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Picciani N, Kerlin JR, Sierra N, Swafford AJM, Ramirez MD, Roberts NG, Cannon JT, Daly M, Oakley TH. Prolific Origination of Eyes in Cnidaria with Co-option of Non-visual Opsins. Curr Biol 2018; 28:2413-2419.e4. [PMID: 30033336 DOI: 10.1016/j.cub.2018.05.055] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 03/26/2018] [Accepted: 05/17/2018] [Indexed: 11/15/2022]
Abstract
Animal eyes vary considerably in morphology and complexity and are thus ideal for understanding the evolution of complex biological traits [1]. While eyes evolved many times in bilaterian animals with elaborate nervous systems, image-forming and simpler eyes also exist in cnidarians, which are ancient non-bilaterians with neural nets and regions with condensed neurons to process information. How often eyes of varying complexity, including image-forming eyes, arose in animals with such simple neural circuitry remains obscure. Here, we produced large-scale phylogenies of Cnidaria and their photosensitive proteins and coupled them with an extensive literature search on eyes and light-sensing behavior to show that cnidarian eyes originated at least eight times, with complex, lensed-eyes having a history separate from other eye types. Compiled data show widespread light-sensing behavior in eyeless cnidarians, and comparative analyses support ancestors without eyes that already sensed light with dispersed photoreceptor cells. The history of expression of photoreceptive opsin proteins supports the inference of distinct eye origins via separate co-option of different non-visual opsin paralogs into eyes. Overall, our results show eyes evolved repeatedly from ancestral photoreceptor cells in non-bilaterian animals with simple nervous systems, co-opting existing precursors, similar to what occurred in Bilateria. Our study underscores the potential for multiple, evolutionarily distinct visual systems even in animals with simple nervous systems.
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Affiliation(s)
- Natasha Picciani
- Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, Santa Barbara, CA 93106, USA.
| | - Jamie R Kerlin
- Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Noemie Sierra
- Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Andrew J M Swafford
- Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - M Desmond Ramirez
- Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Nickellaus G Roberts
- Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Johanna T Cannon
- Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Marymegan Daly
- Department of Evolution, Ecology, and Organismal Biology, Ohio State University, Columbus, OH 43210, USA
| | - Todd H Oakley
- Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, Santa Barbara, CA 93106, USA.
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102
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Gupta A, Kaur H. 18S and 28S rDNA identity and phylogeny of two novel myxosporeans infecting gills of cyprinid carps inhabiting a cold water wetland in northern India. Microb Pathog 2018; 120:97-108. [DOI: 10.1016/j.micpath.2018.04.042] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Revised: 04/16/2018] [Accepted: 04/23/2018] [Indexed: 10/17/2022]
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103
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Animal origins and the Tonian Earth system. Emerg Top Life Sci 2018; 2:289-298. [PMID: 32412615 DOI: 10.1042/etls20170160] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 05/23/2018] [Accepted: 05/25/2018] [Indexed: 01/30/2023]
Abstract
The Neoproterozoic Era (1000-541 million years ago, Ma) was characterized by dramatic environmental and evolutionary change, including at least two episodes of extensive, low-latitude glaciation, potential changes in the redox structure of the global ocean, and the origin and diversification of animal life. How these different events related to one another remains an active area of research, particularly how these environmental changes influenced, and were influenced by, the earliest evolution of animals. Animal multicellularity is estimated to have evolved in the Tonian Period (1000-720 Ma) and represents one of at least six independent acquisitions of complex multicellularity, characterized by cellular differentiation, three-dimensional body plans, and active nutrient transport. Compared with the other instances of complex multicellularity, animals represent the only clade to have evolved from wall-less, phagotrophic flagellates, which likely placed unique cytological and trophic constraints on the evolution of animal multicellularity. Here, we compare recent molecular clock estimates with compilations of the chromium isotope, micropaleontological, and organic biomarker records, suggesting that, as of now, the origin of animals was not obviously correlated to any environmental-ecological change in the Tonian Period. This lack of correlation is consistent with the idea that the evolution of animal multicellularity was primarily dictated by internal, developmental constraints and occurred independently of the known environmental-ecological changes that characterized the Neoproterozoic Era.
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104
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Myxozoans: Ancient metazoan parasites find a home in phylum Cnidaria. ZOOLOGY 2018; 129:66-68. [PMID: 30170750 DOI: 10.1016/j.zool.2018.06.005] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 06/18/2018] [Accepted: 06/20/2018] [Indexed: 01/02/2023]
Abstract
Myxozoans are endoparasites with complex life cycles that alternate between invertebrate and vertebrate hosts. Though considered protozoans for over 150 years, they are now recognized as metazoans, given their multicellularity and ultrastructural features. In recognition of synapomorphies and cnidarian-specific genes, myxozoans were placed recently within the phylum Cnidaria. Although they have lost genetic and structural complexity on the path to parasitism, myxozoans have retained characteristic cnidarian cnidocysts, but use them for initiating host infection. Myxozoans represent at least 20% of phylum Cnidaria, but as a result of rapid evolution, extensive diversification and host specialization, they are probably at least as diverse as their free-living relatives. The ability of myxozoans to infect freshwater, marine and terrestrial hosts implies that Cnidaria are no longer constrained to the aquatic environment.
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105
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Patra S, Bartošová-Sojková P, Pecková H, Fiala I, Eszterbauer E, Holzer AS. Biodiversity and host-parasite cophylogeny of Sphaerospora (sensu stricto) (Cnidaria: Myxozoa). Parasit Vectors 2018; 11:347. [PMID: 29903034 PMCID: PMC6002976 DOI: 10.1186/s13071-018-2863-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Accepted: 04/23/2018] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND Myxozoa are extremely diverse microscopic parasites belonging to the Cnidaria. Their life-cycles alternate between vertebrate and invertebrate hosts, predominantly in aquatic habitats. Members of the phylogenetically well-defined Sphaerospora (sensu stricto) clade predominantly infect the urinary system of marine and freshwater fishes and amphibians. Sphaerosporids are extraordinary due to their extremely long and unique insertions in the variable regions of their 18S and 28S rDNA genes and due to the formation of motile proliferative stages in the hosts' blood. To date, DNA sequences of only 19 species have been obtained and information on the patterns responsible for their phylogenetic clustering is limited. METHODS We screened 549 fish kidney samples from fish of various geographical locations, mainly in central Europe, to investigate sphaerosporid biodiversity microscopically and by 18S rDNA sequences. We performed multiple phylogenetic analyses to explore phylogenetic relationships and evolutionary trends within the Sphaerospora (s.s.) clade, by matching host and habitat features to the resultant 18S rDNA trees. The apparent co-clustering of species from related fish hosts inspired us to further investigate host-parasite co-diversification, using tree-based (CoRE-PA) and distance-based (ParaFit) methods. RESULTS Our study considerably increased the number of 18S rDNA sequence data for Sphaerospora (s.s.) by sequencing 17 new taxa. Eight new species are described and one species (Sphaerospora diminuta Li & Desser, 1985) is redescribed, accompanied by sufficient morphological data. Phylogenetic analyses showed that sphaerosporids cluster according to their vertebrate host order and habitat, but not according to geography. Cophylogenetic analyses revealed a significant congruence between the phylogenetic trees of sphaerosporids and of their vertebrate hosts and identified Cypriniformes as a host group of multiple parasite lineages and with high parasite diversity. CONCLUSIONS This study significantly contributed to our knowledge of the biodiversity and evolutionary history of the members of the Sphaerospora (s.s.) clade. The presence of two separate phylogenetic lineages likely indicates independent historical host entries, and the remarkable overlap of the larger clade with vertebrate phylogeny suggests important coevolutionary adaptations. Hyperdiversification of sphaerosporids in cypriniform hosts, which have undergone considerable radiations themselves, points to host-driven diversification.
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Affiliation(s)
- Sneha Patra
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 37005 České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, 37005 České Budějovice, Czech Republic
| | - Pavla Bartošová-Sojková
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 37005 České Budějovice, Czech Republic
| | - Hana Pecková
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 37005 České Budějovice, Czech Republic
| | - Ivan Fiala
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 37005 České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, 37005 České Budějovice, Czech Republic
| | - Edit Eszterbauer
- Institute for Veterinary Medical Research, Centre for Agricultural Research, Budapest, H-1143 Hungary
| | - Astrid S. Holzer
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 37005 České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, 37005 České Budějovice, Czech Republic
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106
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Hernandez AM, Ryan JF. Horizontally transferred genes in the ctenophore Mnemiopsis leidyi. PeerJ 2018; 6:e5067. [PMID: 29922518 PMCID: PMC6005172 DOI: 10.7717/peerj.5067] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 06/04/2018] [Indexed: 12/16/2022] Open
Abstract
Horizontal gene transfer (HGT) has had major impacts on the biology of a wide range of organisms from antibiotic resistance in bacteria to adaptations to herbivory in arthropods. A growing body of literature shows that HGT between non-animals and animals is more commonplace than previously thought. In this study, we present a thorough investigation of HGT in the ctenophore Mnemiopsis leidyi. We applied tests of phylogenetic incongruence to identify nine genes that were likely transferred horizontally early in ctenophore evolution from bacteria and non-metazoan eukaryotes. All but one of these HGTs (an uncharacterized protein) are homologous to characterized enzymes, supporting previous observations that genes encoding enzymes are more likely to be retained after HGT events. We found that the majority of these nine horizontally transferred genes were expressed during development, suggesting that they are active and play a role in the biology of M. leidyi. This is the first report of HGT in ctenophores, and contributes to an ever-growing literature on the prevalence of genetic information flowing between non-animals and animals.
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Affiliation(s)
- Alexandra M Hernandez
- Whitney Laboratory for Marine Bioscience, St. Augustine, FL, USA.,Department of Biology, University of Florida, Gainesville, FL, USA
| | - Joseph F Ryan
- Whitney Laboratory for Marine Bioscience, St. Augustine, FL, USA.,Department of Biology, University of Florida, Gainesville, FL, USA
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107
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Richter DJ, Fozouni P, Eisen MB, King N. Gene family innovation, conservation and loss on the animal stem lineage. eLife 2018; 7:34226. [PMID: 29848444 PMCID: PMC6040629 DOI: 10.7554/elife.34226] [Citation(s) in RCA: 111] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2017] [Accepted: 05/26/2018] [Indexed: 02/06/2023] Open
Abstract
Choanoflagellates, the closest living relatives of animals, can provide unique insights into the changes in gene content that preceded the origin of animals. However, only two choanoflagellate genomes are currently available, providing poor coverage of their diversity. We sequenced transcriptomes of 19 additional choanoflagellate species to produce a comprehensive reconstruction of the gains and losses that shaped the ancestral animal gene repertoire. We identified ~1944 gene families that originated on the animal stem lineage, of which only 39 are conserved across all animals in our study. In addition, ~372 gene families previously thought to be animal-specific, including Notch, Delta, and homologs of the animal Toll-like receptor genes, instead evolved prior to the animal-choanoflagellate divergence. Our findings contribute to an increasingly detailed portrait of the gene families that defined the biology of the Urmetazoan and that may underpin core features of extant animals. All animals, from sea sponges and reef-building corals to elephants and humans, share a single common ancestor that lived over half a billion years ago. This single-celled predecessor evolved the ability to develop into a creature made up of many cells with specialized jobs. Reconstructing the steps in this evolutionary process has been difficult because the earliest animals were soft-bodied and microscopic and did not leave behind fossils that scientists can study. Though their bodies have since disintegrated, many of the instructions for building the first animals live on in genes that were passed on to life forms that still exist. Scientists are trying to retrace those genes back to the first animal by comparing the genomes of living animals with their closest relatives, the choanoflagellates. Choanoflagellates are single-celled, colony-forming organisms that live in waters around the world. Comparisons with choanoflagellates may help scientists identify which genes were necessary to help animals evolve and diversify into so many different species. So far, 1,000 animal and two choanoflagellate genomes have been sequenced. But the gene repertoires of most species of choanoflagellates have yet to be analyzed. Now, Richter et al. have cataloged the genes of 19 more species of choanoflagellates. This added information allowed them to recreate the likely gene set of the first animal and to identify genetic changes that occurred during animal evolution. The analyses showed that modern animals lost about a quarter of the genes present in their last common ancestor with choanoflagellates and gained an equal number of new genes. Richter et al. identified several dozen core animal genes that were gained and subsequently preserved throughout animal evolution. Many of these are necessary so that an embryo can develop properly, but the precise roles of some core genes remain a mystery. Most other genes that emerged in the first animals have been lost in at least one living animal. The study of Richter et al. also showed that some very important genes in animals, including genes essential for early development and genes that help the immune system detect pathogens, predate animals. These key genes trace back to animals’ last common ancestor with choanoflagellates and may have evolved new roles in animals.
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Affiliation(s)
- Daniel J Richter
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States.,Sorbonne Universités, UPMC Univ Paris 06, CNRS UMR 7144, Adaptation et Diversité en Milieu Marin, Équipe EPEP, Station Biologique de Roscoff, Roscoff, France
| | - Parinaz Fozouni
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States.,Medical Scientist Training Program, Biomedical Sciences Graduate Program, University of California, San Francisco, San Francisco, United States.,Gladstone Institutes, San Francisco, United States
| | - Michael B Eisen
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States
| | - Nicole King
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States
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108
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Identification of a new myxosporean parasite Thelohanellus indiana n. sp. (Myxosporea: Myxobolidae) isolated from three major organs of goldfish, Carassius auratus L. highlighted with its morphological and SSU rDNA sequence based molecular description. Microb Pathog 2018; 122:191-199. [PMID: 29803847 DOI: 10.1016/j.micpath.2018.05.038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 05/18/2018] [Accepted: 05/23/2018] [Indexed: 11/23/2022]
Abstract
Fish mortality and poor growth in surviving fish contribute substantial losses to the ornamental fish farms of India and revealed an infection of a new myxosporidian parasite Thelohanellus indiana n. sp. which has become one of the most important limiting factors for successful aquaculture management. The parasite infects Carassius auratus, an Indian goldfish, described on the basis of myxospores morphology and amplification of a part of 18 S rDNA gene. Three major attaching site of fish body have been explored for showing the location of attachment for the parasites. The whitish cysts of the parasites are about 2.5-3.5 mm contains large amount of lemon shaped mature myxospores measuring 12.1-15.2 (13.8) × 7.5-8.8 (8) μm. A single round or elliptical polar capsule located only at the anterior pole of the spore having 6.2-7.2 (6.8) × 3.3-4.7 (4.0) μm in diameter. The morphological characters have been assessed by both the light and scanning electron microscope. The most differentiating feature from closely related species was carried out by morpho-taxonomic affinities with previously described species which are tremendously supported by molecular taxonomy by partial sequencing of the 18 S rDNA gene resulted in a total of 2101 bp fragment of newly obtained SSU rRNA gene sequence of the new species which exhibit 79-91% homogeneity with other closely related species available in GenBank. The BLAST search of Thelohanellus sp. did not matches with any available sequences in GenBank and the phylogenetic analysis revealed that the novel species were sister to T. habibpuri and T. caudatus, in the Thelohanellus clade and form a closest neighboring branch as a subclade in phylogenetic tree from which the new Thelohanellus parasite is being placed. Both the branches are originating from monophyletic clade that are strongly supported by bootstrap values which indicate clearly about independent position of T. indiana n. sp.
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109
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Saha M, Bandyopadhyay P. Morphological and ssrDNA sequence based molecular characterization of a novel Thelohanellus species (Myxosporea: Myxobolidae) infecting the fins of Goldfish, Carassius auratus L. with special reference to its histopathological alteration. Acta Trop 2018; 181:25-34. [PMID: 29407849 DOI: 10.1016/j.actatropica.2018.01.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 01/26/2018] [Indexed: 11/25/2022]
Abstract
A new species of myxozoan, Thelohanellus goldi n. sp. is described using morphological and molecular data, parasitizing the fin filaments from 18 of 25 host specimens (72.5%) of Carassius auratus collected from different ornamental fish farms of India. Mature spore of the new species were oval to spherical in frontal view having rounded posterior ends and tapering anterior end measures 8.7-10.26 (9.50) × 4.10-7.89 (5.84) μm. The single large polar capsule, round to oval in shape but slightly pointed at the anterior end measuring 4.91-7.63 (5.60) × 2.3-3.1 (2.96) μm and located just below the anterior end of the spore. Polar filament only at distal end with 5-6 loose coils. The most differentiating feature from closely related species was carried out by morpho-taxonomic affinities with previously described species which are tremendously supported by molecular taxonomy by partial sequencing of the 18S rDNA gene resulted in a total of 2124 bp fragment of newly obtained small subunit ribosomal RNA gene sequence of the new species which Exhibit 93-95% homogeneity with other closely related species available in GenBank. The BLAST search and high genetic diversity of distance matrix of Myxobolus sp. did not properly match with any available sequences in GenBank and make sister clade with Thelohanellus caudatus and Thelohanellus habibpuri in the Thelohanellus clade including most of Thelohanellus spp. The study of evolutionary history enables us to understand the evolution of modern species and supports some uncertain topologies which are being presented regarding the morphometric analysis. The severity of myxozoan infection has been assessed in this article by observing the histopathological changes of fins of the C. auratus along with the diversity, distribution and taxonomic description of the new Thelohanellus species with their new host and locality records.
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110
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Kayal E, Bentlage B, Sabrina Pankey M, Ohdera AH, Medina M, Plachetzki DC, Collins AG, Ryan JF. Phylogenomics provides a robust topology of the major cnidarian lineages and insights on the origins of key organismal traits. BMC Evol Biol 2018. [PMCID: PMC5932825 DOI: 10.1186/s12862-018-1142-0] [Citation(s) in RCA: 114] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Background The phylogeny of Cnidaria has been a source of debate for decades, during which nearly all-possible relationships among the major lineages have been proposed. The ecological success of Cnidaria is predicated on several fascinating organismal innovations including stinging cells, symbiosis, colonial body plans and elaborate life histories. However, understanding the origins and subsequent diversification of these traits remains difficult due to persistent uncertainty surrounding the evolutionary relationships within Cnidaria. While recent phylogenomic studies have advanced our knowledge of the cnidarian tree of life, no analysis to date has included genome-scale data for each major cnidarian lineage. Results Here we describe a well-supported hypothesis for cnidarian phylogeny based on phylogenomic analyses of new and existing genome-scale data that includes representatives of all cnidarian classes. Our results are robust to alternative modes of phylogenetic estimation and phylogenomic dataset construction. We show that two popular phylogenomic matrix construction pipelines yield profoundly different datasets, both in the identities and in the functional classes of the loci they include, but resolve the same topology. We then leverage our phylogenetic resolution of Cnidaria to understand the character histories of several critical organismal traits. Ancestral state reconstruction analyses based on our phylogeny establish several notable organismal transitions in the evolutionary history of Cnidaria and depict the ancestral cnidarian as a solitary, non-symbiotic polyp that lacked a medusa stage. In addition, Bayes factor tests strongly suggest that symbiosis has evolved multiple times independently across the cnidarian radiation. Conclusions Cnidaria have experienced more than 600 million years of independent evolution and in the process generated an array of organismal innovations. Our results add significant clarification on the cnidarian tree of life and the histories of some of these innovations. Further, we confirm the existence of Acraspeda (staurozoans plus scyphozoans and cubozoans), thus reviving an evolutionary hypothesis put forward more than a century ago. Electronic supplementary material The online version of this article (10.1186/s12862-018-1142-0) contains supplementary material, which is available to authorized users.
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111
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Sasson DA, Jacquez AA, Ryan JF. The ctenophore Mnemiopsis leidyi regulates egg production via conspecific communication. BMC Ecol 2018; 18:12. [PMID: 29576018 PMCID: PMC5868061 DOI: 10.1186/s12898-018-0169-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2017] [Accepted: 03/15/2018] [Indexed: 11/10/2022] Open
Abstract
Background Communication between individuals of the same species is an important aspect of mating and reproduction in most animals. In simultaneously hermaphroditic species with the ability to self-fertilize, communication with conspecifics can be essential to avoid inbreeding depression. One such behavioral adaptation observed in some simultaneous hermaphrodites is gamete trading. This behavior involves individual hermaphrodites in pairs alternating between reproducing as the male and female, and, as such, necessarily requires communication and coordination between mates. Little is known about communication in ctenophores and conspecific communication has not been described in this group; however, our previous work suggested that the ctenophore Mnemiopsis leidyi might engage in gamete trading. We tested for this possibility by constructing divided arenas (both sealed and permeable) that allowed us to measure individual egg output for paired M. leidyi. Results We found that, when not allowed to interact, size-matched individuals produced similar numbers of eggs on each side of the arena. However, if allowed to interact and exchange water, size-matched pairs produce significantly different numbers of eggs on each side of the arena, suggesting that these pairs use chemical communication to modulate reproduction in the presence of conspecifics as would be expected in gamete trading. Conclusion This finding presents exciting new possibilities for future investigations into the nature of signaling in M. leidyi. Furthermore, this first evidence of conspecific communication in Ctenophora, a group that branched off from the rest of animals more than 600 million years ago, has significant implications for the signaling ability of the last common ancestor of all animals. Electronic supplementary material The online version of this article (10.1186/s12898-018-0169-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Daniel A Sasson
- Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL, USA.,Department of Biology, Saint Louis University, Saint Louis, MO, USA
| | - Anya A Jacquez
- Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL, USA.,Department of Biology, Lewis & Clark College, Portland, OR, USA
| | - Joseph F Ryan
- Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL, USA. .,Department of Biology, University of Florida, Gainesville, FL, USA.
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112
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Morphological features and molecular phylogeny of Hoferellus azevedoi n. sp. (Myxozoa: Myxobilatidae) found in Chaetobranchus flavescens Heckel, 1840 (Teleostei: Cichlidae) from Marajó Island, northern Brazil. Parasitol Res 2018; 117:1087-1093. [PMID: 29435717 DOI: 10.1007/s00436-018-5785-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 01/24/2018] [Indexed: 10/18/2022]
Abstract
Hoferellus azevedoi n. sp. was found in the urinary bladder of Chaetobranchus flavescens Heckel, 1840 from the Arari River on Marajó Island in Pará, Brazil. This is the first record of a species of the genus Hoferellus in a host from the Brazilian Amazon region. The new species has disporous and polysporous plasmodia, which vary in size and shape, with some being found adhered to the epithelium of the urinary bladder, and others floating in the liquid. The mature spores are sub-spherical in the sutural view, with a number of peripheral projections around the whole surface of the spore. In the sutural view, the spores are 5.3 ± 0.2 (5.2-5.6) μm in length and 7.0 ± 0.7 (6.3-7.7) μm in width, with two piriform polar capsules of equal size, 2.5 ± 0.2 (2.3-2.8) μm long and 1.8 ± 0.2 (1.6-2.0) μm wide. Based on a partial (1312 bps) sequence of the SSU rDNA gene, Hoferellus azevedoi n. sp. was distinguished from all the other myxozoan species deposited in GenBank. Phylogenetically, based on Bayesian inference and p-distances, the new species was allocated to the "Freshwater Urinary-Bladder" clade, together with other myxozoan parasites of the excretory system. Based on the morphological data, supported by the partial sequence of the SSU rDNA gene, we describe a new species of myxozoan, Hoferellus azevedoi n. sp.
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113
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Myxobolus okamurae sp. nov. (Myxosporea: Myxozoa) causing severe gill myxoboliosis in the cyprinid Labeo bata in a cold water wetland, Punjab (India). Microb Pathog 2018; 115:86-92. [DOI: 10.1016/j.micpath.2017.12.041] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2017] [Revised: 12/12/2017] [Accepted: 12/14/2017] [Indexed: 11/18/2022]
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114
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Heim NA, Payne JL, Finnegan S, Knope ML, Kowalewski M, Lyons SK, McShea DW, Novack-Gottshall PM, Smith FA, Wang SC. Hierarchical complexity and the size limits of life. Proc Biol Sci 2018. [PMID: 28637850 DOI: 10.1098/rspb.2017.1039] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Over the past 3.8 billion years, the maximum size of life has increased by approximately 18 orders of magnitude. Much of this increase is associated with two major evolutionary innovations: the evolution of eukaryotes from prokaryotic cells approximately 1.9 billion years ago (Ga), and multicellular life diversifying from unicellular ancestors approximately 0.6 Ga. However, the quantitative relationship between organismal size and structural complexity remains poorly documented. We assessed this relationship using a comprehensive dataset that includes organismal size and level of biological complexity for 11 172 extant genera. We find that the distributions of sizes within complexity levels are unimodal, whereas the aggregate distribution is multimodal. Moreover, both the mean size and the range of size occupied increases with each additional level of complexity. Increases in size range are non-symmetric: the maximum organismal size increases more than the minimum. The majority of the observed increase in organismal size over the history of life on the Earth is accounted for by two discrete jumps in complexity rather than evolutionary trends within levels of complexity. Our results provide quantitative support for an evolutionary expansion away from a minimal size constraint and suggest a fundamental rescaling of the constraints on minimal and maximal size as biological complexity increases.
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Affiliation(s)
- Noel A Heim
- Department of Geological Sciences, Stanford University, Stanford, CA 94305, USA
| | - Jonathan L Payne
- Department of Geological Sciences, Stanford University, Stanford, CA 94305, USA
| | - Seth Finnegan
- Department of Integrative Biology, University of California, Berkeley, CA 94720, USA
| | - Matthew L Knope
- Department of Biology, University of Hawaii, Hilo, HI 96720, USA
| | - Michał Kowalewski
- Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA
| | - S Kathleen Lyons
- School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, NE 68588, USA
| | - Daniel W McShea
- Department of Biology, Duke University, Durham, NC 27708, USA
| | | | - Felisa A Smith
- Department of Biology, University of New Mexico, Albuquerque, NM 87131, USA
| | - Steve C Wang
- Department of Mathematics and Statistics, Swarthmore College, Swarthmore, PA 19081, USA
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115
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Whelan NV, Halanych KM. Who Let the CAT Out of the Bag? Accurately Dealing with Substitutional Heterogeneity in Phylogenomic Analyses. Syst Biol 2018; 66:232-255. [PMID: 27633354 DOI: 10.1093/sysbio/syw084] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2015] [Accepted: 09/04/2016] [Indexed: 11/14/2022] Open
Abstract
As phylogenetic datasets have increased in size, site-heterogeneous substitution models such as CAT-F81 and CAT-GTR have been advocated in favor of other models because they purportedly suppress long-branch attraction (LBA). These models are two of the most commonly used models in phylogenomics, and they have been applied to a variety of taxa, ranging from Drosophila to land plants. However, many arguments in favor of CAT models have been based on tenuous assumptions about the true phylogeny, rather than rigorous testing with known trees via simulation. Moreover, CAT models have not been compared to other approaches for handling substitutional heterogeneity such as data partitioning with site-homogeneous substitution models. We simulated amino acid sequence datasets with substitutional heterogeneity on a variety of tree shapes including those susceptible to LBA. Data were analyzed with both CAT models and partitioning to explore model performance; in total over 670,000 CPU hours were used, of which over 97% was spent running analyses with CAT models. In many cases, all models recovered branching patterns that were identical to the known tree. However, CAT-F81 consistently performed worse than other models in inferring the correct branching patterns, and both CAT models often overestimated substitutional heterogeneity. Additionally, reanalysis of two empirical metazoan datasets supports the notion that CAT-F81 tends to recover less accurate trees than data partitioning and CAT-GTR. Given these results, we conclude that partitioning and CAT-GTR perform similarly in recovering accurate branching patterns. However, computation time can be orders of magnitude less for data partitioning, with commonly used implementations of CAT-GTR often failing to reach completion in a reasonable time frame (i.e., for Bayesian analyses to converge). Practices such as removing constant sites and parsimony uninformative characters, or using CAT-F81 when CAT-GTR is deemed too computationally expensive, cannot be logically justified. Given clear problems with CAT-F81, phylogenies previously inferred with this model should be reassessed. [Data partitioning; phylogenomics, simulation, site-heterogeneity, substitution models.].
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Affiliation(s)
- Nathan V Whelan
- Department of Biological Sciences, Molette Biology Laboratory for Environmental and Climate Change Studies, Auburn University, 101 Life Sciences Building, Auburn, AL 36849, USA
| | - Kenneth M Halanych
- Department of Biological Sciences, Molette Biology Laboratory for Environmental and Climate Change Studies, Auburn University, 101 Life Sciences Building, Auburn, AL 36849, USA
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116
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Braden LM, Rasmussen KJ, Purcell SL, Ellis L, Mahony A, Cho S, Whyte SK, Jones SRM, Fast MD. Acquired Protective Immunity in Atlantic Salmon Salmo salar against the Myxozoan Kudoa thyrsites Involves Induction of MHIIβ + CD83 + Antigen-Presenting Cells. Infect Immun 2018; 86:e00556-17. [PMID: 28993459 PMCID: PMC5736826 DOI: 10.1128/iai.00556-17] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 10/03/2017] [Indexed: 12/15/2022] Open
Abstract
The histozoic myxozoan parasite Kudoa thyrsites causes postmortem myoliquefaction and is responsible for economic losses to salmon aquaculture in the Pacific Northwest. Despite its importance, little is known about the host-parasite relationship, including the host response to infection. The present work sought to characterize the immune response in Atlantic salmon during infection, recovery, and reexposure to K. thyrsites After exposure to infective seawater, infected and uninfected smolts were sampled three times over 4,275 degree-days. Histological analysis revealed infection severity decreased over time in exposed fish, while in controls there was no evidence of infection. Following a secondary exposure of all fish, severity of infection in the controls was similar to that measured in exposed fish at the first sampling time but was significantly reduced in reexposed fish, suggesting the acquisition of protective immunity. Using immunohistochemistry, we detected a population of MHIIβ+ cells in infected muscle that followed a pattern of abundance concordant with parasite prevalence. Infiltration of these cells into infected myocytes preceded destruction of the plasmodium and dissemination of myxospores. Dual labeling indicated a majority of these cells were CD83+/MHIIβ+ Using reverse transcription-quantitative PCR, we detected significant induction of cellular effectors, including macrophage/dendritic cells (mhii/cd83/mcsf), B cells (igm/igt), and cytotoxic T cells (cd8/nkl), in the musculature of infected fish. These data support a role for cellular effectors such as antigen-presenting cells (monocyte/macrophage and dendritic cells) along with B and T cells in the acquired protective immune response of Atlantic salmon against K. thyrsites.
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Affiliation(s)
- Laura M Braden
- Hoplite Laboratory, Department of Pathology & Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, Prince Edward Island, Canada
| | - Karina J Rasmussen
- Department of Cancer and Inflammation Research, University of Southern Denmark, Odense, Denmark
| | - Sara L Purcell
- Hoplite Laboratory, Department of Pathology & Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, Prince Edward Island, Canada
| | - Lauren Ellis
- Hoplite Laboratory, Department of Pathology & Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, Prince Edward Island, Canada
| | - Amelia Mahony
- Pacific Biological Station, Fisheries and Oceans Canada, Nanaimo, BC, Canada
| | - Steven Cho
- Pacific Biological Station, Fisheries and Oceans Canada, Nanaimo, BC, Canada
| | - Shona K Whyte
- Hoplite Laboratory, Department of Pathology & Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, Prince Edward Island, Canada
| | - Simon R M Jones
- Pacific Biological Station, Fisheries and Oceans Canada, Nanaimo, BC, Canada
| | - Mark D Fast
- Hoplite Laboratory, Department of Pathology & Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, Prince Edward Island, Canada
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117
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Sasson DA, Ryan JF. A reconstruction of sexual modes throughout animal evolution. BMC Evol Biol 2017; 17:242. [PMID: 29207942 PMCID: PMC5717846 DOI: 10.1186/s12862-017-1071-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Accepted: 11/15/2017] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Although most extant animals have separate sexes, simultaneous hermaphrodites can be found in lineages throughout the animal kingdom. However, the sexual modes of key ancestral nodes including the last common ancestor (LCA) of all animals remain unclear. Without these data, it is difficult to infer the reproductive-state transitions that occurred early in animal evolution, and thus a broad understanding of the evolution of animal reproduction remains elusive. In this study, we use a composite phylogeny from four previously published studies, two alternative topologies (ctenophores or sponges as sister to the rest of animals), and multiple phylogenetic approaches to conduct the most extensive analysis to date of the evolution of animal sexual modes. RESULTS Our analyses clarify the sexual mode of many ancestral animal nodes and allow for sound inferences of modal transitions that have occurred in animal history. Our results also indicate that the transition from separate sexes to hermaphroditism has been more common in animal history than the reverse. CONCLUSIONS These results provide the most complete view of the evolution of animal sexual modes to date and provide a framework for future inquiries into the correlation of these transitions with genes, behaviors, and physiology. These results also suggest that mutations promoting hermaphroditism have historically been more likely to invade gonochoristic populations than vice versa.
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Affiliation(s)
- Daniel A Sasson
- Whitney Laboratory for Marine Bioscience, University of Florida, 9505 Ocean Shore Blvd, St. Augustine, FL, USA
- Department of Biology, University of Florida, Gainesville, FL, USA
| | - Joseph F Ryan
- Whitney Laboratory for Marine Bioscience, University of Florida, 9505 Ocean Shore Blvd, St. Augustine, FL, USA.
- Department of Biology, University of Florida, Gainesville, FL, USA.
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118
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Feuda R, Dohrmann M, Pett W, Philippe H, Rota-Stabelli O, Lartillot N, Wörheide G, Pisani D. Improved Modeling of Compositional Heterogeneity Supports Sponges as Sister to All Other Animals. Curr Biol 2017; 27:3864-3870.e4. [DOI: 10.1016/j.cub.2017.11.008] [Citation(s) in RCA: 138] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 09/19/2017] [Accepted: 11/02/2017] [Indexed: 10/18/2022]
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119
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Cavalier-Smith T. Origin of animal multicellularity: precursors, causes, consequences-the choanoflagellate/sponge transition, neurogenesis and the Cambrian explosion. Philos Trans R Soc Lond B Biol Sci 2017; 372:rstb.2015.0476. [PMID: 27994119 PMCID: PMC5182410 DOI: 10.1098/rstb.2015.0476] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/05/2016] [Indexed: 02/07/2023] Open
Abstract
Evolving multicellularity is easy, especially in phototrophs and osmotrophs whose multicells feed like unicells. Evolving animals was much harder and unique; probably only one pathway via benthic ‘zoophytes’ with pelagic ciliated larvae allowed trophic continuity from phagocytic protozoa to gut-endowed animals. Choanoflagellate protozoa produced sponges. Converting sponge flask cells mediating larval settling to synaptically controlled nematocysts arguably made Cnidaria. I replace Haeckel's gastraea theory by a sponge/coelenterate/bilaterian pathway: Placozoa, hydrozoan diploblasty and ctenophores were secondary; stem anthozoan developmental mutations arguably independently generated coelomate bilateria and ctenophores. I emphasize animal origin's conceptual aspects (selective, developmental) related to feeding modes, cell structure, phylogeny of related protozoa, sequence evidence, ecology and palaeontology. Epithelia and connective tissue could evolve only by compensating for dramatically lower feeding efficiency that differentiation into non-choanocytes entails. Consequentially, larger bodies enabled filtering more water for bacterial food and harbouring photosynthetic bacteria, together adding more food than cell differentiation sacrificed. A hypothetical presponge of sessile triploblastic sheets (connective tissue sandwiched between two choanocyte epithelia) evolved oogamy through selection for larger dispersive ciliated larvae to accelerate benthic trophic competence and overgrowing protozoan competitors. Extinct Vendozoa might be elaborations of this organismal grade with choanocyte-bearing epithelia, before poriferan water channels and cnidarian gut/nematocysts/synapses evolved. This article is part of the themed issue ‘Evo-devo in the genomics era, and the origins of morphological diversity’.
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120
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Schenkelaars Q, Pratlong M, Kodjabachian L, Fierro-Constain L, Vacelet J, Le Bivic A, Renard E, Borchiellini C. Animal multicellularity and polarity without Wnt signaling. Sci Rep 2017; 7:15383. [PMID: 29133828 PMCID: PMC5684314 DOI: 10.1038/s41598-017-15557-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 10/30/2017] [Indexed: 12/24/2022] Open
Abstract
Acquisition of multicellularity is a central event in the evolution of Eukaryota. Strikingly, animal multicellularity coincides with the emergence of three intercellular communication pathways - Notch, TGF-β and Wnt - all considered as hallmarks of metazoan development. By investigating Oopsacas minuta and Aphrocallistes vastus, we show here that the emergence of a syncytium and plugged junctions in glass sponges coincides with the loss of essential components of the Wnt signaling (i.e. Wntless, Wnt ligands and Disheveled), whereas core components of the TGF-β and Notch modules appear unaffected. This suggests that Wnt signaling is not essential for cell differentiation, polarity and morphogenesis in glass sponges. Beyond providing a comparative study of key developmental toolkits, we define here the first case of a metazoan phylum that maintained a level of complexity similar to its relatives despite molecular degeneration of Wnt pathways.
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Affiliation(s)
- Quentin Schenkelaars
- Aix Marseille Université, CNRS, IRD, IMBE UMR 7263, Avignon Université, Institut Méditerranéen de Biodiversité et d'Ecologie marine et continentale, Station Marine d'Endoume, Marseille, France.
- Department of Genetics and Evolution, University of Geneva, Sciences III, 30 Quai Ernest Ansermet, CH-1211, Geneva 4, Switzerland.
| | - Marine Pratlong
- Aix Marseille Université, CNRS, IRD, IMBE UMR 7263, Avignon Université, Institut Méditerranéen de Biodiversité et d'Ecologie marine et continentale, Station Marine d'Endoume, Marseille, France
- Aix Marseille Université, CNRS, Centrale Marseille, I2M, Equipe Evolution Biologique et Modélisation, Marseille, France
| | - Laurent Kodjabachian
- Aix Marseille Université, CNRS, Institute of Developmental Biology of Marseille (IBDM), case 907, 13288, Marseille cedex 09, France
| | - Laura Fierro-Constain
- Aix Marseille Université, CNRS, IRD, IMBE UMR 7263, Avignon Université, Institut Méditerranéen de Biodiversité et d'Ecologie marine et continentale, Station Marine d'Endoume, Marseille, France
| | - Jean Vacelet
- Aix Marseille Université, CNRS, IRD, IMBE UMR 7263, Avignon Université, Institut Méditerranéen de Biodiversité et d'Ecologie marine et continentale, Station Marine d'Endoume, Marseille, France
| | - André Le Bivic
- Aix Marseille Université, CNRS, Institute of Developmental Biology of Marseille (IBDM), case 907, 13288, Marseille cedex 09, France.
| | - Emmanuelle Renard
- Aix Marseille Université, CNRS, IRD, IMBE UMR 7263, Avignon Université, Institut Méditerranéen de Biodiversité et d'Ecologie marine et continentale, Station Marine d'Endoume, Marseille, France
| | - Carole Borchiellini
- Aix Marseille Université, CNRS, IRD, IMBE UMR 7263, Avignon Université, Institut Méditerranéen de Biodiversité et d'Ecologie marine et continentale, Station Marine d'Endoume, Marseille, France.
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121
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Yahalomi D, Haddas-Sasson M, Rubinstein ND, Feldstein T, Diamant A, Huchon D. The Multipartite Mitochondrial Genome of Enteromyxum leei (Myxozoa): Eight Fast-Evolving Megacircles. Mol Biol Evol 2017; 34:1551-1556. [PMID: 28333349 DOI: 10.1093/molbev/msx072] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Myxozoans are a large group of poorly characterized cnidarian parasites. To gain further insight into their evolution, we sequenced the mitochondrial (mt) genome of Enteromyxum leei and reevaluate the mt genome structure of Kudoa iwatai. Although the typical animal mt genome is a compact, 13-25 kb, circular chromosome, the mt genome of E. leei was found to be fragmented into eight circular chromosomes of ∼23 kb, making it the largest described animal mt genome. Each chromosome was found to harbor a large noncoding region (∼15 kb), nearly identical between chromosomes. The protein coding genes show an unusually high rate of sequence evolution and possess little similarity to their cnidarian homologs. Only five protein coding genes could be identified and no tRNA genes. Surprisingly, the mt genome of K. iwatai was also found to be composed of two chromosomes. These observations confirm the remarkable plasticity of myxozoan mt genomes.
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Affiliation(s)
- Dayana Yahalomi
- Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Michal Haddas-Sasson
- Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Nimrod D Rubinstein
- Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Tamar Feldstein
- Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel.,The Steinhardt Museum of Natural History and Israel National Center for Biodiversity Studies, Tel Aviv University, Tel Aviv, Israel
| | - Arik Diamant
- National Center for Mariculture, Israel Oceanographic and Limnological Research, Eilat, Israel
| | - Dorothée Huchon
- Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel.,The Steinhardt Museum of Natural History and Israel National Center for Biodiversity Studies, Tel Aviv University, Tel Aviv, Israel
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122
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Brunet T, King N. The Origin of Animal Multicellularity and Cell Differentiation. Dev Cell 2017; 43:124-140. [PMID: 29065305 PMCID: PMC6089241 DOI: 10.1016/j.devcel.2017.09.016] [Citation(s) in RCA: 215] [Impact Index Per Article: 30.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 08/31/2017] [Accepted: 09/19/2017] [Indexed: 12/14/2022]
Abstract
Over 600 million years ago, animals evolved from a unicellular or colonial organism whose cell(s) captured bacteria with a collar complex, a flagellum surrounded by a microvillar collar. Using principles from evolutionary cell biology, we reason that the transition to multicellularity required modification of pre-existing mechanisms for extracellular matrix synthesis and cytokinesis. We discuss two hypotheses for the origin of animal cell types: division of labor from ancient plurifunctional cells and conversion of temporally alternating phenotypes into spatially juxtaposed cell types. Mechanistic studies in diverse animals and their relatives promise to deepen our understanding of animal origins and cell biology.
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Affiliation(s)
- Thibaut Brunet
- Howard Hughes Medical Institute and the Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Nicole King
- Howard Hughes Medical Institute and the Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA.
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123
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Whelan NV, Kocot KM, Moroz TP, Mukherjee K, Williams P, Paulay G, Moroz LL, Halanych KM. Ctenophore relationships and their placement as the sister group to all other animals. Nat Ecol Evol 2017; 1:1737-1746. [PMID: 28993654 PMCID: PMC5664179 DOI: 10.1038/s41559-017-0331-3] [Citation(s) in RCA: 145] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 08/31/2017] [Indexed: 11/17/2022]
Abstract
Ctenophora, compromising approximately 200 described species, is an important lineage for understanding metazoan evolution and is of great ecological and economic importance. Ctenophore diversity includes species with unique colloblasts used for prey capture, smooth and striated muscles, benthic and pelagic lifestyles, and locomotion with ciliated paddles or muscular propulsion. However, ancestral states of traits are debated and relationships among many lineages are unresolved. Here, using 27 newly sequenced ctenophore transcriptomes, publicly available data, and methods to control systematic error we establish the placement of Ctenophora as the sister group to all other animals and refine phylogenetic relationships within ctenophores. Molecular clock analyses suggest modern ctenophore diversity originated approximately 350MYA ± 88 MY, conflicting with previous hypotheses of approximately 65 MYA. We recover Euplokamis dunlapae, a species with striated muscles, as the sister lineage to other sampled ctenophores. Ancestral state reconstruction shows the most recent common ancestor of extant ctenophores was pelagic, possessed tentacles, was bioluminescent, and did not have separate sexes. Our results imply at least two transitions from a pelagic to a benthic lifestyle within Ctenophora, suggesting such transitions were more common in animal diversification than appreciated.
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Affiliation(s)
- Nathan V Whelan
- Molette Biology Laboratory for Environmental and Climate Change Studies, Department of Biological Sciences, Auburn University, Auburn, AL, 36849, USA. .,Warm Springs Fish Technology Center, US Fish and Wildlife Service, 5308 Spring St, Warm Springs, GA, 31830, USA.
| | - Kevin M Kocot
- Department of Biological Sciences, The University of Alabama, Box 870344, Tuscaloosa, AL, 35487, USA
| | - Tatiana P Moroz
- The Whitney Laboratory for Marine Biosciences, University of Florida, St. Augustine, FL, 32080, USA
| | - Krishanu Mukherjee
- The Whitney Laboratory for Marine Biosciences, University of Florida, St. Augustine, FL, 32080, USA
| | - Peter Williams
- The Whitney Laboratory for Marine Biosciences, University of Florida, St. Augustine, FL, 32080, USA
| | - Gustav Paulay
- Florida Museum of Natural History, University of Florida, Gainesville, FL, 32611, USA
| | - Leonid L Moroz
- The Whitney Laboratory for Marine Biosciences, University of Florida, St. Augustine, FL, 32080, USA. .,Department of Neuroscience and McKnight Brain Institute, University of Florida, Gainesville, FL, 32611, USA.
| | - Kenneth M Halanych
- Molette Biology Laboratory for Environmental and Climate Change Studies, Department of Biological Sciences, Auburn University, Auburn, AL, 36849, USA.
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124
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McTavish EJ, Drew BT, Redelings B, Cranston KA. How and Why to Build a Unified Tree of Life. Bioessays 2017; 39. [PMID: 28980328 DOI: 10.1002/bies.201700114] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 08/27/2017] [Indexed: 01/20/2023]
Abstract
Phylogenetic trees are a crucial backbone for a wide breadth of biological research spanning systematics, organismal biology, ecology, and medicine. In 2015, the Open Tree of Life project published a first draft of a comprehensive tree of life, summarizing digitally available taxonomic and phylogenetic knowledge. This paper reviews, investigates, and addresses the following questions as a follow-up to that paper, from the perspective of researchers involved in building this summary of the tree of life: Is there a tree of life and should we reconstruct it? Is available data sufficient to reconstruct the tree of life? Do we have access to phylogenetic inferences in usable form? Can we combine different phylogenetic estimates across the tree of life? And finally, what is the future of understanding the tree of life?
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Affiliation(s)
| | - Bryan T Drew
- University of Nebraska at Kearney, Kerney, NE, 68849, USA
| | - Ben Redelings
- University of Kansas, Lawrence, KS, 66045, USA Duke University, Durham NC 27705 USA; Ronin Institute, Durham, NC 27705 USA
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125
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Gupta A, Kaur H. A new pathogen, Myxobolus holzerae (Myxosporea: Myxozoa) causing severe gill disease in an Indian major carp Labeo rohita in a cold water wetland, Punjab (India). Microb Pathog 2017; 111:244-251. [DOI: 10.1016/j.micpath.2017.08.044] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 08/20/2017] [Accepted: 08/30/2017] [Indexed: 10/18/2022]
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126
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Functional and proteomic analysis of Ceratonova shasta (Cnidaria: Myxozoa) polar capsules reveals adaptations to parasitism. Sci Rep 2017; 7:9010. [PMID: 28827642 PMCID: PMC5566210 DOI: 10.1038/s41598-017-09955-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 07/20/2017] [Indexed: 12/16/2022] Open
Abstract
Myxozoa is a diverse, speciose group of microscopic parasites, recently placed within the phylum Cnidaria. Myxozoans are highly reduced in size and complexity relative to free-living cnidarians, yet they have retained specialized organelles known as polar capsules, akin to the nematocyst stinging capsules of free-living species. Whereas in free-living cnidarians the stinging capsules are used for prey capture or defense, in myxozoans they have the essential function of initiating the host infection process. To explore the evolutionary adaptation of polar capsules to parasitism, we used as a model organism Ceratonova shasta, which causes lethal disease in salmonids. Here, we report the first isolation of C. shasta myxospore polar capsules using a tailored dielectrophoresis-based microfluidic chip. Using electron microscopy and functional analysis we demonstrated that C. shasta tubules have no openings and are likely used to anchor the spore to the host. Proteomic analysis of C. shasta polar capsules suggested that they have retained typical structural and housekeeping proteins found in nematocysts of jellyfish, sea anemones and Hydra, but have lost the most important functional group in nematocysts, namely toxins. Our findings support the hypothesis that polar capsules and nematocysts are homologous organelles, which have adapted to their distinct functions.
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127
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Sarker S, Menanteau-Ledouble S, Kotob MH, El-Matbouli M. A RNAi-based therapeutic proof of concept targets salmonid whirling disease in vivo. PLoS One 2017; 12:e0178687. [PMID: 28575083 PMCID: PMC5456292 DOI: 10.1371/journal.pone.0178687] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 05/17/2017] [Indexed: 11/29/2022] Open
Abstract
Myxobolus cerebralis is a cnidarian-myxozoan parasite that causes salmonid whirling disease. M. cerebralis alternates between two hosts: (1) a vertebrate salmonid and (2) an invertebrate oligochaete, Tubifex tubifex. There is no successful treatment for salmonid whirling disease. MyxSP-1 is a M. cerebralis serine protease implicated in whirling disease pathogenesis. We hypothesized that short-interfering RNA (siRNA)-induced RNA interference (RNAi) can silence MyxSP-1 in the invertebrate host and abrogate the M. cerebralis life cycle. This would preclude whirling disease infection in the salmonid host. To test this hypothesis, we first developed a siRNA delivery protocol in T. tubifex. Second, we determined the effective dose for siRNA treatment of M. cerebralis-infected T. tubifex. M. cerebralis-infected T. tubifex were treated with different concentrations of MyxSP-1 or negative control siRNAs (1μM, 2μM, 5μM or 7μM) at 15°C for 24h, 48h, 72h and 96h, respectively. We monitored MyxSP-1 knockdown using real-time quantitative PCR (qPCR). siRNA treatment with MyxSP-1 siRNA at 2μM concentration for 24h at 15°C showed maximum significant MyxSP-1 knockdown in T. tubifex. Third, we determined the time points in the M. cerebralis life cycle in T. tubifex at which siRNA treatment was most effective. M. cerebralis-infected T. tubifex were treated with MyxSP-1 or negative control siRNAs (2μM concentration for 24h at 15°C) at 24 hours post-infection (24hpi), 48hpi, 72hpi, 96hpi, 1 month post-infection (1mpi), 2mpi and 3mpi, respectively. We observed that siRNA treatment of T. tubifex was most effective at 1mpi, 2mpi and 3mpi. Fourth, we immersed specific-pathogen-free rainbow trout fry in water inhabited by MyxSP-1 siRNA-treated T. tubifex (at 1mpi, 2mpi and 3mpi). The salmonids did not develop whirling disease and showed significant MyxSP-1 knockdown. We also observed long-term RNAi in T. tubifex. Together these results demonstrate a novel RNAi-based therapeutic proof of concept in vivo against salmonid whirling disease.
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Affiliation(s)
- Subhodeep Sarker
- Clinical Division of Fish Medicine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Vienna, Austria
- Discipline of Pharmacology, School of Medical Sciences, Sydney Medical School, The University of Sydney, Sydney, New South Wales, Australia
- * E-mail: (SS); (ME-M)
| | - Simon Menanteau-Ledouble
- Clinical Division of Fish Medicine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Mohamed H. Kotob
- Clinical Division of Fish Medicine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Vienna, Austria
- Department of Pathology, Faculty of Veterinary Medicine, Assiut University, Asyut, Egypt
| | - Mansour El-Matbouli
- Clinical Division of Fish Medicine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Vienna, Austria
- * E-mail: (SS); (ME-M)
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128
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Boomsma JJ, Gawne R. Superorganismality and caste differentiation as points of no return: how the major evolutionary transitions were lost in translation. Biol Rev Camb Philos Soc 2017; 93:28-54. [PMID: 28508537 DOI: 10.1111/brv.12330] [Citation(s) in RCA: 122] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Revised: 03/04/2017] [Accepted: 03/08/2017] [Indexed: 12/27/2022]
Abstract
More than a century ago, William Morton Wheeler proposed that social insect colonies can be regarded as superorganisms when they have morphologically differentiated reproductive and nursing castes that are analogous to the metazoan germ-line and soma. Following the rise of sociobiology in the 1970s, Wheeler's insights were largely neglected, and we were left with multiple new superorganism concepts that are mutually inconsistent and uninformative on how superorganismality originated. These difficulties can be traced to the broadened sociobiological concept of eusociality, which denies that physical queen-worker caste differentiation is a universal hallmark of superorganismal colonies. Unlike early evolutionary naturalists and geneticists such as Weismann, Huxley, Fisher and Haldane, who set out to explain the acquisition of an unmated worker caste, the goal of sociobiology was to understand the evolution of eusociality, a broad-brush convenience category that covers most forms of cooperative breeding. By lumping a diverse spectrum of social systems into a single category, and drawing attention away from the evolution of distinct quantifiable traits, the sociobiological tradition has impeded straightforward connections between inclusive fitness theory and the major evolutionary transitions paradigm for understanding irreversible shifts to higher organizational complexity. We evaluate the history by which these inconsistencies accumulated, develop a common-cause approach for understanding the origins of all major transitions in eukaryote hierarchical complexity, and use Hamilton's rule to argue that they are directly comparable. We show that only Wheeler's original definition of superorganismality can be unambiguously linked to irreversible evolutionary transitions from context-dependent reproductive altruism to unconditional differentiation of permanently unmated castes in the ants, corbiculate bees, vespine wasps and higher termites. We argue that strictly monogamous parents were a necessary, albeit not sufficient condition for all transitions to superorganismality, analogous to single-zygote bottlenecking being a necessary but not sufficient condition for the convergent origins of complex soma across multicellular eukaryotes. We infer that conflict reduction was not a necessary condition for the origin of any of these major transitions, and conclude that controversies over the status of inclusive fitness theory primarily emanate from the arbitrarily defined sociobiological concepts of superorganismality and eusociality, not from the theory itself.
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Affiliation(s)
- Jacobus J Boomsma
- Centre for Social Evolution, Department of Biology, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen, Denmark.,Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK
| | - Richard Gawne
- Centre for Social Evolution, Department of Biology, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen, Denmark.,Department of Biology, Duke University, 130 Science Drive, Durham, NC, 27708, USA
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129
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Zatti SA, Atkinson SD, Bartholomew JL, Maia AAM, Adriano EA. Amazonian waters harbour an ancient freshwater Ceratomyxa lineage (Cnidaria: Myxosporea). Acta Trop 2017; 169:100-106. [PMID: 28185825 DOI: 10.1016/j.actatropica.2017.02.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 01/17/2017] [Accepted: 02/06/2017] [Indexed: 01/18/2023]
Abstract
A new species of Ceratomyxa parasitizing the gall bladder of Cichla monoculus, an endemic cichlid fish from the Amazon basin in Brazil, is described using morphological and molecular data. In the bile, both immature and mature myxospores were found floating freely or inside elongated plasmodia: length 304 (196-402) μm and width 35.7 (18.3-55.1) μm. Mature spores were elongated and only slightly crescent-shaped in frontal view with a prominent sutural line between two valve cells, which had rounded ends. Measurements of formalin-fixed myxospores: length 6.3±0.6 (5.1-7.5) μm, thickness 41.2±2.9 (37.1-47.6) μm, posterior angle 147°. Lateral projections slightly asymmetric, with lengths 19.3±1.4μm and 20.5±1.3μm. Two ovoid, equal size polar capsules, length 2.6±0.3 (2-3.3) μm, width 2.5±0.4 (1.8-3.7) μm, located adjacent to the suture and containing polar filaments with 3-4 turns. The small subunit ribosomal DNA sequence of 1605 nt was no more than 97% similar to any other sequence in GenBank, and together with the host, locality and morphometric data, supports diagnosis of the parasite as a new species, Ceratomyxa brasiliensis n. sp. Maximum parsimony and maximum likelihood analyses showed that C. brasiliensis n. sp. clustered within the marine Ceratomyxa clade, but was in a basally divergent lineage with two other freshwater species from the Amazon basin. Our results are consistent with previous studies that show Ceratomyxa species can cluster according to both geography and host ecotype, and that the few known freshwater species diverged from marine cousins relatively early in evolution of the genus, possibly driven by marine incursions into riverine environments.
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Affiliation(s)
- Suellen A Zatti
- Department of Animal Biology, Institute of Biology, University of Campinas, Rua Monteiro Lobato, 255, CEP 13083-862, Campinas, SP, Brazil
| | - Stephen D Atkinson
- Department of Microbiology, Oregon State University, 97331, Corvallis, OR, USA
| | - Jerri L Bartholomew
- Department of Microbiology, Oregon State University, 97331, Corvallis, OR, USA
| | - Antônio A M Maia
- Department of Veterinary Medicine, Faculty of Animal Science and Food Engineering, São Paulo University, Avenida Duque de Caxias Norte, 225, CEP 13635-900, Pirassununga, SP, Brazil
| | - Edson A Adriano
- Department of Animal Biology, Institute of Biology, University of Campinas, Rua Monteiro Lobato, 255, CEP 13083-862, Campinas, SP, Brazil; Department of Ecology and Evolutionary Biology, Federal University of São Paulo, Rua Professor Arthur Riedel, 275, Jardim Eldorado, CEP 09972-270, Diadema, SP, Brazil.
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130
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Gerdol M, Venier P, Edomi P, Pallavicini A. Diversity and evolution of TIR-domain-containing proteins in bivalves and Metazoa: New insights from comparative genomics. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2017; 70:145-164. [PMID: 28109746 DOI: 10.1016/j.dci.2017.01.014] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 01/13/2017] [Accepted: 01/17/2017] [Indexed: 06/06/2023]
Abstract
The Toll/interleukin-1 receptor (TIR) domain has a fundamental role in the innate defence response of plants, vertebrate and invertebrate animals. Mostly found in the cytosolic side of membrane-bound receptor proteins, it mediates the intracellular signalling upon pathogen recognition via heterotypic interactions. Although a number of TIR-domain-containing (TIR-DC) proteins have been characterized in vertebrates, their evolutionary relationships and functional role in protostomes are still largely unknown. Due to the high abundance and diversity of TIR-DC proteins in bivalve molluscs, we investigated this class of marine invertebrates as a case study. The analysis of the available genomic and transcriptomic data allowed the identification of over 400 full-length sequences and their classification in protein families based on sequence homology and domain organization. In addition to TLRs and MyD88 adaptors, bivalves possess a surprisingly large repertoire of intracellular TIR-DC proteins, which are conserved across a broad range of metazoan taxa. Overall, we report the expansion and diversification of TIR-DC proteins in several invertebrate lineages and the identification of many novel protein families possibly involved in both immune-related signalling and embryonic development.
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Affiliation(s)
- Marco Gerdol
- University of Trieste, Department of Life Sciences, Via Licio Giorgieri 5, 34127 Trieste, Italy.
| | - Paola Venier
- University of Padova, Department of Biology, Via Ugo Bassi 58/B, 35131 Padova, Italy.
| | - Paolo Edomi
- University of Trieste, Department of Life Sciences, Via Licio Giorgieri 5, 34127 Trieste, Italy.
| | - Alberto Pallavicini
- University of Trieste, Department of Life Sciences, Via Licio Giorgieri 5, 34127 Trieste, Italy.
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131
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A Large and Consistent Phylogenomic Dataset Supports Sponges as the Sister Group to All Other Animals. Curr Biol 2017; 27:958-967. [PMID: 28318975 DOI: 10.1016/j.cub.2017.02.031] [Citation(s) in RCA: 283] [Impact Index Per Article: 40.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 02/07/2017] [Accepted: 02/13/2017] [Indexed: 01/11/2023]
Abstract
Resolving the early diversification of animal lineages has proven difficult, even using genome-scale datasets. Several phylogenomic studies have supported the classical scenario in which sponges (Porifera) are the sister group to all other animals ("Porifera-sister" hypothesis), consistent with a single origin of the gut, nerve cells, and muscle cells in the stem lineage of eumetazoans (bilaterians + ctenophores + cnidarians). In contrast, several other studies have recovered an alternative topology in which ctenophores are the sister group to all other animals (including sponges). The "Ctenophora-sister" hypothesis implies that eumetazoan-specific traits, such as neurons and muscle cells, either evolved once along the metazoan stem lineage and were then lost in sponges and placozoans or evolved at least twice independently in Ctenophora and in Cnidaria + Bilateria. Here, we report on our reconstruction of deep metazoan relationships using a 1,719-gene dataset with dense taxonomic sampling of non-bilaterian animals that was assembled using a semi-automated procedure, designed to reduce known error sources. Our dataset outperforms previous metazoan gene superalignments in terms of data quality and quantity. Analyses with a best-fitting site-heterogeneous evolutionary model provide strong statistical support for placing sponges as the sister-group to all other metazoans, with ctenophores emerging as the second-earliest branching animal lineage. Only those methodological settings that exacerbated long-branch attraction artifacts yielded Ctenophora-sister. These results show that methodological issues must be carefully addressed to tackle difficult phylogenetic questions and pave the road to a better understanding of how fundamental features of animal body plans have emerged.
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132
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Leclère L, Röttinger E. Diversity of Cnidarian Muscles: Function, Anatomy, Development and Regeneration. Front Cell Dev Biol 2017; 4:157. [PMID: 28168188 PMCID: PMC5253434 DOI: 10.3389/fcell.2016.00157] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 12/30/2016] [Indexed: 12/12/2022] Open
Abstract
The ability to perform muscle contractions is one of the most important and distinctive features of eumetazoans. As the sister group to bilaterians, cnidarians (sea anemones, corals, jellyfish, and hydroids) hold an informative phylogenetic position for understanding muscle evolution. Here, we review current knowledge on muscle function, diversity, development, regeneration and evolution in cnidarians. Cnidarian muscles are involved in various activities, such as feeding, escape, locomotion and defense, in close association with the nervous system. This variety is reflected in the large diversity of muscle organizations found in Cnidaria. Smooth epithelial muscle is thought to be the most common type, and is inferred to be the ancestral muscle type for Cnidaria, while striated muscle fibers and non-epithelial myocytes would have been convergently acquired within Cnidaria. Current knowledge of cnidarian muscle development and its regeneration is limited. While orthologs of myogenic regulatory factors such as MyoD have yet to be found in cnidarian genomes, striated muscle formation potentially involves well-conserved myogenic genes, such as twist and mef2. Although satellite cells have yet to be identified in cnidarians, muscle plasticity (e.g., de- and re-differentiation, fiber repolarization) in a regenerative context and its potential role during regeneration has started to be addressed in a few cnidarian systems. The development of novel tools to study those organisms has created new opportunities to investigate in depth the development and regeneration of cnidarian muscle cells and how they contribute to the regenerative process.
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Affiliation(s)
- Lucas Leclère
- Sorbonne Universités, UPMC Univ Paris 06, CNRS, Laboratoire de Biologie du Développement de Villefranche-sur-mer (LBDV) Villefranche-sur-mer, France
| | - Eric Röttinger
- Université Côte d'Azur, CNRS, INSERM, Institute for Research on Cancer and Aging (IRCAN) Nice, France
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133
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Xi BW, Li P, Liu QC, Chen K, Teng T, Xie J. Description of a new Neoactinomyxum type actinosporean from the oligochaete Branchiura sowerbyi Beddard. Syst Parasitol 2017; 94:73-80. [PMID: 28062987 DOI: 10.1007/s11230-016-9677-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Accepted: 09/23/2016] [Indexed: 10/20/2022]
Abstract
Actinosporean infection of oligochaetes living in the mud of a commercial gibel carp pond with myxosporean disease was studied. Six actinospore types were detected exclusively from the oligochaete Branchiura sowerbyi Beddard with very high prevalence (18%). Five out of the six types were identified as the same actinosporeans described in previous reports, the sixth actinosporean was identified as a new Neoactinomyxum type and described here based on morphological and molecular characterisation. Spore body of the actinospore was globular, much smaller than caudal processes. Three caudal processes were disc-like in apical view, hemispherical in side view, closer together and encircling the spore body. The number of sporoplasm cells was detected as eight in one specimen. The new actinosporean markedly differed from other Neoactinomyxum types in literature having much bigger caudal processes. DNA sequence analyses further confirmed the morphological identification, and revealed the actinosporean described here (KU641392) possessed less than 94% sequence similarity with myxozoans available in the GenBank database.
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Affiliation(s)
- Bing Wen Xi
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China.
| | - Peng Li
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China.,Wuxi Fishery College, Nanjing Agricultural University, Wuxi, 210095, China
| | | | - Kai Chen
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China
| | - Tao Teng
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China.,Wuxi Fishery College, Nanjing Agricultural University, Wuxi, 210095, China
| | - Jun Xie
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, China.
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134
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Ben-David J, Atkinson SD, Pollak Y, Yossifon G, Shavit U, Bartholomew JL, Lotan T. Myxozoan polar tubules display structural and functional variation. Parasit Vectors 2016; 9:549. [PMID: 27741948 PMCID: PMC5064783 DOI: 10.1186/s13071-016-1819-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 09/28/2016] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Myxozoa is a speciose group of endoparasitic cnidarians that can cause severe ecological and economic effects. Although highly reduced compared to free-living cnidarians, myxozoans have retained the phylum-defining stinging organelles, known as cnidae or polar capsules, which are essential to initiating host infection. To explore the adaptations of myxozoan polar capsules, we compared the structure, firing process and content release mechanism of polar tubules in myxospores of three Myxobolus species including M. cerebralis, the causative agent of whirling disease. RESULTS We found novel functions and morphologies in myxozoan polar tubules. High-speed video analysis of the firing process of capsules from the three Myxobolus species showed that all polar tubules rapidly extended and then contracted, an elasticity phenomenon that is unknown in free-living cnidarians. Interestingly, the duration of the tubule release differed among the three species by more than two orders of magnitude, ranging from 0.35 to 10 s. By dye-labeling the polar capsules prior to firing, we discovered that two of the species could release their entire capsule content, a delivery process not previously known from myxozoans. Having the role of content delivery and not simply anchoring suggests that cytotoxic or proteolytic compounds may be present in the capsule. Moreover, while free-living cnidarians inject most of the toxic content through the distal tip of the tubule, our video and ultrastructure analyses of the myxozoan tubules revealed patterns of double spirals of nodules and pores along parts of the tubules, and showed that the distal tip of the tubules was sealed. This helical pattern and distribution of openings may minimize the tubule mechanical weakness and improve resistance to the stress impose by firing. The finding that myxozoan tubule characteristics are very different from those of free-living cnidarians is suggestive of their adaptation to parasitic life. CONCLUSIONS These findings show that myxozoan polar tubules have more functions than previously assumed, and provide insight into their evolution from free-living ancestors.
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Affiliation(s)
- Jonathan Ben-David
- Department of Marine Biology, Leon H. Charney School of Marine Sciences, University of Haifa, Haifa, 31905, Israel
| | - Stephen D Atkinson
- Department of Microbiology, Oregon State University, Nash Hall 226, Corvallis, OR, 97331, USA
| | - Yulia Pollak
- Electron Microscopy Unit, Faculty of Natural Sciences, University of Haifa, Haifa, 31905, Israel
| | - Gilad Yossifon
- Faculty of Mechanical Engineering, Technion, Haifa, 32000, Israel
| | - Uri Shavit
- Faculty of Civil and Environmental Engineering, Technion, Haifa, 32000, Israel
| | - Jerri L Bartholomew
- Department of Microbiology, Oregon State University, Nash Hall 226, Corvallis, OR, 97331, USA
| | - Tamar Lotan
- Department of Marine Biology, Leon H. Charney School of Marine Sciences, University of Haifa, Haifa, 31905, Israel.
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135
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Affiliation(s)
- Gonzalo Giribet
- Museum of Comparative Zoology & Department of Organismic and Evolutionary Biology Harvard University 26 Oxford Street Cambridge MA 02138 USA
- Department of Life Sciences The Natural History Museum Cromwell Road London SW7 5BD UK
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136
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Genomic Mining of Phylogenetically Informative Nuclear Markers in Bark and Ambrosia Beetles. PLoS One 2016; 11:e0163529. [PMID: 27668729 PMCID: PMC5036811 DOI: 10.1371/journal.pone.0163529] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 09/10/2016] [Indexed: 11/19/2022] Open
Abstract
Deep level insect relationships are generally difficult to resolve, especially within taxa of the most diverse and species rich holometabolous orders. In beetles, the major diversity occurs in the Phytophaga, including charismatic groups such as leaf beetles, longhorn beetles and weevils. Bark and ambrosia beetles are wood boring weevils that contribute 12 percent of the diversity encountered in Curculionidae, one of the largest families of beetles with more than 50000 described species. Phylogenetic resolution in groups of Cretaceous age has proven particularly difficult and requires large quantity of data. In this study, we investigated 100 nuclear genes in order to select a number of markers with low evolutionary rates and high phylogenetic signal. A PCR screening using degenerate primers was applied to 26 different weevil species. We obtained sequences from 57 of the 100 targeted genes. Sequences from each nuclear marker were aligned and examined for detecting multiple copies, pseudogenes and introns. Phylogenetic informativeness (PI) and the capacity for reconstruction of previously established phylogenetic relationships were used as proxies for selecting a subset of the 57 amplified genes. Finally, we selected 16 markers suitable for large-scale phylogenetics of Scolytinae and related weevil taxa.
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137
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Pratlong M, Rancurel C, Pontarotti P, Aurelle D. Monophyly of Anthozoa (Cnidaria): why do nuclear and mitochondrial phylogenies disagree? ZOOL SCR 2016. [DOI: 10.1111/zsc.12208] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Marine Pratlong
- Aix Marseille Univ; Univ Avignon; CNRS; IRD; IMBE; Marseille France
- Aix Marseille Univ; CNRS; Centrale Marseille, I2M, Equipe Evolution Biologique et Modélisation; Marseille France
| | - Corinne Rancurel
- INRA; University Nice Sophia Antipolis; CNRS; UMR 1355-7254 Institut Sophia Agrobiotech; Sophia Antipolis France
| | - Pierre Pontarotti
- Aix Marseille Univ; CNRS; Centrale Marseille, I2M, Equipe Evolution Biologique et Modélisation; Marseille France
| | - Didier Aurelle
- Aix Marseille Univ; Univ Avignon; CNRS; IRD; IMBE; Marseille France
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138
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Siebert S, Juliano CE. Sex, polyps, and medusae: Determination and maintenance of sex in cnidarians. Mol Reprod Dev 2016; 84:105-119. [DOI: 10.1002/mrd.22690] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 08/10/2016] [Indexed: 01/22/2023]
Affiliation(s)
- Stefan Siebert
- Department of Molecular and Cellular Biology; University of California; Davis California
| | - Celina E. Juliano
- Department of Molecular and Cellular Biology; University of California; Davis California
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139
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Fernández R, Edgecombe GD, Giribet G. Exploring Phylogenetic Relationships within Myriapoda and the Effects of Matrix Composition and Occupancy on Phylogenomic Reconstruction. Syst Biol 2016; 65:871-89. [PMID: 27162151 PMCID: PMC4997009 DOI: 10.1093/sysbio/syw041] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Accepted: 04/28/2016] [Indexed: 11/14/2022] Open
Abstract
Myriapods, including the diverse and familiar centipedes and millipedes, are one of the dominant terrestrial arthropod groups. Although molecular evidence has shown that Myriapoda is monophyletic, its internal phylogeny remains contentious and understudied, especially when compared to those of Chelicerata and Hexapoda. Until now, efforts have focused on taxon sampling (e.g., by including a handful of genes from many species) or on maximizing matrix size (e.g., by including hundreds or thousands of genes in just a few species), but a phylogeny maximizing sampling at both levels remains elusive. In this study, we analyzed 40 Illumina transcriptomes representing 3 of the 4 myriapod classes (Diplopoda, Chilopoda, and Symphyla); 25 transcriptomes were newly sequenced to maximize representation at the ordinal level in Diplopoda and at the family level in Chilopoda. Ten supermatrices were constructed to explore the effect of several potential phylogenetic biases (e.g., rate of evolution, heterotachy) at 3 levels of gene occupancy per taxon (50%, 75%, and 90%). Analyses based on maximum likelihood and Bayesian mixture models retrieved monophyly of each myriapod class, and resulted in 2 alternative phylogenetic positions for Symphyla, as sister group to Diplopoda + Chilopoda, or closer to Diplopoda, the latter hypothesis having been traditionally supported by morphology. Within centipedes, all orders were well supported, but 2 deep nodes remained in conflict in the different analyses despite dense taxon sampling at the family level. Relationships among centipede orders in all analyses conducted with the most complete matrix (90% occupancy) are at odds not only with the sparser but more gene-rich supermatrices (75% and 50% supermatrices) and with the matrices optimizing phylogenetic informativeness or most conserved genes, but also with previous hypotheses based on morphology, development, or other molecular data sets. Our results indicate that a high percentage of ribosomal proteins in the most complete matrices, in conjunction with distance from the root, can act in concert to compromise the estimated relationships within the ingroup. We discuss the implications of these findings in the context of the ever more prevalent quest for completeness in phylogenomic studies.
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Affiliation(s)
- Rosa Fernández
- Museum of Comparative Zoology & Department of Organismic and Evolutionary Biology, Harvard University, 26 Oxford Street, Cambridge, MA 02138, USA
| | - Gregory D Edgecombe
- Department of Earth Sciences, The Natural History Museum, Cromwell Road, London SW7 5BD, UK
| | - Gonzalo Giribet
- Museum of Comparative Zoology & Department of Organismic and Evolutionary Biology, Harvard University, 26 Oxford Street, Cambridge, MA 02138, USA
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140
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Abstract
An analysis of Hox genes reveals that the body of the adorably weird tardigrades is essentially a truncated front end. This illustrates that loss and simplification are a hallmark of the evolution of animal body plans.
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141
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Martindale MQ. The onset of regenerative properties in ctenophores. Curr Opin Genet Dev 2016; 40:113-119. [PMID: 27420173 DOI: 10.1016/j.gde.2016.06.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 06/18/2016] [Accepted: 06/24/2016] [Indexed: 12/18/2022]
Abstract
Ctenophores are a clade of animals that branch off at the base of the animal tree. They have a unique and delicate body plan, and distinct pattern forming mechanisms at different life history stages. They have a stereotyped embryonic cell lineage and are highly 'mosaic' as embryos, but most have amazing capacity to regenerate as adults. Unfortunately, only a handful of ctenophore species have been studied in detail. This review summarizes the key features of the regenerative properties of adults, and the characteristics of the embryological onset of regenerative abilities. The genomes of several ctenophore species have already been sequenced, and these resources set the stage for more detailed cellular and molecular analysis of body plan patterning in this group.
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Affiliation(s)
- Mark Q Martindale
- Whitney Lab for Marine Bioscience, University of Florida, 9505 Oceanshore Blvd, St. Augustine, FL 32080, United States.
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142
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Mikhailov K, Slyusarev G, Nikitin M, Logacheva M, Penin A, Aleoshin V, Panchin Y. The Genome of Intoshia linei Affirms Orthonectids as Highly Simplified Spiralians. Curr Biol 2016; 26:1768-1774. [DOI: 10.1016/j.cub.2016.05.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 05/02/2016] [Accepted: 05/03/2016] [Indexed: 11/27/2022]
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143
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O'Malley MA, Wideman JG, Ruiz-Trillo I. Losing Complexity: The Role of Simplification in Macroevolution. Trends Ecol Evol 2016; 31:608-621. [PMID: 27212432 DOI: 10.1016/j.tree.2016.04.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 04/18/2016] [Accepted: 04/19/2016] [Indexed: 10/21/2022]
Abstract
Macroevolutionary patterns can be produced by combinations of diverse and even oppositional dynamics. A growing body of data indicates that secondary simplifications of molecular and cellular structures are common. Some major diversifications in eukaryotes have occurred because of loss and minimalisation; numerous episodes in prokaryote evolution have likewise been driven by the reduction of structure. After examining a range of examples of secondary simplification and its consequences across the tree of life, we address how macroevolutionary explanations might incorporate simplification as well as complexification, and adaptive as well as nonadaptive dynamics.
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Affiliation(s)
- Maureen A O'Malley
- UMR5164, University of Bordeaux, 146 Rue Léo Saignat, Bordeaux 33076, France.
| | | | - Iñaki Ruiz-Trillo
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37-49, 08003 Barcelona, Spain; Departament de Genètica, Universitat de Barcelona, 08028 Barcelona, Spain; Institució Catalana de Recerca i Estudis Avançats, Pg Lluis Companys 23, 08010 Barcelona, Spain
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144
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Mendoza-Becerril MA, Maronna MM, Pacheco MLAF, Simões MG, Leme JM, Miranda LS, Morandini AC, Marques AC. An evolutionary comparative analysis of the medusozoan (Cnidaria) exoskeleton. Zool J Linn Soc 2016. [DOI: 10.1111/zoj.12415] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- María A. Mendoza-Becerril
- Department of Zoology; Institute of Biosciences; University of São Paulo; Rua do Matão, Trav. 14, 101 05508-090 São Paulo Brazil
| | - Maximiliano M. Maronna
- Department of Zoology; Institute of Biosciences; University of São Paulo; Rua do Matão, Trav. 14, 101 05508-090 São Paulo Brazil
| | - Mírian L. A. F. Pacheco
- Department of Biology; Federal University of Sao Carlos; Rodovia João Leme dos Santos - até km 104.000 Parque Reserva Fazenda Imperial 18052780 Sorocaba São Paulo Brazil
| | - Marcello G. Simões
- Department of Zoology; Laboratory of Paleozoology; São Paulo State University Botucatu; Jardim Santo Inácio (Rubião Junior) 18618970 Botucatu São Paulo Brazil
| | - Juliana M. Leme
- Department of Sedimentary and Environmental Geology; Institute of Geosciences; University of São Paulo; Rua do Lago, 562 05508-080 São Paulo Brazil
| | - Lucília S. Miranda
- Department of Zoology; Institute of Biosciences; University of São Paulo; Rua do Matão, Trav. 14, 101 05508-090 São Paulo Brazil
| | - André C. Morandini
- Department of Zoology; Institute of Biosciences; University of São Paulo; Rua do Matão, Trav. 14, 101 05508-090 São Paulo Brazil
| | - Antonio C. Marques
- Department of Zoology; Institute of Biosciences; University of São Paulo; Rua do Matão, Trav. 14, 101 05508-090 São Paulo Brazil
- Center for Marine Biology; University of São Paulo; Rodovia Manoel H. Do Rego km 131.5 CEP 11600-000 São Sebastião São Paulo Brazil
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145
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Sasson DA, Ryan JF. The sex lives of ctenophores: the influence of light, body size, and self-fertilization on the reproductive output of the sea walnut, Mnemiopsis leidyi. PeerJ 2016; 4:e1846. [PMID: 27042395 PMCID: PMC4811168 DOI: 10.7717/peerj.1846] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 03/03/2016] [Indexed: 12/31/2022] Open
Abstract
Ctenophores (comb jellies) are emerging as important animals for investigating fundamental questions across numerous branches of biology (e.g., evodevo, neuroscience and biogeography). A few ctenophore species including, most notably, Mnemiopsis leidyi, are considered as invasive species, adding to the significance of studying ctenophore ecology. Despite the growing interest in ctenophore biology, relatively little is known about their reproduction. Like most ctenophores, M. leidyi is a simultaneous hermaphrodite capable of self-fertilization. In this study, we assess the influence of light on spawning, the effect of body size on spawning likelihood and reproductive output, and the cost of self-fertilization on egg viability in M. leidyi. Our results suggest that M. leidyi spawning is more strongly influenced by circadian rhythms than specific light cues and that body size significantly impacts spawning and reproductive output. Mnemiopsis leidyi adults that spawned alone produced a lower percentage of viable embryos versus those that spawned in pairs, suggesting that self-fertilization may be costly in this species. These results provide insight into the reproductive ecology of M. leidyi and provide a fundamental resource for researchers working with them in the laboratory.
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Affiliation(s)
- Daniel A Sasson
- Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, Florida, United States of America; Department of Biology, University of Florida, Gainesville, Florida, United States of America
| | - Joseph F Ryan
- Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, Florida, United States of America; Department of Biology, University of Florida, Gainesville, Florida, United States of America
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146
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147
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Okamura B, Gruhl A. Myxozoa + Polypodium: A Common Route to Endoparasitism. Trends Parasitol 2016; 32:268-271. [PMID: 26830727 DOI: 10.1016/j.pt.2016.01.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 01/13/2016] [Indexed: 11/16/2022]
Abstract
Recent evidence places the problematic Polypodium, a parasite of fish eggs, firmly as sister taxon to Myxozoa within the Cnidaria. This resolution suggests a single route to endoparasitism in Cnidaria, with larval stages of a common ancestor exploiting fish as first hosts. It also enables new interpretations and insights regarding evolutionary transitions associated with endoparasitism.
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Affiliation(s)
- Beth Okamura
- Natural History Museum, Department of Life Sciences, London, UK.
| | - Alexander Gruhl
- Natural History Museum, Department of Life Sciences, London, UK; Max Planck Institute for Marine Microbiology, Bremen, Germany
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148
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149
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Pisani D, Pett W, Dohrmann M, Feuda R, Rota-Stabelli O, Philippe H, Lartillot N, Wörheide G. Genomic data do not support comb jellies as the sister group to all other animals. Proc Natl Acad Sci U S A 2015; 112:15402-7. [PMID: 26621703 PMCID: PMC4687580 DOI: 10.1073/pnas.1518127112] [Citation(s) in RCA: 200] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Understanding how complex traits, such as epithelia, nervous systems, muscles, or guts, originated depends on a well-supported hypothesis about the phylogenetic relationships among major animal lineages. Traditionally, sponges (Porifera) have been interpreted as the sister group to the remaining animals, a hypothesis consistent with the conventional view that the last common animal ancestor was relatively simple and more complex body plans arose later in evolution. However, this premise has recently been challenged by analyses of the genomes of comb jellies (Ctenophora), which, instead, found ctenophores as the sister group to the remaining animals (the "Ctenophora-sister" hypothesis). Because ctenophores are morphologically complex predators with true epithelia, nervous systems, muscles, and guts, this scenario implies these traits were either present in the last common ancestor of all animals and were lost secondarily in sponges and placozoans (Trichoplax) or, alternatively, evolved convergently in comb jellies. Here, we analyze representative datasets from recent studies supporting Ctenophora-sister, including genome-scale alignments of concatenated protein sequences, as well as a genomic gene content dataset. We found no support for Ctenophora-sister and conclude it is an artifact resulting from inadequate methodology, especially the use of simplistic evolutionary models and inappropriate choice of species to root the metazoan tree. Our results reinforce a traditional scenario for the evolution of complexity in animals, and indicate that inferences about the evolution of Metazoa based on the Ctenophora-sister hypothesis are not supported by the currently available data.
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Affiliation(s)
- Davide Pisani
- School of Earth Sciences, University of Bristol, Bristol BS8 1TG, United Kingdom; School of Biological Sciences, University of Bristol, Bristol BS8 1TG, United Kingdom;
| | - Walker Pett
- Laboratoire de Biométrie et Biologie Évolutive, Université Lyon 1, CNRS, UMR 5558, 69622 Villeurbanne cedex, France
| | - Martin Dohrmann
- Department of Earth & Environmental Sciences & GeoBio-Center, Ludwig-Maximilians-Universität München, Munich 80333, Germany
| | - Roberto Feuda
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125
| | - Omar Rota-Stabelli
- Department of Sustainable Agro-Ecosystems and Bioresources, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all' Adige 38010, Italy
| | - Hervé Philippe
- Centre for Biodiversity Theory and Modelling, USR CNRS 2936, Station d'Ecologie Expérimentale du CNRS, Moulis 09200, France; Département de Biochimie, Centre Robert-Cedergren, Université de Montréal, Montreal, QC, Canada H3C 3J7
| | - Nicolas Lartillot
- Laboratoire de Biométrie et Biologie Évolutive, Université Lyon 1, CNRS, UMR 5558, 69622 Villeurbanne cedex, France
| | - Gert Wörheide
- Department of Earth & Environmental Sciences & GeoBio-Center, Ludwig-Maximilians-Universität München, Munich 80333, Germany; Bayerische Staatssammlung für Paläontologie und Geologie, Munich 80333, Germany
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