission and integration of behaviours without canonical synapses. The closest representation of this primordial organization is currently found in Placozoa, disk-like animals with the simplest known cell composition but complex behaviours. We propose that injury-related signalling was the evolutionary predecessor for integrative functions of early transmitters such as nitric oxide, ATP, protons, glutamate and small peptides. By contrast, acetylcholine, dopamine, noradrenaline, octopamine, serotonin and histamine were recruited as canonical neurotransmitters relatively later in animal evolution, only in bilaterians. Ligand-gated ion channels often preceded the establishment of novel neurotransmitter systems. Moreover, lineage-specific diversification of neurotransmitter receptors occurred in parallel within Cnidaria and several bilaterian lineages, including acoels. In summary, ancestral diversification of secretory signal molecules provides unique chemical microenvironments for behaviour-driven innovations that pave the way to complex brain functions and elementary cognition. This article is part of the theme issue 'Basal cognition: multicellularity, neurons and the cognitive lens'.
Collapse
Affiliation(s)
- Leonid L. Moroz
- Department of Neuroscience, McKnight Brain Institute and Whitney laboratory, University of Florida, 9505 Ocean shore Blvd, St Augustine, FL 32080, USA
| | - Daria Y. Romanova
- Laboratory of Cellular Neurobiology of Learning, Institute of Higher Nervous Activity and Neurophysiology of RAS, 5A Butlerova Street, Moscow 117485, Russia
| | - Andrea B. Kohn
- Department of Neuroscience, McKnight Brain Institute and Whitney laboratory, University of Florida, 9505 Ocean shore Blvd, St Augustine, FL 32080, USA
| |
Collapse
|
22
|
Smith CL, Mayorova TD, Winters CA, Reese TS, Leys SP, Heyland A. Microscopy Studies of Placozoans. Methods Mol Biol 2021; 2219:99-118. [PMID: 33074536 DOI: 10.1007/978-1-0716-0974-3_6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Trichoplax adhaerens is an enigmatic animal with an extraordinarily simple morphology and a cellular organization, which are the focus of current research. Protocols outlined here provide detailed descriptions of advanced techniques for light and electron microscopic studies of Trichoplax. Studies using these techniques have enhanced our understanding of cell type diversity and function in placozoans and have provided insight into the evolution, development, and physiology of this little understood group.
Collapse
Affiliation(s)
- Carolyn L Smith
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Tatiana D Mayorova
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Christine A Winters
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Thomas S Reese
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Sally P Leys
- Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada
| | - Andreas Heyland
- Department of Integrative Biology, College of Biological Science, University of Guelph, Guelph, ON, Canada.
| |
Collapse
|
23
|
Gauberg J, Senatore A, Heyland A. Functional Studies of Trichoplax adhaerens Voltage-Gated Calcium Channel Activity. Methods Mol Biol 2021; 2219:277-288. [PMID: 33074548 DOI: 10.1007/978-1-0716-0974-3_18] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Trichoplax adhaerens is a member of the phylum Placozoa, an enigmatic group of benthic animals with remarkably simple morphology. While initial work on these organisms has primarily focused on their morphology and the development of genomic resources, Trichoplax has received increased attention as a model for studying the evolution of nervous and sensory systems. This work is motivated by the fact that Trichoplax features distinct behaviours and responses to environmental stimuli. Therefore, much progress has been made in recent years on the molecular, cellular, and behavioral understanding of this organism. Methods outlined here provide hands-on approaches to cutting edge molecular and cellular techniques to record cellular activities in Trichoplax.
Collapse
Affiliation(s)
- Julia Gauberg
- Cell and Systems Biology, University of Toronto Mississauga, Mississauga, ON, Canada
| | - Adriano Senatore
- Cell and Systems Biology, University of Toronto Mississauga, Mississauga, ON, Canada
| | - Andreas Heyland
- Department of Integrative Biology, College of Biological Science, University of Guelph, Guelph, ON, Canada.
| |
Collapse
|
24
|
Gauberg J, Abdallah S, Elkhatib W, Harracksingh AN, Piekut T, Stanley EF, Senatore A. Conserved biophysical features of the Ca V2 presynaptic Ca 2+ channel homologue from the early-diverging animal Trichoplax adhaerens. J Biol Chem 2020; 295:18553-18578. [PMID: 33097592 PMCID: PMC7939481 DOI: 10.1074/jbc.ra120.015725] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 10/21/2020] [Indexed: 12/20/2022] Open
Abstract
The dominant role of CaV2 voltage-gated calcium channels for driving neurotransmitter release is broadly conserved. Given the overlapping functional properties of CaV2 and CaV1 channels, and less so CaV3 channels, it is unclear why there have not been major shifts toward dependence on other CaV channels for synaptic transmission. Here, we provide a structural and functional profile of the CaV2 channel cloned from the early-diverging animal Trichoplax adhaerens, which lacks a nervous system but possesses single gene homologues for CaV1-CaV3 channels. Remarkably, the highly divergent channel possesses similar features as human CaV2.1 and other CaV2 channels, including high voltage-activated currents that are larger in external Ba2+ than in Ca2+; voltage-dependent kinetics of activation, inactivation, and deactivation; and bimodal recovery from inactivation. Altogether, the functional profile of Trichoplax CaV2 suggests that the core features of presynaptic CaV2 channels were established early during animal evolution, after CaV1 and CaV2 channels emerged via proposed gene duplication from an ancestral CaV1/2 type channel. The Trichoplax channel was relatively insensitive to mammalian CaV2 channel blockers ω-agatoxin-IVA and ω-conotoxin-GVIA and to metal cation blockers Cd2+ and Ni2+ Also absent was the capacity for voltage-dependent G-protein inhibition by co-expressed Trichoplax Gβγ subunits, which nevertheless inhibited the human CaV2.1 channel, suggesting that this modulatory capacity evolved via changes in channel sequence/structure, and not G proteins. Last, the Trichoplax channel was immunolocalized in cells that express an endomorphin-like peptide implicated in cell signaling and locomotive behavior and other likely secretory cells, suggesting contributions to regulated exocytosis.
Collapse
Affiliation(s)
- Julia Gauberg
- Department of Biology, University of Toronto Mississauga, Mississauga, Ontario, Canada
| | - Salsabil Abdallah
- Department of Biology, University of Toronto Mississauga, Mississauga, Ontario, Canada
| | - Wassim Elkhatib
- Department of Biology, University of Toronto Mississauga, Mississauga, Ontario, Canada
| | - Alicia N Harracksingh
- Department of Biology, University of Toronto Mississauga, Mississauga, Ontario, Canada
| | - Thomas Piekut
- Department of Biology, University of Toronto Mississauga, Mississauga, Ontario, Canada
| | - Elise F Stanley
- Laboratory of Synaptic Transmission, Krembil Research Institute, Toronto, Ontario, Canada
| | - Adriano Senatore
- Department of Biology, University of Toronto Mississauga, Mississauga, Ontario, Canada.
| |
Collapse
|
25
|
Romanova DY, Smirnov IV, Nikitin MA, Kohn AB, Borman AI, Malyshev AY, Balaban PM, Moroz LL. Sodium action potentials in placozoa: Insights into behavioral integration and evolution of nerveless animals. Biochem Biophys Res Commun 2020; 532:120-126. [PMID: 32828537 DOI: 10.1016/j.bbrc.2020.08.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 08/09/2020] [Indexed: 01/20/2023]
Abstract
Placozoa are small disc-shaped animals, representing the simplest known, possibly ancestral, organization of free-living animals. With only six morphological distinct cell types, without any recognized neurons or muscle, placozoans exhibit fast effector reactions and complex behaviors. However, little is known about electrogenic mechanisms in these animals. Here, we showed the presence of rapid action potentials in four species of placozoans (Trichoplax adhaerens [H1 haplotype], Trichoplax sp.[H2], Hoilungia hongkongensis [H13], and Hoilungia sp. [H4]). These action potentials are sodium-dependent and can be inducible. The molecular analysis suggests the presence of 5-7 different types of voltage-gated sodium channels, which showed substantial evolutionary radiation compared to many other metazoans. Such unexpected diversity of sodium channels in early-branched metazoan lineages reflect both duplication events and parallel evolution of unique behavioral integration in these nerveless animals.
Collapse
Affiliation(s)
- Daria Y Romanova
- Institute of Higher Nervous Activity and Neurophysiology, Moscow, 117485, Russia.
| | - Ivan V Smirnov
- Institute of Higher Nervous Activity and Neurophysiology, Moscow, 117485, Russia
| | - Mikhail A Nikitin
- Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow, 119991, Russia
| | - Andrea B Kohn
- Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL, 32080, USA
| | - Alisa I Borman
- Department of Evolutionary Biology, Biological Faculty, Lomonosov Moscow State University, Moscow, 119991, Russia
| | - Alexey Y Malyshev
- Institute of Higher Nervous Activity and Neurophysiology, Moscow, 117485, Russia
| | - Pavel M Balaban
- Institute of Higher Nervous Activity and Neurophysiology, Moscow, 117485, Russia.
| | - Leonid L Moroz
- Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL, 32080, USA; Department of Neuroscience and McKnight Brain Institute, University of Florida, Gainesville, FL, 32610, USA.
| |
Collapse
|
26
|
Moroz LL, Romanova DY, Nikitin MA, Sohn D, Kohn AB, Neveu E, Varoqueaux F, Fasshauer D. The diversification and lineage-specific expansion of nitric oxide signaling in Placozoa: insights in the evolution of gaseous transmission. Sci Rep 2020; 10:13020. [PMID: 32747709 PMCID: PMC7400543 DOI: 10.1038/s41598-020-69851-w] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 07/16/2020] [Indexed: 12/11/2022] Open
Abstract
Nitric oxide (NO) is a ubiquitous gaseous messenger, but we know little about its early evolution. Here, we analyzed NO synthases (NOS) in four different species of placozoans-one of the early-branching animal lineages. In contrast to other invertebrates studied, Trichoplax and Hoilungia have three distinct NOS genes, including PDZ domain-containing NOS. Using ultra-sensitive capillary electrophoresis assays, we quantified nitrites (products of NO oxidation) and L-citrulline (co-product of NO synthesis from L-arginine), which were affected by NOS inhibitors confirming the presence of functional enzymes in Trichoplax. Using fluorescent single-molecule in situ hybridization, we showed that distinct NOSs are expressed in different subpopulations of cells, with a noticeable distribution close to the edge regions of Trichoplax. These data suggest both the compartmentalized release of NO and a greater diversity of cell types in placozoans than anticipated. NO receptor machinery includes both canonical and novel NIT-domain containing soluble guanylate cyclases as putative NO/nitrite/nitrate sensors. Thus, although Trichoplax and Hoilungia exemplify the morphologically simplest free-living animals, the complexity of NO-cGMP-mediated signaling in Placozoa is greater to those in vertebrates. This situation illuminates multiple lineage-specific diversifications of NOSs and NO/nitrite/nitrate sensors from the common ancestor of Metazoa and the preservation of conservative NOS architecture from prokaryotic ancestors.
Collapse
Affiliation(s)
- Leonid L Moroz
- Whitney Laboratory for Marine Bioscience and Departments of Neuroscience, University of Florida, St. Augustine and Gainesville, FL, 32080, USA.
| | - Daria Y Romanova
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, 117485, Russia
| | - Mikhail A Nikitin
- Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow, 119991, Russia
| | - Dosung Sohn
- Whitney Laboratory for Marine Bioscience and Departments of Neuroscience, University of Florida, St. Augustine and Gainesville, FL, 32080, USA
| | - Andrea B Kohn
- Whitney Laboratory for Marine Bioscience and Departments of Neuroscience, University of Florida, St. Augustine and Gainesville, FL, 32080, USA
| | - Emilie Neveu
- Department of Fundamental Neurosciences, University of Lausanne, 1005, Lausanne, Switzerland
| | - Frederique Varoqueaux
- Department of Fundamental Neurosciences, University of Lausanne, 1005, Lausanne, Switzerland
| | - Dirk Fasshauer
- Department of Fundamental Neurosciences, University of Lausanne, 1005, Lausanne, Switzerland
| |
Collapse
|
27
|
Kuznetsov AV, Kuleshova ON, Pronozin AY, Krivenko OV, Zavyalova OS. Effects of low frequency rectangular electric pulses on Trichoplax (Placozoa). ACTA ACUST UNITED AC 2020. [DOI: 10.21072/mbj.2020.05.2.05] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The effect of extremely low frequency electric and magnetic fields (ELF-EMF) on plants and animals including humans is quite a contentious issue. Little is known about ELF-EMF effect on hydrobionts, too. We studied the effect of square voltage waves of various amplitude, duration, and duty cycle, passed through seawater, on Trichoplax organisms as a possible test laboratory model. Three Placozoa strains, such as Trichoplax adhaerens (H1), Trichoplax sp. (H2), and Hoilungia hongkongensis (H13), were used in experiments. They were picked at the stationary growth phase. Arduino Uno electronics platform was used to generate a sequence of rectangular pulses of given duration and duty cycle with a frequency up to 2 kHz. Average voltage up to 500 mV was regulated by voltage divider circuit. Amlodipine, an inhibitor of calcium channel activity, was used to check the specificity of electrical pulse effect on voltage-gated calcium channels in Trichoplax. Experimental animals were investigated under a stereo microscope and stimulated by current-carrying electrodes placed close to a Trichoplax body. Variations in behavior and morphological characteristics of Trichoplax plate were studied. Stimulating and suppressing effects were identified. Experimental observations were recorded using photo and video techniques. Motion trajectories of individual animals were tracked. Increasing voltage pulses with fixed frequency of 20 Hz caused H2 haplotype individuals to leave “electrode zone” within several minutes at a voltage of 25 mV. They lost mobility in proportion to voltage rise and were paralyzed at a voltage of 500 mV. Therefore, a voltage of 50 mV was used in further experiments. An animal had more chance to move in various directions in experiments with two electrodes located on one side instead of both sides of Trichoplax. Direction of motion was used as a characteristic feature. Trichoplax were observed to migrate to areas with low density of electric field lines, which are far from electrodes or behind them. Animals from old culture were less sensitive to electrical stimulus. H2 strain was more reactive than H1 strain and especially than H13 strain; it demonstrated stronger physiological responses at frequencies of 2 Hz and 2 kHz with a voltage of 50 mV. Motion patterns and animal morphology depended on the duration of rectangular stimulation pulses, their number, amplitude, and frequency. Effects observed varied over a wide range: from direct or stochastic migration of animals to the anode or the cathode or away from it to their immobility, an increase of optical density around and in the middle of Trichoplax plate, and finally to Trichoplax folding and detach from the substrate. Additional experiments on Trichoplax sp. H2 with pulse duration of 35 ms and pulse delay of 1 ms to 10 s showed that the fraction of paralyzed animals increased up to 80 % with minimum delay. Nevertheless, in the presence of amlodipine with a concentration of 25 nM, almost all Trichoplax remained fast-moving for several minutes despite exposure to voltage waves. Experimental animals showed a total discoordination of motion and could not leave an “electrode trap”, when amlodipine with a concentration of 250 nM was used. Further, Trichoplax plate became rigid, which appeared in animal shape invariability during motion. Finally, amlodipine with a concentration of 50 μM caused a rapid folding of animal plate-like body into a pan in the ventral-dorsal direction and subsequent dissociation of Trichoplax plate into individual cells. In general, the electrical exposure applied demonstrated a cumulative but a reversible physiological effect, which, as expected, is associated with activity of voltage-gated calcium channels. Amlodipine at high concentration (50 μM) caused Trichoplax disintegration; at moderate concentration (250 nM), it disrupted the propagation of activation waves that led to discoordination of animal motion; at low concentration (25 nM), it prevented an electric shock.
Collapse
|
28
|
Brückner A, Parker J. Molecular evolution of gland cell types and chemical interactions in animals. ACTA ACUST UNITED AC 2020; 223:223/Suppl_1/jeb211938. [PMID: 32034048 DOI: 10.1242/jeb.211938] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Across the Metazoa, the emergence of new ecological interactions has been enabled by the repeated evolution of exocrine glands. Specialized glands have arisen recurrently and with great frequency, even in single genera or species, transforming how animals interact with their environment through trophic resource exploitation, pheromonal communication, chemical defense and parental care. The widespread convergent evolution of animal glands implies that exocrine secretory cells are a hotspot of metazoan cell type innovation. Each evolutionary origin of a novel gland involves a process of 'gland cell type assembly': the stitching together of unique biosynthesis pathways; coordinated changes in secretory systems to enable efficient chemical release; and transcriptional deployment of these machineries into cells constituting the gland. This molecular evolutionary process influences what types of compound a given species is capable of secreting, and, consequently, the kinds of ecological interactions that species can display. Here, we discuss what is known about the evolutionary assembly of gland cell types and propose a framework for how it may happen. We posit the existence of 'terminal selector' transcription factors that program gland function via regulatory recruitment of biosynthetic enzymes and secretory proteins. We suggest ancestral enzymes are initially co-opted into the novel gland, fostering pleiotropic conflict that drives enzyme duplication. This process has yielded the observed pattern of modular, gland-specific biosynthesis pathways optimized for manufacturing specific secretions. We anticipate that single-cell technologies and gene editing methods applicable in diverse species will transform the study of animal chemical interactions, revealing how gland cell types are assembled and functionally configured at a molecular level.
Collapse
Affiliation(s)
- Adrian Brückner
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 E. California Boulevard, Pasadena, CA 91125, USA
| | - Joseph Parker
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 E. California Boulevard, Pasadena, CA 91125, USA
| |
Collapse
|
29
|
Marinković M, Berger J, Jékely G. Neuronal coordination of motile cilia in locomotion and feeding. Philos Trans R Soc Lond B Biol Sci 2019; 375:20190165. [PMID: 31884921 PMCID: PMC7017327 DOI: 10.1098/rstb.2019.0165] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Efficient ciliary locomotion and transport require the coordination of motile cilia. Short-range coordination of ciliary beats can occur by biophysical mechanisms. Long-range coordination across large or disjointed ciliated fields often requires nervous system control and innervation of ciliated cells by ciliomotor neurons. The neuronal control of cilia is best understood in invertebrate ciliated microswimmers, but similar mechanisms may operate in the vertebrate body. Here, we review how the study of aquatic invertebrates contributed to our understanding of the neuronal control of cilia. We summarize the anatomy of ciliomotor systems and the physiological mechanisms that can alter ciliary activity. We also discuss the most well-characterized ciliomotor system, that of the larval annelid Platynereis. Here, pacemaker neurons drive the rhythmic activation of cholinergic and serotonergic ciliomotor neurons to induce ciliary arrests and beating. The Platynereis ciliomotor neurons form a distinct part of the larval nervous system. Similar ciliomotor systems likely operate in other ciliated larvae, such as mollusc veligers. We discuss the possible ancestry and conservation of ciliomotor circuits and highlight how comparative experimental approaches could contribute to a better understanding of the evolution and function of ciliary systems. This article is part of the Theo Murphy meeting issue ‘Unity and diversity of cilia in locomotion and transport’.
Collapse
Affiliation(s)
- Milena Marinković
- Living Systems Institute, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Jürgen Berger
- Max Planck Institute for Developmental Biology, 72076 Tübingen, Germany
| | - Gáspár Jékely
- Living Systems Institute, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| |
Collapse
|
30
|
Abstract
During sleep, animals do not eat, reproduce or forage. Sleeping animals are vulnerable to predation. Yet, the persistence of sleep despite evolutionary pressures, and the deleterious effects of sleep deprivation, indicate that sleep serves a function or functions that cannot easily be bypassed. Recent research demonstrates sleep to be phylogenetically far more pervasive than previously appreciated; it is possible that the very first animals slept. Here, we give an overview of sleep across various species, with the aim of determining its original purpose. Sleep exists in animals without cephalized nervous systems and can be influenced by non-neuronal signals, including those associated with metabolic rhythms. Together, these observations support the notion that sleep serves metabolic functions in neural and non-neural tissues.
Collapse
Affiliation(s)
- Ron C Anafi
- Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Center for Sleep and Circadian Neurobiology and the Program for Chronobiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Matthew S Kayser
- Center for Sleep and Circadian Neurobiology and the Program for Chronobiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Department of Psychiatry and Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - David M Raizen
- Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA. .,Center for Sleep and Circadian Neurobiology and the Program for Chronobiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA. .,Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| |
Collapse
|
31
|
Kamm K, Osigus HJ, Stadler PF, DeSalle R, Schierwater B. Genome analyses of a placozoan rickettsial endosymbiont show a combination of mutualistic and parasitic traits. Sci Rep 2019; 9:17561. [PMID: 31772223 PMCID: PMC6879607 DOI: 10.1038/s41598-019-54037-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 10/25/2019] [Indexed: 12/16/2022] Open
Abstract
Symbiotic relationships between eukaryotic hosts and bacteria range from parasitism to mutualism and may deeply influence both partners' fitness. The presence of intracellular bacteria in the metazoan phylum Placozoa has been reported several times, but without any knowledge about the nature of this relationship and possible implications for the placozoan holobiont. This information may be of crucial significance since little is known about placozoan ecology and how different species adapt to different environmental conditions, despite being almost invariable at the morphological level. We here report on the novel genome of the rickettsial endosymbiont of Trichoplax sp. H2 (strain "Panama"). The combination of eliminated and retained metabolic pathways of the bacterium indicates a potential for a mutualistic as well as for a parasitic relationship, whose outcome could depend on the environmental context. In particular we show that the endosymbiont is dependent on the host for growth and reproduction and that the latter could benefit from a supply with essential amino acids and important cofactors. These findings call for further studies to clarify the actual benefit for the placozoan host and to investigate a possible role of the endosymbiont for ecological separation between placozoan species.
Collapse
Affiliation(s)
- Kai Kamm
- University of Veterinary Medicine Hannover, Foundation, Institute of Animal Ecology, Bünteweg 17d, D-30559, Hannover, Germany.
| | - Hans-Jürgen Osigus
- University of Veterinary Medicine Hannover, Foundation, Institute of Animal Ecology, Bünteweg 17d, D-30559, Hannover, Germany
| | - Peter F Stadler
- Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, University of Leipzig, Härtelstraße 16-18, D-04107, Leipzig, Germany
| | - Rob DeSalle
- Sackler Institute for Comparative Genomics and Division of Invertebrate Zoology, American Museum of Natural History, New York, New York, USA
| | - Bernd Schierwater
- University of Veterinary Medicine Hannover, Foundation, Institute of Animal Ecology, Bünteweg 17d, D-30559, Hannover, Germany. .,Sackler Institute for Comparative Genomics and Division of Invertebrate Zoology, American Museum of Natural History, New York, New York, USA.
| |
Collapse
|
32
|
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.
Collapse
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
| |
Collapse
|
33
|
Paulin MG, Cahill‐Lane J. Events in Early Nervous System Evolution. Top Cogn Sci 2019; 13:25-44. [DOI: 10.1111/tops.12461] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 09/09/2019] [Accepted: 09/09/2019] [Indexed: 12/20/2022]
|
34
|
Elkhatib W, Smith CL, Senatore A. A Na + leak channel cloned from Trichoplax adhaerens extends extracellular pH and Ca 2+ sensing for the DEG/ENaC family close to the base of Metazoa. J Biol Chem 2019; 294:16320-16336. [PMID: 31527080 PMCID: PMC6827283 DOI: 10.1074/jbc.ra119.010542] [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] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 09/11/2019] [Indexed: 12/22/2022] Open
Abstract
Acid-sensitive ion channels belonging to the degenerin/epithelial sodium channel (DEG/ENaC) family activate in response to extracellular protons and are considered unique to deuterostomes. However, sensitivity to pH/protons is more widespread, where, for example, human ENaC Na+ leak channels are potentiated and mouse BASIC and Caenorhabditis elegans ACD-1 Na+ leak channels are blocked by extracellular protons. For many DEG/ENaC channels, extracellular Ca2+ ions modulate gating, and in some cases, the binding of protons and Ca2+ is interdependent. Here, we functionally characterize a DEG/ENaC channel from the early-diverging animal Trichoplax adhaerens, TadNaC6, that conducts Na+-selective leak currents in vitro sensitive to blockade by both extracellular protons and Ca2+. We determine that proton block is enhanced in low external Ca2+ concentration, whereas calcium block is enhanced in low external proton concentration, indicative of competitive binding of these two ligands to extracellular sites of the channel protein. TadNaC6 lacks most determinant residues for proton and Ca2+ sensitivity in other DEG/ENaC channels, and a mutation of one conserved residue (S353A) associated with Ca2+ block in rodent BASIC channels instead affected proton sensitivity, all indicative of independent evolution of H+ and Ca2+ sensitivity. Strikingly, TadNaC6 was potently activated by the general DEG/ENaC channel blocker amiloride, a rare feature only reported for the acid-activated channel ASIC3. The sequence and structural divergence of TadNaC6, coupled with its noncanonical functional features, provide unique opportunities for probing the proton, Ca2+, and amiloride regulation of DEG/ENaC channels and insight into the possible core-gating features of ancestral ion channels.
Collapse
Affiliation(s)
- Wassim Elkhatib
- Department of Biology, University of Toronto Mississauga, Mississauga, Ontario L5L 1C6, Canada
| | - Carolyn L Smith
- NINDS, National Institutes of Health, Bethesda, Maryland 20892
| | - Adriano Senatore
- Department of Biology, University of Toronto Mississauga, Mississauga, Ontario L5L 1C6, Canada
| |
Collapse
|
35
|
Steinmetz PRH. A non-bilaterian perspective on the development and evolution of animal digestive systems. Cell Tissue Res 2019; 377:321-339. [PMID: 31388768 PMCID: PMC6733828 DOI: 10.1007/s00441-019-03075-x] [Citation(s) in RCA: 19] [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: 03/22/2019] [Accepted: 07/08/2019] [Indexed: 12/14/2022]
Abstract
Digestive systems and extracellular digestion are key animal features, but their emergence during early animal evolution is currently poorly understood. As the last common ancestor of non-bilaterian animal groups (sponges, ctenophores, placozoans and cnidarians) dates back to the beginning of animal life, their study and comparison provides important insights into the early evolution of digestive systems and functions. Here, I have compiled an overview of the development and cell biology of digestive tissues in non-bilaterian animals. I will highlight the fundamental differences between extracellular and intracellular digestive processes, and how these are distributed among animals. Cnidarians (e.g. sea anemones, corals, jellyfish), the phylogenetic outgroup of bilaterians (e.g. vertebrates, flies, annelids), occupy a key position to reconstruct the evolution of bilaterian gut evolution. A major focus will therefore lie on the development and cell biology of digestive tissues in cnidarians, especially sea anemones, and how they compare to bilaterian gut tissues. In that context, I will also review how a recent study on the gastrula fate map of the sea anemone Nematostella vectensis challenges our long-standing conceptions on the evolution of cnidarian and bilaterian germ layers and guts.
Collapse
Affiliation(s)
- Patrick R H Steinmetz
- Sars International Centre for Marine Molecular Biology, University of Bergen, Thormøhlensgt. 55, 5006, Bergen, Norway.
| |
Collapse
|
36
|
Mayorova TD, Hammar K, Winters CA, Reese TS, Smith CL. The ventral epithelium of Trichoplax adhaerens deploys in distinct patterns cells that secrete digestive enzymes, mucus or diverse neuropeptides. Biol Open 2019; 8:bio045674. [PMID: 31366453 PMCID: PMC6737977 DOI: 10.1242/bio.045674] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 07/23/2019] [Indexed: 01/11/2023] Open
Abstract
The disk-shaped millimeter-sized marine animal, Trichoplax adhaerens, is notable because of its small number of cell types and primitive mode of feeding. It glides on substrates propelled by beating cilia on its lower surface and periodically pauses to feed on underlying microorganisms, which it digests externally. Here, a combination of advanced electron and light microscopic techniques are used to take a closer look at its secretory cell types and their roles in locomotion and feeding. We identify digestive enzymes in lipophils, a cell type implicated in external digestion and distributed uniformly throughout the ventral epithelium except for a narrow zone near its edge. We find three morphologically distinct types of gland cell. The most prevalent contains and secretes mucus, which is shown to be involved in adhesion and gliding. Half of the mucocytes are arrayed in a tight row around the edge of the ventral epithelium while the rest are scattered further inside, in the region containing lipophils. The secretory granules in mucocytes at the edge label with an antibody against a neuropeptide that was reported to arrest ciliary beating during feeding. A second type of gland cell is arrayed in a narrow row just inside the row of mucocytes while a third is located more centrally. Our maps of the positions of the structurally distinct secretory cell types provide a foundation for further characterization of the multiple peptidergic cell types in Trichoplax and the microscopic techniques we introduce provide tools for carrying out these studies.
Collapse
Affiliation(s)
- Tatiana D Mayorova
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 49 Convent Drive, Bethesda, MD 20892, USA
| | - Katherine Hammar
- Central Microscopy Facility, Marine Biological Laboratory, 7 MBL Street, Woods Hole, MA 02543, USA
| | - Christine A Winters
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 49 Convent Drive, Bethesda, MD 20892, USA
| | - Thomas S Reese
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 49 Convent Drive, Bethesda, MD 20892, USA
| | - Carolyn L Smith
- Light Imaging Facility, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 35 Convent Drive, Bethesda, MD 20892, USA
| |
Collapse
|
37
|
Smith CL, Mayorova TD. Insights into the evolution of digestive systems from studies of Trichoplax adhaerens. Cell Tissue Res 2019; 377:353-367. [PMID: 31270610 DOI: 10.1007/s00441-019-03057-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 06/09/2019] [Indexed: 01/01/2023]
Abstract
Trichoplax, a member of the phylum Placozoa, is a tiny ciliated marine animal that glides on surfaces feeding on algae and cyanobacteria. It stands out from other animals in that it lacks an internal digestive system and, instead, digests food trapped under its lower surface. Here we review recent work on the phenotypes of its six cell types and their roles in digestion and feeding behavior. Phylogenomic analyses place Placozoa as sister to Eumetazoa, the clade that includes Cnidaria and Bilateria. Comparing the phenotypes of cells in Trichoplax to those of cells in the digestive epithelia of Eumetazoa allows us to make inferences about the cell types and mode of feeding of their ancestors. From our increasingly mechanistic understanding of feeding in Trichoplax, we get a glimpse into how primitive animals may have hunted and consumed food prior to the evolution of neurons, muscles, and internal digestive systems.
Collapse
Affiliation(s)
- Carolyn L Smith
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA.
| | - Tatiana D Mayorova
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA
| |
Collapse
|
38
|
Nielsen C. Early animal evolution: a morphologist's view. ROYAL SOCIETY OPEN SCIENCE 2019; 6:190638. [PMID: 31417759 PMCID: PMC6689584 DOI: 10.1098/rsos.190638] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 07/04/2019] [Indexed: 05/15/2023]
Abstract
Two hypotheses for the early radiation of the metazoans are vividly discussed in recent phylogenomic studies, the 'Porifera-first' hypothesis, which places the poriferans as the sister group of all other metazoans, and the 'Ctenophora-first' hypothesis, which places the ctenophores as the sister group to all other metazoans. It has been suggested that an analysis of morphological characters (including specific molecules) could throw additional light on the controversy, and this is the aim of this paper. Both hypotheses imply independent evolution of nervous systems in Planulozoa and Ctenophora. The Porifera-first hypothesis implies no homoplasies or losses of major characters. The Ctenophora-first hypothesis shows no important synapomorphies of Porifera, Planulozoa and Placozoa. It implies either independent evolution, in Planulozoa and Ctenophora, of a new digestive system with a gut with extracellular digestion, which enables feeding on larger organisms, or the subsequent loss of this new gut in the Poriferans (and the re-evolution of the collar complex). The major losses implied in the Ctenophora-first theory show absolutely no adaptational advantages. Thus, morphology gives very strong support for the Porifera-first hypothesis.
Collapse
Affiliation(s)
- Claus Nielsen
- The Natural History Museum of Denmark, University of Copenhagen, Zoological Museum, Universitetsparken 15, DK-2100 Copenhagen, Denmark
| |
Collapse
|
39
|
Gruber-Vodicka HR, Leisch N, Kleiner M, Hinzke T, Liebeke M, McFall-Ngai M, Hadfield MG, Dubilier N. Two intracellular and cell type-specific bacterial symbionts in the placozoan Trichoplax H2. Nat Microbiol 2019; 4:1465-1474. [PMID: 31182796 PMCID: PMC6784892 DOI: 10.1038/s41564-019-0475-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Accepted: 04/26/2019] [Indexed: 02/02/2023]
Abstract
Placozoa is an enigmatic phylum of simple, microscopic, marine metazoans1,2. Although intracellular bacteria have been found in all members of this phylum, almost nothing is known about their identity, location and interactions with their host3–6. We used metagenomic and metatranscriptomic sequencing of single host individuals, plus metaproteomic and imaging analyses, to show that the placozoan Trichoplax sp. H2 lives in symbiosis with two intracellular bacteria. One symbiont forms an undescribed genus in the Midichloriaceae (Rickettsiales)7,8 and has a genomic repertoire similar to that of rickettsial parasites9,10, but does not seem to express key genes for energy parasitism. Correlative image analyses and three-dimensional electron tomography revealed that this symbiont resides in the rough endoplasmic reticulum of its host’s internal fibre cells. The second symbiont belongs to the Margulisbacteria, a phylum without cultured representatives and not known to form intracellular associations11–13. This symbiont lives in the ventral epithelial cells of Trichoplax, probably metabolizes algal lipids digested by its host and has the capacity to supplement the placozoan’s nutrition. Our study shows that one of the simplest animals has evolved highly specific and intimate associations with symbiotic, intracellular bacteria and highlights that symbioses can provide access to otherwise elusive microbial dark matter. Using a multi-omics approach, together with imaging analyses, the authors characterize the two intracellular bacterial symbionts of Trichoplax, one of the simplest animals.
Collapse
Affiliation(s)
| | - Nikolaus Leisch
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Manuel Kleiner
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC, USA
| | - Tjorven Hinzke
- Department of Pharmaceutical Biotechnology, Institute of Pharmacy, University of Greifswald, Greifswald, Germany.,Institute of Marine Biotechnology, Greifswald, Germany.,Department of Geoscience, University of Calgary, Calgary, Alberta, Canada
| | - Manuel Liebeke
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Margaret McFall-Ngai
- Kewalo Marine Laboratory, Pacific Biosciences Research Center, University of Hawai'i at Mānoa, Honolulu, HI, USA
| | - Michael G Hadfield
- Kewalo Marine Laboratory, Pacific Biosciences Research Center, University of Hawai'i at Mānoa, Honolulu, HI, USA.
| | - Nicole Dubilier
- Max Planck Institute for Marine Microbiology, Bremen, Germany.
| |
Collapse
|
40
|
DuBuc TQ, Ryan JF, Martindale MQ. "Dorsal-Ventral" Genes Are Part of an Ancient Axial Patterning System: Evidence from Trichoplax adhaerens (Placozoa). Mol Biol Evol 2019; 36:966-973. [PMID: 30726986 PMCID: PMC6501881 DOI: 10.1093/molbev/msz025] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Placozoa are a morphologically simplistic group of marine animals found globally in tropical and subtropical environments. They consist of two named species, Trichoplax adhaerens and more recently Hoilungia hongkongensis, both with roughly six morphologically distinct cell types. With a sequenced genome, a limited number of cell types, and a simple flattened morphology, Trichoplax is an ideal model organism from which to explore the biology of an animal with a cellular complexity analagous to that of the earliest animals. Using a new approach for identification of gene expression patterns, this research looks at the relationship of Chordin/TgfΒ signaling and the axial patterning system of Placozoa. Our results suggest that placozoans have an oral-aboral axis similar to cnidarians and that the parahoxozoan ancestor (common ancestor of Placozoa and Cnidaria) was likely radially symmetric.
Collapse
Affiliation(s)
- Timothy Q DuBuc
- Whitney Lab for Marine Bioscience and the Department of Biology, University of Florida, St. Augustine, FL
- Kewalo Marine Laboratory and the Department of Biology, University of Hawaii, Manoa, Honolulu, HI
- Centre for Chromosome Biology, Bioscience Building, National University of Ireland Galway, Galway, Ireland
| | - Joseph F Ryan
- Whitney Lab for Marine Bioscience and the Department of Biology, University of Florida, St. Augustine, FL
| | - Mark Q Martindale
- Whitney Lab for Marine Bioscience and the Department of Biology, University of Florida, St. Augustine, FL
| |
Collapse
|
41
|
Albertini MC, Fraternale D, Semprucci F, Cecchini S, Colomba M, Rocchi MBL, Sisti D, Di Giacomo B, Mari M, Sabatini L, Cesaroni L, Balsamo M, Guidi L. Bioeffects of Prunus spinosa L. fruit ethanol extract on reproduction and phenotypic plasticity of Trichoplax adhaerens Schulze, 1883 (Placozoa). PeerJ 2019; 7:e6789. [PMID: 31024778 PMCID: PMC6475577 DOI: 10.7717/peerj.6789] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2018] [Accepted: 03/14/2019] [Indexed: 12/17/2022] Open
Abstract
The aim of this work was to test and analyse the bioeffects of Prunus spinosa L. (Rosacaee) fruit ethanol extract on Trichoplax adhaerens Schulze, 1883 (Placozoa) laboratory cultures which—for the first time—were employed as in vivo biological model to assess the bioactivity of a natural extract. The ethanol extract of P. spinosa was administrated during a 46 day experimental period; ultrastructural (by optical, confocal, TEM and SEM microscopy) and morphometric analyses indicated that treated Trichoplax adhaerens showed significant differences in viability, reproductive modalities, body shape and colour with respect to the control group. Finally, P. spinosa bioactive compounds seem to exert profound protective effects on T. adhaerens reproduction and phenotype. Our results may support additional investigations related to other bioactive compounds properties useful for nutraceutical preparations to be used as food supplements.
Collapse
Affiliation(s)
| | - Daniele Fraternale
- Department of Biomolecular Sciences, University of Urbino, Urbino, Pesaro-Urbino, Italia
| | - Federica Semprucci
- Department of Biomolecular Sciences, University of Urbino, Urbino, Pesaro-Urbino, Italia
| | - Silvio Cecchini
- Department of Biomolecular Sciences, University of Urbino, Urbino, Pesaro-Urbino, Italia
| | - Mariastella Colomba
- Department of Biomolecular Sciences, University of Urbino, Urbino, Pesaro-Urbino, Italia
| | - Marco B L Rocchi
- Department of Biomolecular Sciences, University of Urbino, Urbino, Pesaro-Urbino, Italia
| | - Davide Sisti
- Department of Biomolecular Sciences, University of Urbino, Urbino, Pesaro-Urbino, Italia
| | - Barbara Di Giacomo
- Department of Biomolecular Sciences, University of Urbino, Urbino, Pesaro-Urbino, Italia
| | - Michele Mari
- Department of Biomolecular Sciences, University of Urbino, Urbino, Pesaro-Urbino, Italia
| | - Luigia Sabatini
- Department of Biomolecular Sciences, University of Urbino, Urbino, Pesaro-Urbino, Italia
| | - Lucia Cesaroni
- Department of Biomolecular Sciences, University of Urbino, Urbino, Pesaro-Urbino, Italia
| | - Maria Balsamo
- Department of Biomolecular Sciences, University of Urbino, Urbino, Pesaro-Urbino, Italia
| | - Loretta Guidi
- Department of Biomolecular Sciences, University of Urbino, Urbino, Pesaro-Urbino, Italia
| |
Collapse
|
42
|
Coherent directed movement toward food modeled in Trichoplax, a ciliated animal lacking a nervous system. Proc Natl Acad Sci U S A 2019; 116:8901-8908. [PMID: 30979806 PMCID: PMC6500112 DOI: 10.1073/pnas.1815655116] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Trichoplax adhaerens is a small, ciliated marine animal that glides on surfaces grazing upon algae, which it digests externally. It has no muscles or nervous system and only six cell types, all but two of which are embedded in its epithelium. The epithelial cells are joined by apical adherens junctions; neither tight junctions nor gap junctions are present. Monociliated epithelial cells on the lower surface propel gliding. The cilia beat regularly, but asynchronously, and transiently contact the substrate with each stroke. The animal moves in random directions in the absence of food. We show here that it exhibits chemotaxis, moving preferentially toward algae embedded in a disk of agar. We present a mathematical model to explain how coherent, directional movements could arise from the collective actions of a set of ciliated epithelial cells, each independently sensing and responding to a chemoattractant gradient. The model incorporates realistic values for viscoelastic properties of cells and produces coordinated movements and changes in body shape that resemble the actual movements of the animal. The model demonstrates that an animal can move coherently in search of food without any need for chemical signaling between cells and introduces a different approach to modeling behavior in primitive multicellular organisms.
Collapse
|
43
|
Churgin MA, Szuperak M, Davis KC, Raizen DM, Fang-Yen C, Kayser MS. Quantitative imaging of sleep behavior in Caenorhabditis elegans and larval Drosophila melanogaster. Nat Protoc 2019; 14:1455-1488. [PMID: 30953041 DOI: 10.1038/s41596-019-0146-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 01/29/2019] [Indexed: 01/04/2023]
Abstract
Sleep is nearly universal among animals, yet remains poorly understood. Recent work has leveraged simple model organisms, such as Caenorhabditis elegans and Drosophila melanogaster larvae, to investigate the genetic and neural bases of sleep. However, manual methods of recording sleep behavior in these systems are labor intensive and low in throughput. To address these limitations, we developed methods for quantitative imaging of individual animals cultivated in custom microfabricated multiwell substrates, and used them to elucidate molecular mechanisms underlying sleep. Here, we describe the steps necessary to design, produce, and image these plates, as well as analyze the resulting behavioral data. We also describe approaches for experimentally manipulating sleep. Following these procedures, after ~2 h of experimental preparation, we are able to simultaneously image 24 C. elegans from the second larval stage to adult stages or 20 Drosophila larvae during the second instar life stage at a spatial resolution of 10 or 27 µm, respectively. Although this system has been optimized to measure activity and quiescence in Caenorhabditis larvae and adults and in Drosophila larvae, it can also be used to assess other behaviors over short or long periods. Moreover, with minor modifications, it can be adapted for the behavioral monitoring of a wide range of small animals.
Collapse
Affiliation(s)
- Matthew A Churgin
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, USA
| | - Milan Szuperak
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Kristen C Davis
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Center for Excellence in Environmental Toxicology (CEET), Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - David M Raizen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Chronobiology Program, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Center for Sleep and Circadian Neurobiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Christopher Fang-Yen
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, USA.,Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Matthew S Kayser
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA. .,Chronobiology Program, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA. .,Center for Sleep and Circadian Neurobiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA. .,Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| |
Collapse
|
44
|
Abstract
Animals have evolved different foraging strategies in which some animals forage independently and others forage in groups. The evolution of social feeding does not necessarily require cooperation; social feeding can be a beneficial individual-level strategy if it provides mutualistic benefits, for example though increasing the efficiency of resource extraction or processing. We found that Trichoplax adhaerens, the simplest multicellular animal ever described, engages in social feeding behavior. T. adhaerens lacks muscle tissue, nervous and digestive systems - yet is capable of aggregating and forming groups of closely connected individuals who collectively feed. The tight physical interactions between the animals are transitory and appear to serve the goal of staying connected to neighbors during the external digestion of algae when enzymes are released on the biofilm and nutrients are absorbed through the ventral epithelium. We found that T. adhaerens are more likely to engage in social feeding when the concentrations of algae are high - both in a semi-natural conditions and in vitro. It is surprising that T. adhaerens - an organism without a nervous system - is able to engage in this social feeding behavior. Whether this behavior is cooperative is still an open question. Nevertheless, the social feeding behavior of T. adhaerens, an early multicellular animal, suggests that sociality may have played an important role in the early evolution of animals. It also suggests that T. adhaerens could be used as a simple model organism for exploring questions regarding ecology and sociobiology.
Collapse
Affiliation(s)
- Angelo Fortunato
- Biodesign Center for Biocomputing, Security and Society, Arizona State University
| | - Athena Aktipis
- Biodesign Center for Biocomputing, Security and Society, Arizona State University.,Department of Psychology, Arizona State University
| |
Collapse
|
45
|
High Cell Diversity and Complex Peptidergic Signaling Underlie Placozoan Behavior. Curr Biol 2018; 28:3495-3501.e2. [DOI: 10.1016/j.cub.2018.08.067] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Revised: 07/20/2018] [Accepted: 08/31/2018] [Indexed: 12/17/2022]
|
46
|
Armon S, Bull MS, Aranda-Diaz A, Prakash M. Ultrafast epithelial contractions provide insights into contraction speed limits and tissue integrity. Proc Natl Acad Sci U S A 2018; 115:E10333-E10341. [PMID: 30309963 PMCID: PMC6217427 DOI: 10.1073/pnas.1802934115] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
By definition of multicellularity, all animals need to keep their cells attached and intact, despite internal and external forces. Cohesion between epithelial cells provides this key feature. To better understand fundamental limits of this cohesion, we study the epithelium mechanics of an ultrathin (∼25 μm) primitive marine animal Trichoplax adhaerens, composed essentially of two flat epithelial layers. With no known extracellular matrix and no nerves or muscles, T. adhaerens has been claimed to be the "simplest known living animal," yet is still capable of coordinated locomotion and behavior. Here we report the discovery of the fastest epithelial cellular contractions known in any metazoan, to be found in T. adhaerens dorsal epithelium (50% shrinkage of apical cell area within one second, at least an order of magnitude faster than other known examples). Live imaging reveals emergent contractile patterns that are mostly sporadic single-cell events, but also include propagating contraction waves across the tissue. We show that cell contraction speed can be explained by current models of nonmuscle actin-myosin bundles without load, while the tissue architecture and unique mechanical properties are softening the tissue, minimizing the load on a contracting cell. We propose a hypothesis, in which the physiological role of the contraction dynamics is to resist external stresses while avoiding tissue rupture ("active cohesion"), a concept that can be further applied to engineering of active materials.
Collapse
Affiliation(s)
- Shahaf Armon
- Department of Bioengineering, Stanford University, Stanford, CA 94305
| | | | | | - Manu Prakash
- Department of Bioengineering, Stanford University, Stanford, CA 94305;
- Chan Zuckerberg Biohub, San Francisco, CA 94158
| |
Collapse
|
47
|
Laumer CE, Gruber-Vodicka H, Hadfield MG, Pearse VB, Riesgo A, Marioni JC, Giribet G. Support for a clade of Placozoa and Cnidaria in genes with minimal compositional bias. eLife 2018; 7:e36278. [PMID: 30373720 PMCID: PMC6277202 DOI: 10.7554/elife.36278] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 10/11/2018] [Indexed: 12/22/2022] Open
Abstract
The phylogenetic placement of the morphologically simple placozoans is crucial to understanding the evolution of complex animal traits. Here, we examine the influence of adding new genomes from placozoans to a large dataset designed to study the deepest splits in the animal phylogeny. Using site-heterogeneous substitution models, we show that it is possible to obtain strong support, in both amino acid and reduced-alphabet matrices, for either a sister-group relationship between Cnidaria and Placozoa, or for Cnidaria and Bilateria as seen in most published work to date, depending on the orthologues selected to construct the matrix. We demonstrate that a majority of genes show evidence of compositional heterogeneity, and that support for the Cnidaria + Bilateria clade can be assigned to this source of systematic error. In interpreting these results, we caution against a peremptory reading of placozoans as secondarily reduced forms of little relevance to broader discussions of early animal evolution.
Collapse
Affiliation(s)
- Christopher E Laumer
- Wellcome Trust Sanger InstituteHinxtonUnited Kingdom
- European Molecular Biology Laboratories-European Bioinformatics InstituteHinxtonUnited Kingdom
| | | | - Michael G Hadfield
- Kewalo Marine LaboratoryPacific Biosciences Research Center and the University of Hawaii-ManoaHonoluluUnited States
| | - Vicki B Pearse
- Institute of Marine SciencesUniversity of CaliforniaSanta CruzUnited States
| | - Ana Riesgo
- Invertebrate Division, Life Sciences DepartmentThe Natural History MuseumLondonUnited Kingdom
| | - John C Marioni
- Wellcome Trust Sanger InstituteHinxtonUnited Kingdom
- European Molecular Biology Laboratories-European Bioinformatics InstituteHinxtonUnited Kingdom
- Cancer Research UK Cambridge InstituteUniversity of CambridgeCambridgeUnited Kingdom
| | - Gonzalo Giribet
- Museum of Comparative Zoology, Department of Organismic and Evolutionary BiologyHarvard UniversityCambridgeUnited States
| |
Collapse
|
48
|
Miyazawa H, Nakano H. Multiple surveys employing a new sample-processing protocol reveal the genetic diversity of placozoans in Japan. Ecol Evol 2018; 8:2407-2417. [PMID: 29531663 PMCID: PMC5838039 DOI: 10.1002/ece3.3861] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 12/19/2017] [Accepted: 01/02/2018] [Indexed: 11/08/2022] Open
Abstract
Placozoans, flat free-living marine invertebrates, possess an extremely simple bauplan lacking neurons and muscle cells and represent one of the earliest-branching metazoan phyla. They are widely distributed from temperate to tropical oceans. Based on mitochondrial 16S rRNA sequences, 19 haplotypes forming seven distinct clades have been reported in placozoans to date. In Japan, placozoans have been found at nine locations, but 16S genotyping has been performed at only two of these locations. Here, we propose a new processing protocol, "ethanol-treated substrate sampling," for collecting placozoans from natural environments. We also report the collection of placozoans from three new locations, the islands of Shikine-jima, Chichi-jima, and Haha-jima, and we present the distribution of the 16S haplotypes of placozoans in Japan. Multiple surveys conducted at multiple locations yielded five haplotypes that were not reported previously, revealing high genetic diversity in Japan, especially at Shimoda and Shikine-jima Island. The observed geographic distribution patterns were different among haplotypes; some were widely distributed, while others were sampled only from a single location. However, samplings conducted on different dates at the same sites yielded different haplotypes, suggesting that placozoans of a given haplotype do not inhabit the same site constantly throughout the year. Continued sampling efforts conducted during all seasons at multiple locations worldwide and the development of molecular markers within the haplotypes are needed to reveal the geographic distribution pattern and dispersal history of placozoans in greater detail.
Collapse
Affiliation(s)
- Hideyuki Miyazawa
- Shimoda Marine Research CenterUniversity of TsukubaShimodaShizuokaJapan
| | - Hiroaki Nakano
- Shimoda Marine Research CenterUniversity of TsukubaShimodaShizuokaJapan
| |
Collapse
|
49
|
Mayorova TD, Smith CL, Hammar K, Winters CA, Pivovarova NB, Aronova MA, Leapman RD, Reese TS. Cells containing aragonite crystals mediate responses to gravity in Trichoplax adhaerens (Placozoa), an animal lacking neurons and synapses. PLoS One 2018; 13:e0190905. [PMID: 29342202 PMCID: PMC5771587 DOI: 10.1371/journal.pone.0190905] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 12/21/2017] [Indexed: 11/23/2022] Open
Abstract
Trichoplax adhaerens has only six cell types. The function as well as the structure of crystal cells, the least numerous cell type, presented an enigma. Crystal cells are arrayed around the perimeter of the animal and each contains a birefringent crystal. Crystal cells resemble lithocytes in other animals so we looked for evidence they are gravity sensors. Confocal microscopy showed that their cup-shaped nuclei are oriented toward the edge of the animal, and that the crystal shifts downward under the influence of gravity. Some animals spontaneously lack crystal cells and these animals behaved differently upon being tilted vertically than animals with a typical number of crystal cells. EM revealed crystal cell contacts with fiber cells and epithelial cells but these contacts lacked features of synapses. EM spectroscopic analyses showed that crystals consist of the aragonite form of calcium carbonate. We thus provide behavioral evidence that Trichoplax are able to sense gravity, and that crystal cells are likely to be their gravity receptors. Moreover, because placozoans are thought to have evolved during Ediacaran or Cryogenian eras associated with aragonite seas, and their crystals are made of aragonite, they may have acquired gravity sensors during this early era.
Collapse
Affiliation(s)
- Tatiana D. Mayorova
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, United States of America
- Laboratory of Developmental Neurobiology, Koltzov Institute of Developmental Biology, Russian Academy of Science, Moscow, Russia
| | - Carolyn L. Smith
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Katherine Hammar
- Central Microscopy Facility, Marine Biological Laboratory, Woods Hole, MA, United States of America
| | - Christine A. Winters
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Natalia B. Pivovarova
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Maria A. Aronova
- Laboratory of Cellular Imaging and Macromolecular Biophysics, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Rockville Pike, Bethesda, Maryland, United States of America
| | - Richard D. Leapman
- Laboratory of Cellular Imaging and Macromolecular Biophysics, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Rockville Pike, Bethesda, Maryland, United States of America
| | - Thomas S. Reese
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, United States of America
| |
Collapse
|
50
|
Misra M, Audoly B, Shvartsman SY. Complex structures from patterned cell sheets. Philos Trans R Soc Lond B Biol Sci 2017; 372:rstb.2015.0515. [PMID: 28348251 DOI: 10.1098/rstb.2015.0515] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/26/2016] [Indexed: 12/30/2022] Open
Abstract
The formation of three-dimensional structures from patterned epithelial sheets plays a key role in tissue morphogenesis. An important class of morphogenetic mechanisms relies on the spatio-temporal control of apical cell contractility, which can result in the localized bending of cell sheets and in-plane cell rearrangements. We have recently proposed a modified vertex model that can be used to systematically explore the connection between the two-dimensional patterns of cell properties and the emerging three-dimensional structures. Here we review the proposed modelling framework and illustrate it through the computational analysis of the vertex model that captures the salient features of the formation of the dorsal appendages during Drosophila oogenesis.This article is part of the themed issue 'Systems morphodynamics: understanding the development of tissue hardware'.
Collapse
Affiliation(s)
- M Misra
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA.,Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| | - B Audoly
- LMS, École Polytechnique, CNRS, Université Paris-Saclay, 91128 Palaiseau, France
| | - S Y Shvartsman
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA .,Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| |
Collapse
|