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Monk T, Dennler N, Ralph N, Rastogi S, Afshar S, Urbizagastegui P, Jarvis R, van Schaik A, Adamatzky A. Electrical Signaling Beyond Neurons. Neural Comput 2024; 36:1939-2029. [PMID: 39141803 DOI: 10.1162/neco_a_01696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 05/21/2024] [Indexed: 08/16/2024]
Abstract
Neural action potentials (APs) are difficult to interpret as signal encoders and/or computational primitives. Their relationships with stimuli and behaviors are obscured by the staggering complexity of nervous systems themselves. We can reduce this complexity by observing that "simpler" neuron-less organisms also transduce stimuli into transient electrical pulses that affect their behaviors. Without a complicated nervous system, APs are often easier to understand as signal/response mechanisms. We review examples of nonneural stimulus transductions in domains of life largely neglected by theoretical neuroscience: bacteria, protozoans, plants, fungi, and neuron-less animals. We report properties of those electrical signals-for example, amplitudes, durations, ionic bases, refractory periods, and particularly their ecological purposes. We compare those properties with those of neurons to infer the tasks and selection pressures that neurons satisfy. Throughout the tree of life, nonneural stimulus transductions time behavioral responses to environmental changes. Nonneural organisms represent the presence or absence of a stimulus with the presence or absence of an electrical signal. Their transductions usually exhibit high sensitivity and specificity to a stimulus, but are often slow compared to neurons. Neurons appear to be sacrificing the specificity of their stimulus transductions for sensitivity and speed. We interpret cellular stimulus transductions as a cell's assertion that it detected something important at that moment in time. In particular, we consider neural APs as fast but noisy detection assertions. We infer that a principal goal of nervous systems is to detect extremely weak signals from noisy sensory spikes under enormous time pressure. We discuss neural computation proposals that address this goal by casting neurons as devices that implement online, analog, probabilistic computations with their membrane potentials. Those proposals imply a measurable relationship between afferent neural spiking statistics and efferent neural membrane electrophysiology.
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Affiliation(s)
- Travis Monk
- International Centre for Neuromorphic Systems, MARCS Institute, Western Sydney University, Sydney, NSW 2747, Australia
| | - Nik Dennler
- International Centre for Neuromorphic Systems, MARCS Institute, Western Sydney University, Sydney, NSW 2747, Australia
- Biocomputation Group, University of Hertfordshire, Hatfield, Hertfordshire AL10 9AB, U.K.
| | - Nicholas Ralph
- International Centre for Neuromorphic Systems, MARCS Institute, Western Sydney University, Sydney, NSW 2747, Australia
| | - Shavika Rastogi
- International Centre for Neuromorphic Systems, MARCS Institute, Western Sydney University, Sydney, NSW 2747, Australia
- Biocomputation Group, University of Hertfordshire, Hatfield, Hertfordshire AL10 9AB, U.K.
| | - Saeed Afshar
- International Centre for Neuromorphic Systems, MARCS Institute, Western Sydney University, Sydney, NSW 2747, Australia
| | - Pablo Urbizagastegui
- International Centre for Neuromorphic Systems, MARCS Institute, Western Sydney University, Sydney, NSW 2747, Australia
| | - Russell Jarvis
- International Centre for Neuromorphic Systems, MARCS Institute, Western Sydney University, Sydney, NSW 2747, Australia
| | - André van Schaik
- International Centre for Neuromorphic Systems, MARCS Institute, Western Sydney University, Sydney, NSW 2747, Australia
| | - Andrew Adamatzky
- Unconventional Computing Laboratory, University of the West of England, Bristol BS16 1QY, U.K.
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2
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Dallagnol LC, Cônsoli FL. Evolutionary and phylogenetic insights from the mitochondrial genomic analysis of Diceraeus melacanthus and D. furcatus (Hemiptera: Pentatomidae). Sci Rep 2024; 14:12861. [PMID: 38834792 DOI: 10.1038/s41598-024-63584-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Accepted: 05/30/2024] [Indexed: 06/06/2024] Open
Abstract
The mitochondrial genomes of D. melacanthus and D. furcatus were sequenced and used to investigate the phylogenetic relationships with 54 species of Pentatomidae. Their mitogenomes are 17,197 and 15,444 bp-long, respectively, including 13 protein-coding genes (PCGs), 2 ribosomal RNA genes, and 22/21 transfer RNA genes, with conserved gene arrangement. Leu, Lys, and Ser were the most common amino acids in their PCGs. PCGs evolutionary analysis indicated their mitogenomes are under purifying selection, and the most conserved genes are from the cytochrome complex, reinforcing their suitability as markers for molecular taxonomy. We identified 490 mtSSRs in 56 Pentatomidae species, with large variation and a positive correlation between mtSSR number and genome size. Three mtSSRs were identified in each Diceraeus species. Only the mtSSR in the nad6 (D. melacanthus) and nad4 (D. furcatus) appear to have application as molecular markers for species characterization. Phylogenetic analysis confirmed the monophyly of Pentatomidae. However, our analysis challenged the monophyly of Pentatominae and Podopinae. We also detected unexpected relationships among some tribes and genera, highlighting the complexity of the internal taxonomic structure of Pentatomidae. Both Diceraeus species were grouped in the same clade with the remaining Carpocorini analyzed.
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Affiliation(s)
- Lilian Cris Dallagnol
- Insect Interactions Laboratory, Luiz de Queiroz College of Agriculture, University of São Paulo, Piracicaba, SP, Brazil
| | - Fernando Luís Cônsoli
- Insect Interactions Laboratory, Luiz de Queiroz College of Agriculture, University of São Paulo, Piracicaba, SP, Brazil.
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3
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Steenwyk JL, King N. The promise and pitfalls of synteny in phylogenomics. PLoS Biol 2024; 22:e3002632. [PMID: 38768403 PMCID: PMC11105162 DOI: 10.1371/journal.pbio.3002632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2024] Open
Abstract
Reconstructing the tree of life remains a central goal in biology. Early methods, which relied on small numbers of morphological or genetic characters, often yielded conflicting evolutionary histories, undermining confidence in the results. Investigations based on phylogenomics, which use hundreds to thousands of loci for phylogenetic inquiry, have provided a clearer picture of life's history, but certain branches remain problematic. To resolve difficult nodes on the tree of life, 2 recent studies tested the utility of synteny, the conserved collinearity of orthologous genetic loci in 2 or more organisms, for phylogenetics. Synteny exhibits compelling phylogenomic potential while also raising new challenges. This Essay identifies and discusses specific opportunities and challenges that bear on the value of synteny data and other rare genomic changes for phylogenomic studies. Synteny-based analyses of highly contiguous genome assemblies mark a new chapter in the phylogenomic era and the quest to reconstruct the tree of life.
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Affiliation(s)
- Jacob L. Steenwyk
- Howard Hughes Medical Institute, University of California, Berkeley, California, United States of America
- Department of Molecular and Cell Biology, University of California, Berkeley, California, United States of America
| | - Nicole King
- Howard Hughes Medical Institute, University of California, Berkeley, California, United States of America
- Department of Molecular and Cell Biology, University of California, Berkeley, California, United States of America
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4
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Leria M, Requin M, Le Bivic A, Pasini A. The placozoan Trichoplax. Nat Methods 2024; 21:543-545. [PMID: 38609555 DOI: 10.1038/s41592-024-02228-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/14/2024]
Affiliation(s)
- Marvin Leria
- Aix Marseille Université, CNRS, IBDM-UMR7288, Turing Centre for Living Systems, Marseille, France
| | - Magali Requin
- Aix Marseille Université, CNRS, IBDM-UMR7288, Turing Centre for Living Systems, Marseille, France
| | - André Le Bivic
- Aix Marseille Université, CNRS, IBDM-UMR7288, Turing Centre for Living Systems, Marseille, France
| | - Andrea Pasini
- Aix Marseille Université, CNRS, IBDM-UMR7288, Turing Centre for Living Systems, Marseille, France.
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5
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Benvenuto G, Leone S, Astoricchio E, Bormke S, Jasek S, D'Aniello E, Kittelmann M, McDonald K, Hartenstein V, Baena V, Escrivà H, Bertrand S, Schierwater B, Burkhardt P, Ruiz-Trillo I, Jékely G, Ullrich-Lüter J, Lüter C, D'Aniello S, Arnone MI, Ferraro F. Evolution of the ribbon-like organization of the Golgi apparatus in animal cells. Cell Rep 2024; 43:113791. [PMID: 38428420 DOI: 10.1016/j.celrep.2024.113791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 10/31/2023] [Accepted: 01/29/2024] [Indexed: 03/03/2024] Open
Abstract
The "ribbon," a structural arrangement in which Golgi stacks connect to each other, is considered to be restricted to vertebrate cells. Although ribbon disruption is linked to various human pathologies, its functional role in cellular processes remains unclear. In this study, we investigate the evolutionary origin of the Golgi ribbon. We observe a ribbon-like architecture in the cells of several metazoan taxa suggesting its early emergence in animal evolution predating the appearance of vertebrates. Supported by AlphaFold2 modeling, we propose that the evolution of Golgi reassembly and stacking protein (GRASP) binding by golgin tethers may have driven the joining of Golgi stacks resulting in the ribbon-like configuration. Additionally, we find that Golgi ribbon assembly is a shared developmental feature of deuterostomes, implying a role in embryogenesis. Overall, our study points to the functional significance of the Golgi ribbon beyond vertebrates and underscores the need for further investigations to unravel its elusive biological roles.
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Affiliation(s)
- Giovanna Benvenuto
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn (SZN), Naples, Italy
| | - Serena Leone
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn (SZN), Naples, Italy
| | - Emanuele Astoricchio
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn (SZN), Naples, Italy
| | | | - Sanja Jasek
- Living Systems Institute, University of Exeter, Exeter, UK; Heidelberg University, Centre for Organismal Studies (COS), Heidelberg, Germany
| | - Enrico D'Aniello
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn (SZN), Naples, Italy
| | - Maike Kittelmann
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, UK
| | - Kent McDonald
- Electron Microscope Lab, University of California Berkeley, Berkeley, CA, USA
| | - Volker Hartenstein
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, Los Angeles, CA, USA
| | - Valentina Baena
- Department of Cell Biology, UConn Health, Farmington, CT, USA
| | - Héctor Escrivà
- Sorbonne Université, CNRS, Biologie Intégrative des Organismes Marins, BIOM, Banyuls-sur-Mer, France
| | - Stephanie Bertrand
- Sorbonne Université, CNRS, Biologie Intégrative des Organismes Marins, BIOM, Banyuls-sur-Mer, France
| | - Bernd Schierwater
- Institute of Ecology and Evolution, Hannover University of Veterinary Medicine Foundation, Hannover, Germany
| | | | - Iñaki Ruiz-Trillo
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta, Barcelona, Spain; ICREA, Barcelona, Spain
| | - Gáspár Jékely
- Living Systems Institute, University of Exeter, Exeter, UK; Heidelberg University, Centre for Organismal Studies (COS), Heidelberg, Germany
| | | | | | - Salvatore D'Aniello
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn (SZN), Naples, Italy
| | - Maria Ina Arnone
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn (SZN), Naples, Italy
| | - Francesco Ferraro
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn (SZN), Naples, Italy.
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6
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Romanova DY, Moroz LL. Brief History of Placozoa. Methods Mol Biol 2024; 2757:103-122. [PMID: 38668963 DOI: 10.1007/978-1-0716-3642-8_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2024]
Abstract
Placozoans are morphologically the simplest free-living animals. They represent a unique window of opportunities to understand both the origin of the animal organization and the rules of life for the system and synthetic biology of the future. However, despite more than 100 years of their investigations, we know little about their organization, natural habitats, and life strategies. Here, we introduce this unique animal phylum and highlight some directions vital to broadening the frontiers of the biomedical sciences. In particular, understanding the genomic bases of placozoan biodiversity, cell identity, connectivity, reproduction, and cellular bases of behavior are critical hot spots for future studies.
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Affiliation(s)
- Daria Y Romanova
- Institute of Higher Nervous Activity and Neurophysiology of RAS, Moscow, Russian Federation.
| | - Leonid L Moroz
- Department of Neuroscience and McKnight Brain Institute, University of Florida, Gainesville, FL, USA.
- Whitney Laboratory for Marine Biosciences University of Florida, St. Augustine, FL, USA.
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7
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Zhang K, Qin Y, Sun W, Shi H, Zhao S, He L, Li C, Zhao J, Pan J, Wang G, Han Z, Zhao C, Yang X. Phylogenomic Analysis of Cytochrome P450 Gene Superfamily and Their Association with Flavonoids Biosynthesis in Peanut ( Arachis hypogaea L.). Genes (Basel) 2023; 14:1944. [PMID: 37895293 PMCID: PMC10606413 DOI: 10.3390/genes14101944] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 10/10/2023] [Accepted: 10/13/2023] [Indexed: 10/29/2023] Open
Abstract
Cytochrome P450s (CYPs) constitute extensive enzyme superfamilies in the plants, playing pivotal roles in a multitude of biosynthetic and detoxification pathways essential for growth and development, such as the flavonoid biosynthesis pathway. However, CYPs have not yet been systematically studied in the cultivated peanuts (Arachis hypogaea L.), a globally significant cash crop. This study addresses this knowledge deficit through a comprehensive genome-wide analysis, leading to the identification of 589 AhCYP genes in peanuts. Through phylogenetic analysis, all AhCYPs were systematically classified into 9 clans, 43 gene families. The variability in the number of gene family members suggests specialization in biological functions. Intriguingly, both tandem duplication and fragment duplication events have emerged as pivotal drivers in the evolutionary expansion of the AhCYP superfamily. Ka/Ks analysis underscored the substantial influence of strong purifying selection on the evolution of AhCYPs. Furthermore, we selected 21 genes encoding 8 enzymes associated with the flavonoid pathway. The results of quantitative real-time PCR (qRT-PCR) experiments unveiled stage-specific expression patterns during the development of peanut testa, with discernible variations between pink and red testa. Importantly, we identified a direct correlation between gene expression levels and the accumulation of metabolites. These findings offer valuable insights into elucidating the comprehensive functions of AhCYPs and the underlying mechanisms governing the divergent accumulation of flavonoids in testa of different colors.
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Affiliation(s)
- Kun Zhang
- College of Agricultural Science and Technology, Shandong Agriculture and Engineering University, Jinan 250100, China; (K.Z.); (Y.Q.); (J.Z.)
- Institute of Crop Germplasm Resources (Institute of Biotechnology), Shandong Academy of Agricultural Sciences, Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Jinan 250100, China; (S.Z.); (C.L.); (J.P.); (G.W.); (C.Z.)
| | - Yongmei Qin
- College of Agricultural Science and Technology, Shandong Agriculture and Engineering University, Jinan 250100, China; (K.Z.); (Y.Q.); (J.Z.)
| | - Wei Sun
- Linyi Academy of Agricultural Sciences, Linyi 276003, China;
| | - Hourui Shi
- Shandong Seed Management Station, Jinan 250100, China;
| | - Shuzhen Zhao
- Institute of Crop Germplasm Resources (Institute of Biotechnology), Shandong Academy of Agricultural Sciences, Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Jinan 250100, China; (S.Z.); (C.L.); (J.P.); (G.W.); (C.Z.)
| | - Liangqiong He
- Cash Crop Research Institute, Guangxi Academy of Agricultural Sciences, Nanning 530007, China; (L.H.); (Z.H.)
| | - Changsheng Li
- Institute of Crop Germplasm Resources (Institute of Biotechnology), Shandong Academy of Agricultural Sciences, Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Jinan 250100, China; (S.Z.); (C.L.); (J.P.); (G.W.); (C.Z.)
| | - Jin Zhao
- College of Agricultural Science and Technology, Shandong Agriculture and Engineering University, Jinan 250100, China; (K.Z.); (Y.Q.); (J.Z.)
| | - Jiaowen Pan
- Institute of Crop Germplasm Resources (Institute of Biotechnology), Shandong Academy of Agricultural Sciences, Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Jinan 250100, China; (S.Z.); (C.L.); (J.P.); (G.W.); (C.Z.)
| | - Guanghao Wang
- Institute of Crop Germplasm Resources (Institute of Biotechnology), Shandong Academy of Agricultural Sciences, Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Jinan 250100, China; (S.Z.); (C.L.); (J.P.); (G.W.); (C.Z.)
| | - Zhuqiang Han
- Cash Crop Research Institute, Guangxi Academy of Agricultural Sciences, Nanning 530007, China; (L.H.); (Z.H.)
| | - Chuanzhi Zhao
- Institute of Crop Germplasm Resources (Institute of Biotechnology), Shandong Academy of Agricultural Sciences, Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Jinan 250100, China; (S.Z.); (C.L.); (J.P.); (G.W.); (C.Z.)
| | - Xiangli Yang
- College of Agricultural Science and Technology, Shandong Agriculture and Engineering University, Jinan 250100, China; (K.Z.); (Y.Q.); (J.Z.)
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8
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Zheng Q, Daskalov A. Microbial gasdermins: More than a billion years of pyroptotic-like cell death. Semin Immunol 2023; 69:101813. [PMID: 37480832 DOI: 10.1016/j.smim.2023.101813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 07/16/2023] [Accepted: 07/17/2023] [Indexed: 07/24/2023]
Abstract
In the recent past, the concept of immunity has been extended to eukaryotic and prokaryotic microorganisms, like fungi and bacteria. The latest findings have drawn remarkable evolutionary parallels between metazoan and microbial defense-related genes, unveiling a growing number of shared transkingdom components of immune systems. One such component is the gasdermin family of pore-forming proteins - executioners of a highly inflammatory immune cell death program in mammals, termed pyroptosis. Pyroptotic cell death limits the spread of intracellular pathogens by eliminating infected cells and coordinates the broader inflammatory response to infection. The microbial gasdermins have similarly been implicated in defense-related cell death reactions in fungi, bacteria and archaea. Moreover, the discovery of the molecular regulators of gasdermin cytotoxicity in fungi and bacteria, has established additional evolutionary links to mammalian pyroptotic pathways. Here, we focus on the gasdermin proteins in microorganisms and their role in organismal defense and provide perspective on this remarkable case study in comparative immunology.
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Affiliation(s)
- Qi Zheng
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Asen Daskalov
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China; ImmunoConcEpT, CNRS UMR 5164, University of Bordeaux, Bordeaux, France.
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9
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Olegovna LA, Alexandrovna VE, Sergeevna KA, Vasilievich MY, Alexandrovich SA. Aldolase of Mytilus galloprovincialis, Lamarck, 1819: Gene structure, tissue specificity of expression level and activity. Comp Biochem Physiol B Biochem Mol Biol 2023; 267:110862. [PMID: 37146868 DOI: 10.1016/j.cbpb.2023.110862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 04/25/2023] [Accepted: 05/02/2023] [Indexed: 05/07/2023]
Abstract
In the present study, the structure of the fructose-1,6-bisphosphataldolase (FBA) gene in Mytilus galloprovincialis (Lamarck, 1819) was analyzed and its tissue specificity of expression level and activity was determined. A 1092 base pairs (bps) complete coding sequence of the FBA gene was assembled from M. galloprovincialis transcriptome. Only one gene encoding FBA (MgFBA) was identified in the M. galloprovincialis genome. The length of MgFBA was 363 amino acids with a molecular mass of 39.7 kDa. According to the amino acid residues, the detected MgFBA gene is a type I aldolase. The FBA gene in M. galloprovincialis had 7 exons; the maximum intron length was about 2.5 kbps. Intraspecific nucleotide diversity (15 mutations) between MgFBAs from the Mediterranean mussels and the Black Sea mussels (present study) was detected. All mutations were synonymous. Tissue specificity in FBA expression level and activity was established. No direct correlation between these functions was found. The highest level of FBA gene expression is found in muscle tissue. According to the phylogenetic analyses, FBA gene in invertebrates could be considered the ancestral gene of muscle type aldolase, which may explain the character of tissue-specific expression.
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Affiliation(s)
| | - Vodiasova Ekaterina Alexandrovna
- Federal Research Center «Institute of Biology of Southern Seas RAS», Department Animal Physiology and Biochemistry, Moscow office: 38 Leninsky Ave., Moscow 119991, Russia; Sevastopol State University, Physic Department, 33 Universitetskaya Str., Sevastopol 299053, Russia
| | - Kokhan Alena Sergeevna
- Federal Research Center «Institute of Biology of Southern Seas RAS», Department Animal Physiology and Biochemistry, Moscow office: 38 Leninsky Ave., Moscow 119991, Russia
| | - Meger Yakov Vasilievich
- Sevastopol State University, Physic Department, 33 Universitetskaya Str., Sevastopol 299053, Russia
| | - Soldatov Alexander Alexandrovich
- Federal Research Center «Institute of Biology of Southern Seas RAS», Department Animal Physiology and Biochemistry, Moscow office: 38 Leninsky Ave., Moscow 119991, Russia; Sevastopol State University, Physic Department, 33 Universitetskaya Str., Sevastopol 299053, Russia
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10
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Tessler M, Neumann JS, Kamm K, Osigus HJ, Eshel G, Narechania A, Burns JA, DeSalle R, Schierwater B. Phylogenomics and the first higher taxonomy of Placozoa, an ancient and enigmatic animal phylum. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.1016357] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Placozoa is an ancient phylum of extraordinarily unusual animals: miniscule, ameboid creatures that lack most fundamental animal features. Despite high genetic diversity, only recently have the second and third species been named. While prior genomic studies suffer from incomplete placozoan taxon sampling, we more than double the count with protein sequences from seven key genomes and produce the first nuclear phylogenomic reconstruction of all major placozoan lineages. This leads us to the first complete Linnaean taxonomic classification of Placozoa, over a century after its discovery: This may be the only time in the 21st century when an entire higher taxonomy for a whole animal phylum is formalized. Our classification establishes 2 new classes, 4 new orders, 3 new families, 1 new genus, and 1 new species, namely classes Polyplacotomia and Uniplacotomia; orders Polyplacotomea, Trichoplacea, Cladhexea, and Hoilungea; families Polyplacotomidae, Cladtertiidae, and Hoilungidae; and genus Cladtertia with species Cladtertia collaboinventa, nov. Our likelihood and gene content tree topologies refine the relationships determined in previous studies. Adding morphological data into our phylogenomic matrices suggests sponges (Porifera) as the sister to other animals, indicating that modest data addition shifts this node away from comb jellies (Ctenophora). Furthermore, by adding the first genomic protein data of the exceptionally distinct and branching Polyplacotoma mediterranea, we solidify its position as sister to all other placozoans; a divergence we estimate to be over 400 million years old. Yet even this deep split sits on a long branch to other animals, suggesting a bottleneck event followed by diversification. Ancestral state reconstructions indicate large shifts in gene content within Placozoa, with Hoilungia hongkongensis and its closest relatives having the most unique genetics.
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11
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Li Y, Wang S, Chen J, Zhou J, Bu W. Two new stick insect species of Sosibia Stål (Phasmatodea: Lonchodidae: Necrosciinae) from China and the first report on mitochondrial genomes of this genus. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2022; 111:e21901. [PMID: 35368111 DOI: 10.1002/arch.21901] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 03/19/2022] [Accepted: 03/22/2022] [Indexed: 06/14/2023]
Abstract
We describe and illustrate two new species of Sosibia from China: Sosibia gibba sp. nov. and Sosibia ovata sp. nov. This report includes a key to Sosibia species from China and a description of the distribution area in China. The two mitochondrial genomes of these new Sosibia species were sequenced and annotated for the first time. The compositional biases, codon usage, nucleotide composition, and construct tRNA secondary structures of the two mitogenomes were analyzed. The phylogenetic relationships based on the mitogenomes using Bayesian inference and maximum likelihood methods supported the monophyly of Necrosciinae and divided it into two distinct clades: A: (Sipyloidea + [Sosibia + Calvisia]); and B: (Neohirasea + Micadina).
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Affiliation(s)
- Yanfei Li
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China
| | - Shujing Wang
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China
| | - Juhong Chen
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China
| | - Jiayue Zhou
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China
| | - Wenjun Bu
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China
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12
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Novosolov M, Yahalomi D, Chang ES, Fiala I, Cartwright P, Huchon D. The Phylogenetic Position of the Enigmatic, Polypodium hydriforme (Cnidaria, Polypodiozoa): Insights from Mitochondrial Genomes. Genome Biol Evol 2022; 14:6648524. [PMID: 35867352 PMCID: PMC9380995 DOI: 10.1093/gbe/evac112] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/13/2022] [Indexed: 11/13/2022] Open
Abstract
Polypodium hydriforme is an enigmatic parasite that belongs to the phylum Cnidaria. Its taxonomic position has been debated: whereas it was previously suggested to be part of Medusozoa, recent phylogenomic analyses based on nuclear genes support the view that P. hydriforme and Myxozoa form a clade called Endocnidozoa. Medusozoans have linear mitochondrial (mt) chromosomes, whereas myxozoans, as most metazoan species, have circular chromosomes. In this work, we determined the structure of the mt genome of P. hydriforme, using Illumina and Oxford Nanopore Technologies reads, and showed that it is circular. This suggests that P. hydriforme is not nested within Medusozoa, as this would entail linearization followed by recirculation. Instead, our results support the view that P. hydriforme is a sister clade to Myxozoa, and mt linearization in the lineage leading to medusozoans occurred after the divergence of Myxozoa + P. hydriforme. Detailed analyses of the assembled P. hydriforme mt genome show that: (1) it is encoded on a single circular chromosome with an estimated size of ∼93,000 base pairs, making it one of the largest metazoan mt genomes; (2) around 78% of the genome encompasses a noncoding region composed of several repeat types; (3) similar to Myxozoa, no mt tRNAs were identified; (4) the codon TGA is a stop codon and does not encode for tryptophan as in other cnidarians; (5) similar to myxozoan mt genomes, it is extremely fast evolving.
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Affiliation(s)
- Maria Novosolov
- School of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Dayana Yahalomi
- School of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel
| | - E Sally Chang
- Department of Ecology and Evolutionary Biology, University of Kansas, 1200 Sunnyside Avenue, Haworth Hall, Lawrence, KS, 66045, USA.,Computational and Statistical Genomics Branch, Division of Intramural Research, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ivan Fiala
- Institute of Parasitology, Biology Centre, Academy of Sciences of the Czech Republic, Branišovská 31, 370 05 České Budĕjovice, Czech Republic.,Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budĕjovice, Czech Republic
| | - Paulyn Cartwright
- Department of Ecology and Evolutionary Biology, University of Kansas, 1200 Sunnyside Avenue, Haworth Hall, Lawrence, KS, 66045, USA
| | - Dorothée Huchon
- School of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel.,The Steinhardt Museum of Natural History and National Research Center, Tel Aviv University, Tel Aviv 6997801, Israel
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13
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Unprecedented frequency of mitochondrial introns in colonial bilaterians. Sci Rep 2022; 12:10889. [PMID: 35764672 PMCID: PMC9240083 DOI: 10.1038/s41598-022-14477-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 06/07/2022] [Indexed: 11/16/2022] Open
Abstract
Animal mitogenomes are typically devoid of introns. Here, we report the largest number of mitochondrial introns ever recorded from bilaterian animals. Mitochondrial introns were identified for the first time from the phylum Bryozoa. They were found in four species from three families (Order Cheilostomatida). A total of eight introns were found in the complete mitogenome of Exechonella vieirai, and five, 17 and 18 introns were found in the partial mitogenomes of Parantropora penelope, Discoporella cookae and Cupuladria biporosa, respectively. Intron-encoded protein domains reverse transcriptase and intron maturase (RVT-IM) were identified in all species. Introns in E. vieirai and P. penelope had conserved Group II intron ribozyme domains V and VI. Conserved domains were lacking from introns in D. cookae and C. biporosa, preventing their further categorization. Putative origins of metazoan introns were explored in a phylogenetic context, using an up-to-date alignment of mitochondrial RVT-IM domains. Results confirmed previous findings of multiple origins of annelid, placozoan and sponge RVT-IM domains and provided evidence for common intron donor sources across metazoan phyla. Our results corroborate growing evidence that some metazoans with regenerative abilities (i.e. placozoans, sponges, annelids and bryozoans) are susceptible to intron integration, most likely via horizontal gene transfer.
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14
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Wang C, Ye P, Liu M, Zhang Y, Feng H, Liu J, Zhou H, Wang J, Chen X. Comparative Analysis of Four Complete Mitochondrial Genomes of Epinephelidae (Perciformes). Genes (Basel) 2022; 13:genes13040660. [PMID: 35456466 PMCID: PMC9029768 DOI: 10.3390/genes13040660] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 03/28/2022] [Accepted: 04/04/2022] [Indexed: 01/19/2023] Open
Abstract
Groupers are commercial, mainly reef-associated fishes, classified in the family Epinephelidae (Perciformes). This study first sequenced the complete mitogenomes of Cephalopholis leopardus, Cephalopholis spiloparaea, Epinephelus amblycephalus, and Epinephelus hexagonatus. The lengths of the four Epinephelidae mitogenomes ranged from 16,585 base pair (bp) to 16,872 bp with the typical gene order. All tRNA genes had a typical cloverleaf structure, except the tRNA-Ser (AGY) gene which was lacking the entire dihydrouridine arm. The ratio of nonsynonymous substitution (Ka) and synonymous substitution (Ks) indicated that four groupers were suffering a purifying selection. Phylogenetic relationships were reconstructed by Bayesian inference (BI) and maximum likelihood (ML) methods based on all mitogenomic data of 41 groupers and 2 outgroups. The identical topologies result with high support values showed that Cephalopholis and Epinephelus are not monophyletic genera. Anyperodon and Cromileptes clustered to Epinephelus. Aethaloperca rogaa and Cephalopholis argus assembled a clad. Cephalopholis leopardus, C. spiloparaea, and Cephalopholis miniata are also in a clade. Epinephelushexagonatus is close to Epinephelus tauvina and Epinephelus merra, and E. amblycephalus is a sister group with Epinephelus stictus. More mitogenomic data from Epinephelidae species are essential to understand its taxonomic status with the family Serranidae.
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Affiliation(s)
- Chen Wang
- College of Marine Sciences, South China Agriculture University, Guangzhou 510642, China; (C.W.); (P.Y.); (Y.Z.); (H.F.); (J.L.)
| | - Peiyuan Ye
- College of Marine Sciences, South China Agriculture University, Guangzhou 510642, China; (C.W.); (P.Y.); (Y.Z.); (H.F.); (J.L.)
- College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China
| | - Min Liu
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361012, China;
| | - Yue Zhang
- College of Marine Sciences, South China Agriculture University, Guangzhou 510642, China; (C.W.); (P.Y.); (Y.Z.); (H.F.); (J.L.)
| | - Haiqing Feng
- College of Marine Sciences, South China Agriculture University, Guangzhou 510642, China; (C.W.); (P.Y.); (Y.Z.); (H.F.); (J.L.)
| | - Jingyu Liu
- College of Marine Sciences, South China Agriculture University, Guangzhou 510642, China; (C.W.); (P.Y.); (Y.Z.); (H.F.); (J.L.)
| | - Haolang Zhou
- Guangxi Mangrove Research Center, Beihai 536000, China;
| | - Junjie Wang
- Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, School of Life Sciences, South China Normal University, Guangzhou 510631, China
- Correspondence: (J.W.); (X.C.); Tel.: +86-137-9817-8534 (J.W.); +86-139-2210-4624 (X.C.)
| | - Xiao Chen
- College of Marine Sciences, South China Agriculture University, Guangzhou 510642, China; (C.W.); (P.Y.); (Y.Z.); (H.F.); (J.L.)
- Guangxi Mangrove Research Center, Beihai 536000, China;
- Correspondence: (J.W.); (X.C.); Tel.: +86-137-9817-8534 (J.W.); +86-139-2210-4624 (X.C.)
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15
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Kobayashi G, Itoh H, Kojima S. Mitogenome of a stink worm (Annelida: Travisiidae) includes degenerate group II intron that is also found in five congeneric species. Sci Rep 2022; 12:4449. [PMID: 35292662 PMCID: PMC8924214 DOI: 10.1038/s41598-022-08103-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 02/25/2022] [Indexed: 12/05/2022] Open
Abstract
Mitogenomes are useful for inferring phylogenetic relationships between organisms. Although the mitogenomes of Annelida, one of the most morphologically and ecologically diverse metazoan groups have been well sequenced, those of several families remain unexamined. This study determined the first mitogenome from the family Travisiidae (Travisia sanrikuensis), analyzed its mitogenomic features, and reconstructed a phylogeny of Sedentaria. The monophyly of the Terebellida + Arenicolida + Travisiidae clade is supported by molecular phylogenetic analysis. The placement of Travisiidae is unclear because of the lack of mitogenomes from closely related lineages. An unexpected intron appeared within the cox1 gene of T. sanrikuensis and in the same positions of five undescribed Travisia spp. Although the introns are shorter (790–1386 bp) than other group II introns, they can be considered degenerate group II introns due to type II intron maturase open reading frames, found in two of the examined species, and motifs characteristic of group II introns. This is likely the first known case in metazoans where mitochondrial group II introns obtained by a common ancestor are conserved in several descendants. Insufficient evolutionary time for intron loss in Travisiidae, or undetermined mechanisms may have helped maintain the degenerate introns.
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Affiliation(s)
- Genki Kobayashi
- Seto Marine Biological Laboratory, Field Science Education and Research Center, Kyoto University, 459 Shirahama, Nishimuro, Wakayama, 649-2211, Japan.
| | - Hajime Itoh
- National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan
| | - Shigeaki Kojima
- Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8564, Japan
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16
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Abdel-Gaber R, Alajmi R, Haddadi R. Identifying two moth species (Lepidoptera: Ditrysia) from Saudi Arabia using mitochondrial 16S rRNA sequences. Saudi J Biol Sci 2021; 28:7253-7256. [PMID: 34867029 PMCID: PMC8626258 DOI: 10.1016/j.sjbs.2021.08.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Revised: 06/28/2021] [Accepted: 08/10/2021] [Indexed: 11/10/2022] Open
Abstract
The mitochondrial genetic markers are considered useful tools for discrimination between more closely related lepidopteran taxa. Therefore, the present study aimed to investigate the role of mitochondrial (mt) 16 s rRNA gene in the determination of the taxonomic position for two moth species within Ditrysia clade. Maximum likelihood analysis has indicated a well-supported dendrogram based on the Tamura-Nei model for the recovered lepidopterans. The mt 16 s rRNA query sequences from 24 species within seven families were analyzed. This analysis and bootstrap confidence revealed two major clades representing Glossata suborder within Lepidoptera, with a close relationship of Noctuoidea + (Pyraloidea (Hesperioidea + Papilionoidea)). The subfamily Heliothinae forming a sister group with Risobinae (Noctinae + Hadeninae). In addition, there is a clear observation about the close relation between Phycitinae + Galleriinae within Pyraloidea and Cyrestinae + Limenitidinae within Papilionoidea. The present study supported that the Helicoverpa and Meroptera species are the first accounts of these genera inhabiting Saudi Arabia.
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Affiliation(s)
- Rewaida Abdel-Gaber
- Department of Zoology, College of Science, King Saud University, P.O. Box 145111, Riyadh, Saudi Arabia
| | - Reem Alajmi
- Department of Zoology, College of Science, King Saud University, P.O. Box 145111, Riyadh, Saudi Arabia
| | - Rania Haddadi
- Department of Zoology, College of Science, King Saud University, P.O. Box 145111, Riyadh, Saudi Arabia
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17
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Schierwater B, Osigus HJ, Bergmann T, Blackstone NW, Hadrys H, Hauslage J, Humbert PO, Kamm K, Kvansakul M, Wysocki K, DeSalle R. The enigmatic Placozoa part 2: Exploring evolutionary controversies and promising questions on earth and in space. Bioessays 2021; 43:e2100083. [PMID: 34490659 DOI: 10.1002/bies.202100083] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 07/21/2021] [Accepted: 08/16/2021] [Indexed: 12/28/2022]
Abstract
The placozoan Trichoplax adhaerens has been bridging gaps between research disciplines like no other animal. As outlined in part 1, placozoans have been subject of hot evolutionary debates and placozoans have challenged some fundamental evolutionary concepts. Here in part 2 we discuss the exceptional genetics of the phylum Placozoa and point out some challenging model system applications for the best known species, Trichoplax adhaerens.
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Affiliation(s)
- Bernd Schierwater
- Institute of Animal Ecology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Hans-Jürgen Osigus
- Institute of Animal Ecology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Tjard Bergmann
- Institute of Animal Ecology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Neil W Blackstone
- Department of Biological Sciences, Northern Illinois University, DeKalb, Illinois, USA
| | - Heike Hadrys
- Institute of Animal Ecology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Jens Hauslage
- Gravitational Biology, Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany
| | - Patrick O Humbert
- Department of Biochemistry & Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia.,Research Centre for Molecular Cancer Prevention, La Trobe University, Melbourne, Victoria, Australia
| | - Kai Kamm
- Institute of Animal Ecology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Marc Kvansakul
- Department of Biochemistry & Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia.,Research Centre for Molecular Cancer Prevention, La Trobe University, Melbourne, Victoria, Australia
| | - Kathrin Wysocki
- Institute of Animal Ecology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Rob DeSalle
- American Museum of Natural History, New York, New York, USA
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18
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Mukhopadhyay J, Hausner G. Organellar Introns in Fungi, Algae, and Plants. Cells 2021; 10:cells10082001. [PMID: 34440770 PMCID: PMC8393795 DOI: 10.3390/cells10082001] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/31/2021] [Accepted: 08/05/2021] [Indexed: 12/16/2022] Open
Abstract
Introns are ubiquitous in eukaryotic genomes and have long been considered as ‘junk RNA’ but the huge energy expenditure in their transcription, removal, and degradation indicate that they may have functional significance and can offer evolutionary advantages. In fungi, plants and algae introns make a significant contribution to the size of the organellar genomes. Organellar introns are classified as catalytic self-splicing introns that can be categorized as either Group I or Group II introns. There are some biases, with Group I introns being more frequently encountered in fungal mitochondrial genomes, whereas among plants Group II introns dominate within the mitochondrial and chloroplast genomes. Organellar introns can encode a variety of proteins, such as maturases, homing endonucleases, reverse transcriptases, and, in some cases, ribosomal proteins, along with other novel open reading frames. Although organellar introns are viewed to be ribozymes, they do interact with various intron- or nuclear genome-encoded protein factors that assist in the intron RNA to fold into competent splicing structures, or facilitate the turn-over of intron RNAs to prevent reverse splicing. Organellar introns are also known to be involved in non-canonical splicing, such as backsplicing and trans-splicing which can result in novel splicing products or, in some instances, compensate for the fragmentation of genes by recombination events. In organellar genomes, Group I and II introns may exist in nested intronic arrangements, such as introns within introns, referred to as twintrons, where splicing of the external intron may be dependent on splicing of the internal intron. These nested or complex introns, with two or three-component intron modules, are being explored as platforms for alternative splicing and their possible function as molecular switches for modulating gene expression which could be potentially applied towards heterologous gene expression. This review explores recent findings on organellar Group I and II introns, focusing on splicing and mobility mechanisms aided by associated intron/nuclear encoded proteins and their potential roles in organellar gene expression and cross talk between nuclear and organellar genomes. Potential application for these types of elements in biotechnology are also discussed.
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MESH Headings
- Evolution, Molecular
- Gene Expression Regulation, Fungal
- Gene Expression Regulation, Plant
- Genome, Fungal
- Genome, Plant
- Introns
- Organelles/genetics
- Organelles/metabolism
- RNA Splicing
- RNA Stability
- RNA, Algal/genetics
- RNA, Algal/metabolism
- RNA, Fungal/genetics
- RNA, Fungal/metabolism
- RNA, Plant/genetics
- RNA, Plant/metabolism
- RNA, Untranslated/genetics
- RNA, Untranslated/metabolism
- Transcription, Genetic
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19
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Mitochondrial Genomic Landscape: A Portrait of the Mitochondrial Genome 40 Years after the First Complete Sequence. Life (Basel) 2021; 11:life11070663. [PMID: 34357035 PMCID: PMC8303319 DOI: 10.3390/life11070663] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/02/2021] [Accepted: 07/03/2021] [Indexed: 12/11/2022] Open
Abstract
Notwithstanding the initial claims of general conservation, mitochondrial genomes are a largely heterogeneous set of organellar chromosomes which displays a bewildering diversity in terms of structure, architecture, gene content, and functionality. The mitochondrial genome is typically described as a single chromosome, yet many examples of multipartite genomes have been found (for example, among sponges and diplonemeans); the mitochondrial genome is typically depicted as circular, yet many linear genomes are known (for example, among jellyfish, alveolates, and apicomplexans); the chromosome is normally said to be “small”, yet there is a huge variation between the smallest and the largest known genomes (found, for example, in ctenophores and vascular plants, respectively); even the gene content is highly unconserved, ranging from the 13 oxidative phosphorylation-related enzymatic subunits encoded by animal mitochondria to the wider set of mitochondrial genes found in jakobids. In the present paper, we compile and describe a large database of 27,873 mitochondrial genomes currently available in GenBank, encompassing the whole eukaryotic domain. We discuss the major features of mitochondrial molecular diversity, with special reference to nucleotide composition and compositional biases; moreover, the database is made publicly available for future analyses on the MoZoo Lab GitHub page.
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20
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Kuznetsov AV, Vainer VI, Volkova YM, Kartashov LE. Motility disorders and disintegration into separate cells of Trichoplax sp. H2 in the presence of Zn 2+ ions and L-cysteine molecules: A systems approach. Biosystems 2021; 206:104444. [PMID: 34023485 DOI: 10.1016/j.biosystems.2021.104444] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 05/08/2021] [Accepted: 05/09/2021] [Indexed: 01/01/2023]
Abstract
Placozoa remain an ancient multicellular system with a dynamic body structure where calcium ions carry out a primary role in maintaining the integrity of the entire animal. Zinc ions can compete with calcium ions adsorption. We studied the effect of zinc ions and l-cysteine molecules on the interaction of Trichoplax sp. H2 cells. The regularity of formless motion was diminished in the presence of 20-25 μM of Zn2+ ions leading to the formation of branching animal forms. Locomotor ciliated cells moved chaotically and independently of each other leaving the Trichoplax body and opening a network of fiber cells. Application of 100 μM cysteine resulted in dissociation of the plate into separate cells. The combined chemical treatment shifted the effect in a random sample of animals toward disintegration, i.e. initially leading to disorder of collective cell movement and then to total body fragmentation. Two dissociation patterns of Trichoplax plate as "expanding ring" and "bicycle wheel" were revealed. Analysis of the interaction of Ca2+ and Zn2+ ions with cadherin showed that more than half (54%) of the amino acid residues with which Ca2+ and Zn2+ ions bind are common. The contact interaction of cells covered by the cadherin molecules is important for the coordinated movements of Trichoplax organism, while zinc ions are capable to break junctions between the cells. The involvement of other players, for example, l-cysteine in the regulation of Ca2+-dependent adhesion may be critical leading to the typical dissociation of Trichoplax body like in a calcium-free environment. A hypothesis about the essential role of calcium ions in the emergence of Metazoa ancestor is proposed.
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Affiliation(s)
- A V Kuznetsov
- A.O. Kovalevsky Institute of Biology of the Southern Seas RAS, Leninsky Avenue 38, Moscow, 119991, Russia.
| | - V I Vainer
- A.O. Kovalevsky Institute of Biology of the Southern Seas RAS, Leninsky Avenue 38, Moscow, 119991, Russia
| | - Yu M Volkova
- A.O. Kovalevsky Institute of Biology of the Southern Seas RAS, Leninsky Avenue 38, Moscow, 119991, Russia
| | - L E Kartashov
- A.O. Kovalevsky Institute of Biology of the Southern Seas RAS, Leninsky Avenue 38, Moscow, 119991, Russia
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21
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Neumann JS, Desalle R, Narechania A, Schierwater B, Tessler M. Morphological Characters Can Strongly Influence Early Animal Relationships Inferred from Phylogenomic Data Sets. Syst Biol 2021; 70:360-375. [PMID: 32462193 PMCID: PMC7875439 DOI: 10.1093/sysbio/syaa038] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 01/27/2020] [Accepted: 01/29/2020] [Indexed: 12/19/2022] Open
Abstract
There are considerable phylogenetic incongruencies between morphological and phylogenomic data for the deep evolution of animals. This has contributed to a heated debate over the earliest-branching lineage of the animal kingdom: the sister to all other Metazoa (SOM). Here, we use published phylogenomic data sets ($\sim $45,000-400,000 characters in size with $\sim $15-100 taxa) that focus on early metazoan phylogeny to evaluate the impact of incorporating morphological data sets ($\sim $15-275 characters). We additionally use small exemplar data sets to quantify how increased taxon sampling can help stabilize phylogenetic inferences. We apply a plethora of common methods, that is, likelihood models and their "equivalent" under parsimony: character weighting schemes. Our results are at odds with the typical view of phylogenomics, that is, that genomic-scale data sets will swamp out inferences from morphological data. Instead, weighting morphological data 2-10$\times $ in both likelihood and parsimony can in some cases "flip" which phylum is inferred to be the SOM. This typically results in the molecular hypothesis of Ctenophora as the SOM flipping to Porifera (or occasionally Placozoa). However, greater taxon sampling improves phylogenetic stability, with some of the larger molecular data sets ($>$200,000 characters and up to $\sim $100 taxa) showing node stability even with $\geqq100\times $ upweighting of morphological data. Accordingly, our analyses have three strong messages. 1) The assumption that genomic data will automatically "swamp out" morphological data is not always true for the SOM question. Morphological data have a strong influence in our analyses of combined data sets, even when outnumbered thousands of times by molecular data. Morphology therefore should not be counted out a priori. 2) We here quantify for the first time how the stability of the SOM node improves for several genomic data sets when the taxon sampling is increased. 3) The patterns of "flipping points" (i.e., the weighting of morphological data it takes to change the inferred SOM) carry information about the phylogenetic stability of matrices. The weighting space is an innovative way to assess comparability of data sets that could be developed into a new sensitivity analysis tool. [Metazoa; Morphology; Phylogenomics; Weighting.].
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Affiliation(s)
- Johannes S Neumann
- Richard Gilder Graduate School, American Museum of Natural History, New York, NY 10024, USA
- Division of Invertebrate Zoology, American Museum of Natural History, New York, NY 10024, USA
- Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, NY 10024, USA
| | - Rob Desalle
- Division of Invertebrate Zoology, American Museum of Natural History, New York, NY 10024, USA
- Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, NY 10024, USA
| | - Apurva Narechania
- Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, NY 10024, USA
| | - Bernd Schierwater
- Division of Invertebrate Zoology, American Museum of Natural History, New York, NY 10024, USA
- Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, NY 10024, USA
- ITZ, Division of Ecology and Evolution, Tierärztliche Hochschule Hannover, Bünteweg 9, 30559 Hannover, Germany
| | - Michael Tessler
- Division of Invertebrate Zoology, American Museum of Natural History, New York, NY 10024, USA
- Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, NY 10024, USA
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22
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Zhang J, Miao G, Hu S, Sun Q, Ding H, Ji Z, Guo P, Yan S, Wang C, Kan X, Nie L. Quantification and evolution of mitochondrial genome rearrangement in Amphibians. BMC Ecol Evol 2021; 21:19. [PMID: 33563214 PMCID: PMC7871395 DOI: 10.1186/s12862-021-01755-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Accepted: 01/28/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Rearrangement is an important topic in the research of amphibian mitochondrial genomes ("mitogenomes" hereafter), whose causes and mechanisms remain enigmatic. Globally examining mitogenome rearrangements and uncovering their characteristics can contribute to a better understanding of mitogenome evolution. RESULTS Here we systematically investigated mitogenome arrangements of 232 amphibians including four newly sequenced Dicroglossidae mitogenomes. The results showed that our new sequenced mitogenomes all possessed a trnM tandem duplication, which was not exclusive to Dicroglossidae. By merging the same arrangements, the mitogenomes of ~ 80% species belonged to the four major patterns, the major two of which were typical vertebrate arrangement and typical neobatrachian arrangement. Using qMGR for calculating rearrangement frequency (RF) (%), we found that the control region (CR) (RF = 45.04) and trnL2 (RF = 38.79) were the two most frequently rearranged components. Forty-seven point eight percentage of amphibians possessed rearranged mitogenomes including all neobatrachians and their distribution was significantly clustered in the phylogenetic trees (p < 0.001). In addition, we argued that the typical neobatrachian arrangement may have appeared in the Late Jurassic according to possible occurrence time estimation. CONCLUSION It was the first global census of amphibian mitogenome arrangements from the perspective of quantity statistics, which helped us to systematically understand the type, distribution, frequency and phylogenetic characteristics of these rearrangements.
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Affiliation(s)
- Jifeng Zhang
- School of Biological Engineering, Huainan Normal University, Huainan, Anhui, 232001, People's Republic of China.
- College of Life Science, Anhui Normal University, Wuhu, Anhui, 241000, People's Republic of China.
- Anhui Key Laboratory of Low Temperature Co-Fired Materials, Huainan Normal University, Huainan, 232001, People's Republic of China.
- Key Laboratory of Industrial Dust Prevention and Control and Occupational Health and Safety, Ministry of Education, Huainan, 232001, People's Republic of China.
- Anhui Shanhe Pharmaceutical Excipients Co., Ltd., Huainan, 232001, People's Republic of China.
| | - Guopen Miao
- School of Biological Engineering, Huainan Normal University, Huainan, Anhui, 232001, People's Republic of China
| | - Shunjie Hu
- School of Biological Engineering, Huainan Normal University, Huainan, Anhui, 232001, People's Republic of China
| | - Qi Sun
- School of Biological Engineering, Huainan Normal University, Huainan, Anhui, 232001, People's Republic of China
| | - Hengwu Ding
- College of Life Science, Anhui Normal University, Wuhu, Anhui, 241000, People's Republic of China
| | - Zhicheng Ji
- Department of Biostatistics, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, 21205, USA
| | - Pen Guo
- Life Science and Food Engineering College, Yibin University, Yibin, Sichuan, 644000, People's Republic of China
| | - Shoubao Yan
- School of Biological Engineering, Huainan Normal University, Huainan, Anhui, 232001, People's Republic of China
| | - Chengrun Wang
- School of Biological Engineering, Huainan Normal University, Huainan, Anhui, 232001, People's Republic of China
| | - Xianzhao Kan
- College of Life Science, Anhui Normal University, Wuhu, Anhui, 241000, People's Republic of China.
| | - Liuwang Nie
- College of Life Science, Anhui Normal University, Wuhu, Anhui, 241000, People's Republic of China.
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23
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Abdel-Gaber R, Alajmi R, Haddadi R, El-Ashram S. The phylogenetic position of Arhaphe deviatica within Hemipteran insects: A potential model species for eco-devo studies of symbiosis. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2020; 336:73-78. [PMID: 33351288 DOI: 10.1002/jez.b.23019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 12/02/2020] [Accepted: 12/08/2020] [Indexed: 11/06/2022]
Abstract
Insecta is known to be the most diverse group of species, exhibiting numerous forms of endosymbiotic associations. Molecular techniques have provided significant indicators for insect-microbe interactions. The present study aimed to register one of the true bugs of pentatomomorpha and clarify its taxonomic position through phylogenetic analysis of the partial 16S rRNA gene region. A maximum likelihood analysis retrieved a generally well-supported phylogeny based on Tamura 3-parameter model. Based on the partial mitochondrial 16S rRNA gene sequences, a phylogenetic study of suborder Heteroptera relationships within Hemipteras' order was constructed. Sequences of 221 bases of the 3' end of the gene from 28 species within 16 families were analyzed. This analysis and bootstrap confidence revealed two major clades comprising four suborders within Hemiptera, with a close relationship between Heteroptera + (Sternorrhyncha + (Auchenorrhycha + Coleorrhyncha)). Infraorder Pentatomomorpha is forming a sister group with a substantial bootstrap value to Cimicomorpha. Pyrrhocoroidea forms a sister relationship with Lygaeoidea + Coreoidea. There is a close relationship between Largidae and Pyrrhocoridae within Pyrrhocoroidea. The results show that the present species is firmly embedded in the genus Arhaphe with 94.35% sequence resemblance to its congeners. Besides, the recovered hemipteran species considered a potential model group for studying different symbionts. We propose both phylogenetic and ecological evolutionary developmental biology viewpoints for a more synthetic understanding of insect populations' molecular evolution.
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Affiliation(s)
- Rewaida Abdel-Gaber
- Zoology Department, College of Science, King Saud University, Riyadh, Saudi Arabia.,Zoology Department, Faculty of Science, Cairo University, Cairo, Egypt
| | - Reem Alajmi
- Zoology Department, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Rania Haddadi
- Zoology Department, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Saeed El-Ashram
- College of Life Science and Engineering, Foshan University, Foshan, Guangdong Province, China.,Faculty of Science, Kafr El-Sheikh University, Kafr El-Sheikh, Egypt
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24
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Miyazawa H, Osigus HJ, Rolfes S, Kamm K, Schierwater B, Nakano H. Mitochondrial Genome Evolution of Placozoans: Gene Rearrangements and Repeat Expansions. Genome Biol Evol 2020; 13:5919586. [PMID: 33031489 PMCID: PMC7813641 DOI: 10.1093/gbe/evaa213] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/30/2020] [Indexed: 12/16/2022] Open
Abstract
Placozoans, nonbilaterian animals with the simplest known metazoan bauplan, are currently classified into 20 haplotypes belonging to three genera, Polyplacotoma, Trichoplax, and Hoilungia. The latter two comprise two and five clades, respectively. In Trichoplax and Hoilungia, previous studies on six haplotypes belonging to four different clades have shown that their mtDNAs are circular chromosomes of 32–43 kb in size, which encode 12 protein-coding genes, 24 tRNAs, and two rRNAs. These mitochondrial genomes (mitogenomes) also show unique features rarely seen in other metazoans, including open reading frames (ORFs) of unknown function, and group I and II introns. Here, we report seven new mitogenomes, covering the five previously described haplotypes H2, H17, H19, H9, and H11, as well as two new haplotypes, H23 (clade III) and H24 (clade VII). The overall gene content is shared between all placozoan mitochondrial genomes, but genome sizes, gene orders, and several exon–intron boundaries vary among clades. Phylogenomic analyses strongly support a tree topology different from previous 16S rRNA analyses, with clade VI as the sister group to all other Hoilungia clades. We found small inverted repeats in all 13 mitochondrial genomes of the Trichoplax and Hoilungia genera and evaluated their distribution patterns among haplotypes. Because Polyplacotoma mediterranea (H0), the sister to the remaining haplotypes, has a small mitochondrial genome with few small inverted repeats and ORFs, we hypothesized that the proliferation of inverted repeats and ORFs substantially contributed to the observed increase in the size and GC content of the Trichoplax and Hoilungia mitochondrial genomes.
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Affiliation(s)
- Hideyuki Miyazawa
- Center for Genome Informatics, Joint Support-Center for Data Science Research, Research Organization of Information and Systems, Mishima, Shizuoka, Japan.,Shimoda Marine Research Center, University of Tsukuba, Shimoda, Shizuoka, Japan
| | - Hans-Jürgen Osigus
- Division of Molecular Evolution, Institute of Animal Ecology, University of Veterinary Medicine Hannover, Foundation, Germany
| | - Sarah Rolfes
- Division of Molecular Evolution, Institute of Animal Ecology, University of Veterinary Medicine Hannover, Foundation, Germany
| | - Kai Kamm
- Division of Molecular Evolution, Institute of Animal Ecology, University of Veterinary Medicine Hannover, Foundation, Germany
| | - Bernd Schierwater
- Division of Molecular Evolution, Institute of Animal Ecology, University of Veterinary Medicine Hannover, Foundation, Germany
| | - Hiroaki Nakano
- Shimoda Marine Research Center, University of Tsukuba, Shimoda, Shizuoka, Japan
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25
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Abstract
Evolutionary transitions in individuality (hereafter, ETIs), such as the transition to multi-cellularity and the transition to social colonies, have been at the centre of evolutionary research, but only few attempts were made to systematically operationalize this concept. Here, we devise a set of four indicators intended to assess the change in complexity during ETIs: system size, inseparability, reproductive specialization and non-reproductive specialization. We then conduct a quantitative comparison across multiple taxa and ETIs. Our analysis reveals that inseparability has a crucial role in the process; it seems irreversible and may mark the point where a group of individuals becomes a new individual at a higher hierarchical level. Interestingly, we find that disparate groups demonstrate a similar pattern of progression along ETIs.
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Affiliation(s)
- Yohay Carmel
- Faculty of Civil and Environmental Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Ayelet Shavit
- Department of Environmental Sciences, Tel Hai College, Tel-Hai 12208, Israel
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26
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Schultz DT, Eizenga JM, Corbett-Detig RB, Francis WR, Christianson LM, Haddock SH. Conserved novel ORFs in the mitochondrial genome of the ctenophore Beroe forskalii. PeerJ 2020; 8:e8356. [PMID: 32025367 PMCID: PMC6991124 DOI: 10.7717/peerj.8356] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 12/04/2019] [Indexed: 11/20/2022] Open
Abstract
To date, five ctenophore species' mitochondrial genomes have been sequenced, and each contains open reading frames (ORFs) that if translated have no identifiable orthologs. ORFs with no identifiable orthologs are called unidentified reading frames (URFs). If truly protein-coding, ctenophore mitochondrial URFs represent a little understood path in early-diverging metazoan mitochondrial evolution and metabolism. We sequenced and annotated the mitochondrial genomes of three individuals of the beroid ctenophore Beroe forskalii and found that in addition to sharing the same canonical mitochondrial genes as other ctenophores, the B. forskalii mitochondrial genome contains two URFs. These URFs are conserved among the three individuals but not found in other sequenced species. We developed computational tools called pauvre and cuttlery to determine the likelihood that URFs are protein coding. There is evidence that the two URFs are under negative selection, and a novel Bayesian hypothesis test of trinucleotide frequency shows that the URFs are more similar to known coding genes than noncoding intergenic sequence. Protein structure and function prediction of all ctenophore URFs suggests that they all code for transmembrane transport proteins. These findings, along with the presence of URFs in other sequenced ctenophore mitochondrial genomes, suggest that ctenophores may have uncharacterized transmembrane proteins present in their mitochondria.
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Affiliation(s)
- Darrin T. Schultz
- Department of Biomolecular Engineering and Bioinformatics, University of California Santa Cruz, Santa Cruz, CA, USA
- Monterey Bay Aquarium Research Institute, Moss Landing, CA, USA
| | - Jordan M. Eizenga
- Department of Biomolecular Engineering and Bioinformatics, University of California Santa Cruz, Santa Cruz, CA, USA
| | - Russell B. Corbett-Detig
- Department of Biomolecular Engineering and Bioinformatics, University of California Santa Cruz, Santa Cruz, CA, USA
| | - Warren R. Francis
- Department of Biology, University of Southern Denmark, Odense, Denmark
| | | | - Steven H.D. Haddock
- Monterey Bay Aquarium Research Institute, Moss Landing, CA, USA
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, CA, USA
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27
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Rosani U, Domeneghetti S, Gerdol M, Pallavicini A, Venier P. Expansion and loss events characterized the occurrence of MIF-like genes in bivalves. FISH & SHELLFISH IMMUNOLOGY 2019; 93:39-49. [PMID: 31306763 DOI: 10.1016/j.fsi.2019.07.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 06/14/2019] [Accepted: 07/10/2019] [Indexed: 06/10/2023]
Abstract
Macrophage migration inhibitory factor (MIF) dynamically connects innate and adaptive immune systems in vertebrate animals, allowing highly orchestrated systemic responses to various insults. The occurrence of MIF-like genes in non-vertebrate organisms suggests its origin from an ancestral metazoan gene, whose function is still a matter of debate. In the present work, by analyzing available genomic and transcriptomic data from bivalve mollusks, we identified 137 MIF-like sequences, which were classified into three types, based on phylogeny and conservation of key residues: MIF, D-DT, and the lineage-specific type MDL. Comparative genomics revealed syntenic conservation of homologous genes at the family level, the loss of D-DT in the Ostreidae family as well as the expansion of MIF-like genes in the Mytilidae family, possibly underpinning the neofunctionalization of duplicated gene copies. In M. galloprovincialis, MIF and one D-DT were mostly expressed in haemocytes and mantle rim of untreated animals, while D-DT paralogs often showed very limited expression, suggesting an accessory role or their persistence as relict genes.
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Affiliation(s)
- Umberto Rosani
- Department of Biology, University of Padova, via U. Bassi 58/b, 35121, Padova, Italy; AWI Alfred Wegener Institute, Coastal Ecology, Hafenstraße 43, 25992, List auf Sylt, Germany.
| | - Stefania Domeneghetti
- Department of Biology, University of Padova, via U. Bassi 58/b, 35121, Padova, Italy
| | - Marco Gerdol
- Department of Life Sciences, University of Trieste, via L. Giorgeri 5, 34127, Trieste, Italy
| | - Alberto Pallavicini
- Department of Life Sciences, University of Trieste, via L. Giorgeri 5, 34127, Trieste, Italy
| | - Paola Venier
- Department of Biology, University of Padova, via U. Bassi 58/b, 35121, Padova, Italy.
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28
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DuBuc TQ, Ryan JF, Martindale MQ. "Dorsal-Ventral" Genes Are Part of an Ancient Axial Patterning System: Evidence from Trichoplax adhaerens (Placozoa). Mol Biol Evol 2019; 36:966-973. [PMID: 30726986 PMCID: PMC6501881 DOI: 10.1093/molbev/msz025] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Placozoa are a morphologically simplistic group of marine animals found globally in tropical and subtropical environments. They consist of two named species, Trichoplax adhaerens and more recently Hoilungia hongkongensis, both with roughly six morphologically distinct cell types. With a sequenced genome, a limited number of cell types, and a simple flattened morphology, Trichoplax is an ideal model organism from which to explore the biology of an animal with a cellular complexity analagous to that of the earliest animals. Using a new approach for identification of gene expression patterns, this research looks at the relationship of Chordin/TgfΒ signaling and the axial patterning system of Placozoa. Our results suggest that placozoans have an oral-aboral axis similar to cnidarians and that the parahoxozoan ancestor (common ancestor of Placozoa and Cnidaria) was likely radially symmetric.
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Affiliation(s)
- Timothy Q DuBuc
- Whitney Lab for Marine Bioscience and the Department of Biology, University of Florida, St. Augustine, FL
- Kewalo Marine Laboratory and the Department of Biology, University of Hawaii, Manoa, Honolulu, HI
- Centre for Chromosome Biology, Bioscience Building, National University of Ireland Galway, Galway, Ireland
| | - Joseph F Ryan
- Whitney Lab for Marine Bioscience and the Department of Biology, University of Florida, St. Augustine, FL
| | - Mark Q Martindale
- Whitney Lab for Marine Bioscience and the Department of Biology, University of Florida, St. Augustine, FL
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29
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Features of a novel protein, rusticalin, from the ascidian Styela rustica reveal ancestral horizontal gene transfer event. Mob DNA 2019; 10:4. [PMID: 30675192 PMCID: PMC6339383 DOI: 10.1186/s13100-019-0146-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 01/02/2019] [Indexed: 12/18/2022] Open
Abstract
Background The transfer of genetic material from non-parent organisms is called horizontal gene transfer (HGT). One of the most conclusive cases of HGT in metazoans was previously described for the cellulose synthase gene in ascidians. Results In this study we identified a new protein, rusticalin, from the ascidian Styela rustica and presented evidence for its likely origin by HGT. Discernible homologues of rusticalin were found in placozoans, coral, and basal Chordates. Rusticalin was predicted to consist of two distinct regions, an N-terminal domain and a C-terminal domain. The N-terminal domain comprises two cysteine-rich repeats and shows remote similarity to the tick carboxypeptidase inhibitor. The C-terminal domain shares significant sequence similarity with bacterial MD peptidases and bacteriophage A500 L-alanyl-D-glutamate peptidase. A possible transfer of the C-terminal domain by bacteriophage was confirmed by an analysis of noncoding sequences of C. intestinalis rusticalin-like gene, which was found to contain a sequence similar to the bacteriophage A500 recombination site. Moreover, a sequence similar to the bacteriophage recombination site was found to be adjacent to the cellulose synthase catalytic subunit gene in the genome of Streptomices sp., the donor of ascidian cellulose synthase. Conclusions The C-terminal domain of rusticalin and rusticalin-like proteins is likely to be horizontally transferred by the bacteriophage A500. A common mechanism involving bacteriophage mediated gene transfer can be proposed for at least two HGT events in ascidians.
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30
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Kamm K, Osigus HJ, Stadler PF, DeSalle R, Schierwater B. Trichoplax genomes reveal profound admixture and suggest stable wild populations without bisexual reproduction. Sci Rep 2018; 8:11168. [PMID: 30042472 PMCID: PMC6057997 DOI: 10.1038/s41598-018-29400-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 07/09/2018] [Indexed: 12/24/2022] Open
Abstract
The phylum Placozoa officially consists of only a single described species, Trichoplax adhaerens, although several lineages can be separated by molecular markers, geographical distributions and environmental demands. The placozoan 16S haplotype H2 (Trichoplax sp. H2) is the most robust and cosmopolitan lineage of placozoans found to date. In this study, its genome was found to be distinct but highly related to the Trichoplax adhaerens reference genome, for remarkably unique reasons. The pattern of variation and allele distribution between the two lineages suggests that both originate from a single interbreeding event in the wild, dating back at least several decades ago, and both seem not to have engaged in sexual reproduction since. We conclude that populations of certain placozoan haplotypes remain stable for long periods without bisexual reproduction. Furthermore, allelic variation within and between the two Trichoplax lineages indicates that successful bisexual reproduction between related placozoan lineages might serve to either counter accumulated negative somatic mutations or to cope with changing environmental conditions. On the other hand, enrichment of neutral or beneficial somatic mutations by vegetative reproduction, combined with rare sexual reproduction, could instantaneously boost genetic variation, generating novel ecotypes and eventually species.
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Affiliation(s)
- Kai Kamm
- University of Veterinary Medicine Hannover, Foundation, ITZ Ecology and Evolution, Bünteweg 17d, D-30559, Hannover, Germany.
| | - Hans-Jürgen Osigus
- University of Veterinary Medicine Hannover, Foundation, ITZ Ecology and Evolution, Bünteweg 17d, D-30559, Hannover, Germany
| | - Peter F Stadler
- Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, University of Leipzig, Härtelstraße 16-18, D-04107, Leipzig, Germany
| | - Rob DeSalle
- Sackler Institute for Comparative Genomics and Division of Invertebrate Zoology, American Museum of Natural History, New York, New York, USA
| | - Bernd Schierwater
- University of Veterinary Medicine Hannover, Foundation, ITZ Ecology and Evolution, Bünteweg 17d, D-30559, Hannover, Germany. .,Sackler Institute for Comparative Genomics and Division of Invertebrate Zoology, American Museum of Natural History, New York, New York, USA. .,Yale University, Molecular, Cellular and Developmental Biology, New Haven, CT, 06520, USA.
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31
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Haen Whitmer KM. Model Systems for Exploring the Evolutionary Origins of the Nervous System. Results Probl Cell Differ 2018; 65:185-196. [PMID: 30083921 DOI: 10.1007/978-3-319-92486-1_10] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
The development of nervous systems can be seen as one of the key transitions in animal evolution, allowing the efficient integration of sensory input and motor output and the expedient transmission of impulses over relatively long distances inside an organism. With the increased availability of genome sequences for animals at the base of the metazoan phylogenetic tree, two alternative hypotheses have been proposed regarding nervous system evolutionary origins, ultimately prompting a debate whether an enormously complicated system like the nervous system could have evolved more than once. This review summarizes what is currently known about nervous system origins, concentrating on the evolution of synapse components, with respect to phylogenetic knowledge of early diverging animal groups, comprising members of the Porifera, Ctenophora, Placozoa, and Cnidaria.
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Affiliation(s)
- Karri M Haen Whitmer
- Department of Genetics, Development & Cell Biology, Iowa State University, Ames, IA, USA.
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32
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Szafranski P. Intercompartmental Piecewise Gene Transfer. Genes (Basel) 2017; 8:genes8100260. [PMID: 28984842 PMCID: PMC5664110 DOI: 10.3390/genes8100260] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 09/25/2017] [Accepted: 09/28/2017] [Indexed: 11/16/2022] Open
Abstract
Gene relocation from the residual genomes of organelles to the nuclear genome still continues, although as a scaled down evolutionary phenomenon, limited in occurrence mostly to protists (sensu lato) and land plants. During this process, the structural integrity of transferred genes is usually preserved. However, the relocation of mitochondrial genes that code for respiratory chain and ribosomal proteins is sometimes associated with their fragmentation into two complementary genes. Herein, this review compiles cases of piecewise gene transfer from the mitochondria to the nucleus, and discusses hypothesized mechanistic links between the fission and relocation of those genes.
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Affiliation(s)
- Przemyslaw Szafranski
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
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33
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Abstract
The evolutionary origin of synapses and neurons is an enigmatic subject that inspires much debate. Non-bilaterian metazoans, both with and without neurons and their closest relatives already contain many components of the molecular toolkits for synapse functions. The origin of these components and their assembly into ancient synaptic signaling machineries are particularly important in light of recent findings on the phylogeny of non-bilaterian metazoans. The evolution of synapses and neurons are often discussed only from a metazoan perspective leaving a considerable gap in our understanding. By taking an integrative approach we highlight the need to consider different, but extremely relevant phyla and to include the closest unicellular relatives of metazoans, the ichthyosporeans, filastereans and choanoflagellates, to fully understand the evolutionary origin of synapses and neurons. This approach allows for a detailed understanding of when and how the first pre- and postsynaptic signaling machineries evolved.
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Affiliation(s)
- Pawel Burkhardt
- Marine Biological Association of the United Kingdom, The Laboratory, Citadel Hill, Plymouth, United Kingdom
| | - Simon G Sprecher
- Institute of Cell and Developmental Biology, Department of Biology, University of Fribourg, Fribourg, Switzerland
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34
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Kück P, Wilkinson M, Groß C, Foster PG, Wägele JW. Can quartet analyses combining maximum likelihood estimation and Hennigian logic overcome long branch attraction in phylogenomic sequence data? PLoS One 2017; 12:e0183393. [PMID: 28841676 PMCID: PMC5571918 DOI: 10.1371/journal.pone.0183393] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 08/03/2017] [Indexed: 12/28/2022] Open
Abstract
Systematic biases such as long branch attraction can mislead commonly relied upon model-based (i.e. maximum likelihood and Bayesian) phylogenetic methods when, as is usually the case with empirical data, there is model misspecification. We present PhyQuart, a new method for evaluating the three possible binary trees for any quartet of taxa. PhyQuart was developed through a process of reciprocal illumination between a priori considerations and the results of extensive simulations. It is based on identification of site-patterns that can be considered to support a particular quartet tree taking into account the Hennigian distinction between apomorphic and plesiomorphic similarity, and employing corrections to the raw observed frequencies of site-patterns that exploit expectations from maximum likelihood estimation. We demonstrate through extensive simulation experiments that, whereas maximum likeilihood estimation performs well in many cases, it can be outperformed by PhyQuart in cases where it fails due to extreme branch length asymmetries producing long-branch attraction artefacts where there is only very minor model misspecification.
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Affiliation(s)
- Patrick Kück
- Zoologisches Forschungsmuseum Alexander Koenig, Bonn, 53113, Germany
- The Natural History Museum, London, SW7 5BD, United Kingdom
| | - Mark Wilkinson
- The Natural History Museum, London, SW7 5BD, United Kingdom
| | - Christian Groß
- The Natural History Museum, London, SW7 5BD, United Kingdom
- Delft University of Technology, Delft, 2628 CD, The Netherlands
| | | | - Johann W. Wägele
- Zoologisches Forschungsmuseum Alexander Koenig, Bonn, 53113, Germany
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35
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Isom GL, Davies NJ, Chong ZS, Bryant JA, Jamshad M, Sharif M, Cunningham AF, Knowles TJ, Chng SS, Cole JA, Henderson IR. MCE domain proteins: conserved inner membrane lipid-binding proteins required for outer membrane homeostasis. Sci Rep 2017; 7:8608. [PMID: 28819315 PMCID: PMC5561183 DOI: 10.1038/s41598-017-09111-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 07/20/2017] [Indexed: 01/12/2023] Open
Abstract
Bacterial proteins with MCE domains were first described as being important for Mammalian Cell Entry. More recent evidence suggests they are components of lipid ABC transporters. In Escherichia coli, the single-domain protein MlaD is known to be part of an inner membrane transporter that is important for maintenance of outer membrane lipid asymmetry. Here we describe two multi MCE domain-containing proteins in Escherichia coli, PqiB and YebT, the latter of which is an orthologue of MAM-7 that was previously reported to be an outer membrane protein. We show that all three MCE domain-containing proteins localise to the inner membrane. Bioinformatic analyses revealed that MCE domains are widely distributed across bacterial phyla but multi MCE domain-containing proteins evolved in Proteobacteria from single-domain proteins. Mutants defective in mlaD, pqiAB and yebST were shown to have distinct but partially overlapping phenotypes, but the primary functions of PqiB and YebT differ from MlaD. Complementing our previous findings that all three proteins bind phospholipids, results presented here indicate that multi-domain proteins evolved in Proteobacteria for specific functions in maintaining cell envelope homeostasis.
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Affiliation(s)
- Georgia L Isom
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom
| | - Nathaniel J Davies
- Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, United Kingdom
| | - Zhi-Soon Chong
- Department of Chemistry, National University of Singapore, Singapore, Singapore
| | - Jack A Bryant
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom
| | - Mohammed Jamshad
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom
| | - Maria Sharif
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom
| | - Adam F Cunningham
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom
| | - Timothy J Knowles
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom
| | - Shu-Sin Chng
- Department of Chemistry, National University of Singapore, Singapore, Singapore
| | - Jeffrey A Cole
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom
| | - Ian R Henderson
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom.
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36
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Osigus HJ, Eitel M, Schierwater B. Deep RNA sequencing reveals the smallest known mitochondrial micro exon in animals: The placozoan cox1 single base pair exon. PLoS One 2017; 12:e0177959. [PMID: 28542197 PMCID: PMC5436844 DOI: 10.1371/journal.pone.0177959] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 05/05/2017] [Indexed: 11/18/2022] Open
Abstract
The phylum Placozoa holds a key position for our understanding of the evolution of mitochondrial genomes in Metazoa. Placozoans possess large mitochondrial genomes which harbor several remarkable characteristics such as a fragmented cox1 gene and trans-splicing cox1 introns. A previous study also suggested the existence of cox1 mRNA editing in Trichoplax adhaerens, yet the only formally described species in the phylum Placozoa. We have analyzed RNA-seq data of the undescribed sister species, Placozoa sp. H2 ("Panama" clone), with special focus on the mitochondrial mRNA. While we did not find support for a previously postulated cox1 mRNA editing mechanism, we surprisingly found two independent transcripts representing intermediate cox1 mRNA splicing stages. Both transcripts consist of partial cox1 exon as well as overlapping intron fragments. The data suggest that the cox1 gene harbors a single base pair (cytosine) micro exon. Furthermore, conserved group I intron structures flank this unique micro exon also in other placozoans. We discuss the evolutionary origin of this micro exon in the context of a self-splicing intron gain in the cox1 gene of the last common ancestor of extant placozoans.
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Affiliation(s)
- Hans-Jürgen Osigus
- ITZ, Ecology & Evolution, Stiftung Tierärztliche Hochschule Hannover, Hannover, Germany
| | - Michael Eitel
- ITZ, Ecology & Evolution, Stiftung Tierärztliche Hochschule Hannover, Hannover, Germany
| | - Bernd Schierwater
- ITZ, Ecology & Evolution, Stiftung Tierärztliche Hochschule Hannover, Hannover, Germany
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, United States of America
- Sackler Institute for Comparative Genomics and Division of Invertebrate Zoology, American Museum of Natural History, New York, New York, United States of America
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Schuster A, Lopez JV, Becking LE, Kelly M, Pomponi SA, Wörheide G, Erpenbeck D, Cárdenas P. Evolution of group I introns in Porifera: new evidence for intron mobility and implications for DNA barcoding. BMC Evol Biol 2017; 17:82. [PMID: 28320321 PMCID: PMC5360047 DOI: 10.1186/s12862-017-0928-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 02/28/2017] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Mitochondrial introns intermit coding regions of genes and feature characteristic secondary structures and splicing mechanisms. In metazoans, mitochondrial introns have only been detected in sponges, cnidarians, placozoans and one annelid species. Within demosponges, group I and group II introns are present in six families. Based on different insertion sites within the cox1 gene and secondary structures, four types of group I and two types of group II introns are known, which can harbor up to three encoding homing endonuclease genes (HEG) of the LAGLIDADG family (group I) and/or reverse transcriptase (group II). However, only little is known about sponge intron mobility, transmission, and origin due to the lack of a comprehensive dataset. We analyzed the largest dataset on sponge mitochondrial group I introns to date: 95 specimens, from 11 different sponge genera which provided novel insights into the evolution of group I introns. RESULTS For the first time group I introns were detected in four genera of the sponge family Scleritodermidae (Scleritoderma, Microscleroderma, Aciculites, Setidium). We demonstrated that group I introns in sponges aggregate in the most conserved regions of cox1. We showed that co-occurrence of two introns in cox1 is unique among metazoans, but not uncommon in sponges. However, this combination always associates an active intron with a degenerating one. Earlier hypotheses of HGT were confirmed and for the first time VGT and secondary losses of introns conclusively demonstrated. CONCLUSION This study validates the subclass Spirophorina (Tetractinellida) as an intron hotspot in sponges. Our analyses confirm that most sponge group I introns probably originated from fungi. DNA barcoding is discussed and the application of alternative primers suggested.
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Affiliation(s)
- Astrid Schuster
- Department of Earth- & Environmental Sciences, Palaeontology and Geobiology, Ludwig-Maximilians-Universität München, Richard-Wagner-Str. 10, 80333 Munich, Germany
| | - Jose V. Lopez
- Halmos College of Natural Sciences and Oceanography, Nova Southeastern University, Dania Beach, FL 33004 USA
| | - Leontine E. Becking
- Marine Animal Ecology, Wageningen University & Research Centre, P.O. Box 3700, AH, Wageningen, The Netherlands
- Naturalis Biodiversity Center, Marine Zoology Department, PO Box 9517, 2300 RA, Leiden, The Netherlands
| | - Michelle Kelly
- National Centre for Aquatic Biodiversity and Biosecurity, National Institute of Water and Atmospheric Research, P.O. Box 109–695, Newmarket, Auckland, New Zealand
| | - Shirley A. Pomponi
- Harbor Branch Oceanographic Institute-Florida Atlantic University, 5600 U.S. 1 North, Ft Pierce, FL 34946 USA
| | - Gert Wörheide
- Department of Earth- & Environmental Sciences, Palaeontology and Geobiology, Ludwig-Maximilians-Universität München, Richard-Wagner-Str. 10, 80333 Munich, Germany
- SNSB - Bavarian State Collections of Palaeontology and Geology, Richard-Wagner Str. 10, 80333 Munich, Germany
- GeoBio-CenterLMU, Ludwig-Maximilians-Universität München, Richard-Wagner Str. 10, 80333 Munich, Germany
| | - Dirk Erpenbeck
- Department of Earth- & Environmental Sciences, Palaeontology and Geobiology, Ludwig-Maximilians-Universität München, Richard-Wagner-Str. 10, 80333 Munich, Germany
- GeoBio-CenterLMU, Ludwig-Maximilians-Universität München, Richard-Wagner Str. 10, 80333 Munich, Germany
| | - Paco Cárdenas
- Department of Medicinal Chemistry, Division of Pharmacognosy, BioMedical Center, Uppsala University, Husargatan 3, 75123 Uppsala, Sweden
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Evolutionary and biogeographical implications of degraded LAGLIDADG endonuclease functionality and group I intron occurrence in stony corals (Scleractinia) and mushroom corals (Corallimorpharia). PLoS One 2017; 12:e0173734. [PMID: 28278261 PMCID: PMC5344465 DOI: 10.1371/journal.pone.0173734] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 02/24/2017] [Indexed: 11/29/2022] Open
Abstract
Group I introns and homing endonuclease genes (HEGs) are mobile genetic elements, capable of invading target sequences in intron-less genomes. LAGLIDADG HEGs are the largest family of endonucleases, playing a key role in the mobility of group I introns in a process known as ‘homing’. Group I introns and HEGs are rare in metazoans, and can be mainly found inserted in the COXI gene of some sponges and cnidarians, including stony corals (Scleractinia) and mushroom corals (Corallimorpharia). Vertical and horizontal intron transfer mechanisms have been proposed as explanations for intron occurrence in cnidarians. However, the central role of LAGLIDADG motifs in intron mobility mechanisms remains poorly understood. To resolve questions regarding the evolutionary origin and distribution of group I introns and HEGs in Scleractinia and Corallimorpharia, we examined intron/HEGs sequences within a comprehensive phylogenetic framework. Analyses of LAGLIDADG motif conservation showed a high degree of degradation in complex Scleractinia and Corallimorpharia. Moreover, the two motifs lack the respective acidic residues necessary for metal-ion binding and catalysis, potentially impairing horizontal intron mobility. In contrast, both motifs are highly conserved within robust Scleractinia, indicating a fully functional endonuclease capable of promoting horizontal intron transference. A higher rate of non-synonymous substitutions (Ka) detected in the HEGs of complex Scleractinia and Corallimorpharia suggests degradation of the HEG, whereas lower Ka rates in robust Scleractinia are consistent with a scenario of purifying selection. Molecular-clock analyses and ancestral inference of intron type indicated an earlier intron insertion in complex Scleractinia and Corallimorpharia in comparison to robust Scleractinia. These findings suggest that the lack of horizontal intron transfers in the former two groups is related to an age-dependent degradation of the endonuclease activity. Moreover, they also explain the peculiar geographical patterns of introns in stony and mushroom corals.
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Senatore A, Raiss H, Le P. Physiology and Evolution of Voltage-Gated Calcium Channels in Early Diverging Animal Phyla: Cnidaria, Placozoa, Porifera and Ctenophora. Front Physiol 2016; 7:481. [PMID: 27867359 PMCID: PMC5095125 DOI: 10.3389/fphys.2016.00481] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Accepted: 10/07/2016] [Indexed: 12/18/2022] Open
Abstract
Voltage-gated calcium (Cav) channels serve dual roles in the cell, where they can both depolarize the membrane potential for electrical excitability, and activate transient cytoplasmic Ca2+ signals. In animals, Cav channels play crucial roles including driving muscle contraction (excitation-contraction coupling), gene expression (excitation-transcription coupling), pre-synaptic and neuroendocrine exocytosis (excitation-secretion coupling), regulation of flagellar/ciliary beating, and regulation of cellular excitability, either directly or through modulation of other Ca2+-sensitive ion channels. In recent years, genome sequencing has provided significant insights into the molecular evolution of Cav channels. Furthermore, expanded gene datasets have permitted improved inference of the species phylogeny at the base of Metazoa, providing clearer insights into the evolution of complex animal traits which involve Cav channels, including the nervous system. For the various types of metazoan Cav channels, key properties that determine their cellular contribution include: Ion selectivity, pore gating, and, importantly, cytoplasmic protein-protein interactions that direct sub-cellular localization and functional complexing. It is unclear when these defining features, many of which are essential for nervous system function, evolved. In this review, we highlight some experimental observations that implicate Cav channels in the physiology and behavior of the most early-diverging animals from the phyla Cnidaria, Placozoa, Porifera, and Ctenophora. Given our limited understanding of the molecular biology of Cav channels in these basal animal lineages, we infer insights from better-studied vertebrate and invertebrate animals. We also highlight some apparently conserved cellular functions of Cav channels, which might have emerged very early on during metazoan evolution, or perhaps predated it.
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Affiliation(s)
- Adriano Senatore
- Department of Biology, University of Toronto Mississauga Mississauga, ON, Canada
| | - Hamad Raiss
- Department of Biology, University of Toronto Mississauga Mississauga, ON, Canada
| | - Phuong Le
- Department of Biology, University of Toronto Mississauga Mississauga, ON, Canada
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Lavrov DV, Pett W. Animal Mitochondrial DNA as We Do Not Know It: mt-Genome Organization and Evolution in Nonbilaterian Lineages. Genome Biol Evol 2016; 8:2896-2913. [PMID: 27557826 PMCID: PMC5633667 DOI: 10.1093/gbe/evw195] [Citation(s) in RCA: 130] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/06/2016] [Indexed: 12/11/2022] Open
Abstract
Animal mitochondrial DNA (mtDNA) is commonly described as a small, circular molecule that is conserved in size, gene content, and organization. Data collected in the last decade have challenged this view by revealing considerable diversity in animal mitochondrial genome organization. Much of this diversity has been found in nonbilaterian animals (phyla Cnidaria, Ctenophora, Placozoa, and Porifera), which, from a phylogenetic perspective, form the main branches of the animal tree along with Bilateria. Within these groups, mt-genomes are characterized by varying numbers of both linear and circular chromosomes, extra genes (e.g. atp9, polB, tatC), large variation in the number of encoded mitochondrial transfer RNAs (tRNAs) (0-25), at least seven different genetic codes, presence/absence of introns, tRNA and mRNA editing, fragmented ribosomal RNA genes, translational frameshifting, highly variable substitution rates, and a large range of genome sizes. This newly discovered diversity allows a better understanding of the evolutionary plasticity and conservation of animal mtDNA and provides insights into the molecular and evolutionary mechanisms shaping mitochondrial genomes.
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Affiliation(s)
- Dennis V Lavrov
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University
| | - Walker Pett
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University Laboratoire de Biométrie et Biologie Évolutive, Université Lyon 1, Villeurbanne, France
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41
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Devi KM, Shantibala T, Debaraj H. The first complete mitochondrial genome of a Belostomatidae species, Lethocerus indicus, the giant water bug: An important edible insect. Gene 2016; 591:108-118. [PMID: 27390089 DOI: 10.1016/j.gene.2016.07.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 07/01/2016] [Accepted: 07/03/2016] [Indexed: 11/30/2022]
Abstract
Lethocerus indicus of the family Belostomatidae is one of the most preferred and delicious edible insects in different parts of South-East Asia including North-East, India. The mitogenome of L. indicus represents the first complete mitogenome sequence of a Belostomatidae species in Heteroptera order. The mitogenome of L. indicus is 16,251bp and contains 37 genes including 13 protein coding genes (PCGs), 22 tRNA genes, two rRNA genes, and a large non-coding region. The genome has a typical gene order which is identical to other Heteroptera species. All tRNAs exhibit the classic cloverleaf secondary structure except tRNASer (AGN). All the PCGs employ a complete translation termination codon either TAA or TAG except COII. The nucleotide composition showed heavy biased toward AT accounting to 70.9% of total mitogenome. The overall A+T content of L. indicus mitogenome was comparatively lower than some other Heteropteran bugs mitogenomes. The control region is divided into seven different parts which includes the putative stem loop, repeats, tandem repeats, GC and AT rich regions. The phylogenetic relationship based on maximum-likelihood method using all protein coding genes was congruent with the traditional morphological classification that Belostomatidae is closely related to Nepidae. The complete mitogenome sequence of L. indicus provides fundamental data useful in conservation genetics and aquaculture diversification.
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Affiliation(s)
- Kshetrimayum Miranda Devi
- Animal Bioresources Division, Institute of Bioresources and Sustainable Development (IBSD), Takyelpat Institutional Area, Imphal- 795001, Manipur, India
| | - Tourangbam Shantibala
- Animal Bioresources Division, Institute of Bioresources and Sustainable Development (IBSD), Takyelpat Institutional Area, Imphal- 795001, Manipur, India.
| | - Hajarimayum Debaraj
- Animal Bioresources Division, Institute of Bioresources and Sustainable Development (IBSD), Takyelpat Institutional Area, Imphal- 795001, Manipur, India
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42
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Kelly M, Cárdenas P. An unprecedented new genus and family of Tetractinellida (Porifera, Demospongiae) from New Zealand's Colville Ridge, with a new type of mitochondrial group I intron. Zool J Linn Soc 2016. [DOI: 10.1111/zoj.12365] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Michelle Kelly
- Coasts and Oceans National Centre; National Institute of Water & Atmospheric Research Ltd; Private Bag 99940 Newmarket Auckland New Zealand
| | - Paco Cárdenas
- Department of Medicinal Chemistry; Division of Pharmacognosy; BioMedical Centre; Husargatan 3; Uppsala University; 751 23 Uppsala Sweden
- Department of Systematic Biology; Evolutionary Biology Centre; Uppsala University; Norbyvägen 18D 752 36 Uppsala Sweden
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43
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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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O'Malley MA. Histories of molecules: Reconciling the past. STUDIES IN HISTORY AND PHILOSOPHY OF SCIENCE 2016; 55:69-83. [PMID: 26774071 DOI: 10.1016/j.shpsa.2015.09.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 09/07/2015] [Accepted: 09/08/2015] [Indexed: 06/05/2023]
Abstract
Molecular data and methods have become centrally important to evolutionary analysis, largely because they have enabled global phylogenetic reconstructions of the relationships between organisms in the tree of life. Often, however, molecular stories conflict dramatically with morphology-based histories of lineages. The evolutionary origin of animal groups provides one such case. In other instances, different molecular analyses have so far proved irreconcilable. The ancient and major divergence of eukaryotes from prokaryotic ancestors is an example of this sort of problem. Efforts to overcome these conflicts highlight the role models play in phylogenetic reconstruction. One crucial model is the molecular clock; another is that of 'simple-to-complex' modification. I will examine animal and eukaryote evolution against a backdrop of increasing methodological sophistication in molecular phylogeny, and conclude with some reflections on the nature of historical science in the molecular era of phylogeny.
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45
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Moroz LL, Kohn AB. Independent origins of neurons and synapses: insights from ctenophores. Philos Trans R Soc Lond B Biol Sci 2016; 371:20150041. [PMID: 26598724 PMCID: PMC4685580 DOI: 10.1098/rstb.2015.0041] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/18/2015] [Indexed: 12/29/2022] Open
Abstract
There is more than one way to develop neuronal complexity, and animals frequently use different molecular toolkits to achieve similar functional outcomes. Genomics and metabolomics data from basal metazoans suggest that neural signalling evolved independently in ctenophores and cnidarians/bilaterians. This polygenesis hypothesis explains the lack of pan-neuronal and pan-synaptic genes across metazoans, including remarkable examples of lineage-specific evolution of neurogenic and signalling molecules as well as synaptic components. Sponges and placozoans are two lineages without neural and muscular systems. The possibility of secondary loss of neurons and synapses in the Porifera/Placozoa clades is a highly unlikely and less parsimonious scenario. We conclude that acetylcholine, serotonin, histamine, dopamine, octopamine and gamma-aminobutyric acid (GABA) were recruited as transmitters in the neural systems in cnidarian and bilaterian lineages. By contrast, ctenophores independently evolved numerous secretory peptides, indicating extensive adaptations within the clade and suggesting that early neural systems might be peptidergic. Comparative analysis of glutamate signalling also shows numerous lineage-specific innovations, implying the extensive use of this ubiquitous metabolite and intercellular messenger over the course of convergent and parallel evolution of mechanisms of intercellular communication. Therefore: (i) we view a neuron as a functional character but not a genetic character, and (ii) any given neural system cannot be considered as a single character because it is composed of different cell lineages with distinct genealogies, origins and evolutionary histories. Thus, when reconstructing the evolution of nervous systems, we ought to start with the identification of particular cell lineages by establishing distant neural homologies or examples of convergent evolution. In a corollary of the hypothesis of the independent origins of neurons, our analyses suggest that both electrical and chemical synapses evolved more than once.
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Affiliation(s)
- Leonid L Moroz
- The Whitney Laboratory for Marine Bioscience, 9505 Ocean Shore Boulevard, St Augustine, FL 32080, USA Department of Neuroscience and McKnight Brain Institute, University of Florida, Gainesville, FL 32611, USA
| | - Andrea B Kohn
- The Whitney Laboratory for Marine Bioscience, 9505 Ocean Shore Boulevard, St Augustine, FL 32080, USA
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Huchon D, Szitenberg A, Shefer S, Ilan M, Feldstein T. Mitochondrial group I and group II introns in the sponge orders Agelasida and Axinellida. BMC Evol Biol 2015; 15:278. [PMID: 26653218 PMCID: PMC4676843 DOI: 10.1186/s12862-015-0556-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2015] [Accepted: 12/03/2015] [Indexed: 11/21/2022] Open
Abstract
Background Self-splicing introns are present in the mitochondria of members of most eukaryotic lineages. They are divided into Group I and Group II introns, according to their secondary structure and splicing mechanism. Being rare in animals, self-splicing introns were only described in a few sponges, cnidarians, placozoans and one annelid species. In sponges, three types of mitochondrial Group I introns were previously described in two demosponge families (Tetillidae, and Aplysinellidae) and in the homoscleromorph family Plakinidae. These three introns differ in their insertion site, secondary structure and in the sequence of the LAGLIDADG gene they encode. Notably, no group II introns have been previously described in sponges. Results We report here the presence of mitochondrial introns in the cytochrome oxidase subunit 1 (COI) gene of three additional sponge species from three different families: Agelas oroides (Agelasidae, Agelasida), Cymbaxinellapverrucosa (Hymerhabdiidae, Agelasida) and Axinella polypoides (Axinellidae, Axinellida). We show, for the first time, that sponges can also harbour Group II introns in their COI gene, whose presence in animals’ mitochondria has so far been described in only two phyla, Placozoa and Annelida. Surprisingly, two different Group II introns were discovered in the COI gene of C. verrucosa. Phylogenetic analysis indicates that the Group II introns present in C. verrucosa are related to red algae (Rhodophyta) introns. Conclusions The differences found among intron secondary structures and the phylogenetic inferences support the hypothesis that the introns originated from independent horizontal gene transfer events. Our results thus suggest that self-splicing introns are more diverse in the mitochondrial genome of sponges than previously anticipated. Electronic supplementary material The online version of this article (doi:10.1186/s12862-015-0556-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Dorothée Huchon
- Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel. .,The Steinhardt Museum of Natural History, Israel National Center for Biodiversity Studies, Tel Aviv University, Tel Aviv, 6997801, Israel.
| | - Amir Szitenberg
- Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel. .,Current address: School of Biological, Biomedical and Environmental Sciences, University of Hull, Hull, HU6 7RX, UK.
| | - Sigal Shefer
- Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel. .,The Steinhardt Museum of Natural History, Israel National Center for Biodiversity Studies, Tel Aviv University, Tel Aviv, 6997801, Israel.
| | - Micha Ilan
- Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel.
| | - Tamar Feldstein
- Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel. .,The Steinhardt Museum of Natural History, Israel National Center for Biodiversity Studies, Tel Aviv University, Tel Aviv, 6997801, Israel.
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Hale R, Strutt D. Conservation of Planar Polarity Pathway Function Across the Animal Kingdom. Annu Rev Genet 2015; 49:529-51. [DOI: 10.1146/annurev-genet-112414-055224] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Rosalind Hale
- Bateson Centre,
- Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield S10 2TN, United Kingdom;
| | - David Strutt
- Bateson Centre,
- Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield S10 2TN, United Kingdom;
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48
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Richter S, Schwarz F, Hering L, Böggemann M, Bleidorn C. The Utility of Genome Skimming for Phylogenomic Analyses as Demonstrated for Glycerid Relationships (Annelida, Glyceridae). Genome Biol Evol 2015; 7:3443-62. [PMID: 26590213 PMCID: PMC4700955 DOI: 10.1093/gbe/evv224] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Glyceridae (Annelida) are a group of venomous annelids distributed worldwide from intertidal to abyssal depths. To trace the evolutionary history and complexity of glycerid venom cocktails, a solid backbone phylogeny of this group is essential. We therefore aimed to reconstruct the phylogenetic relationships of these annelids using Illumina sequencing technology. We constructed whole-genome shotgun libraries for 19 glycerid specimens and 1 outgroup species (Glycinde armigera). The chosen target genes comprise 13 mitochondrial proteins, 2 ribosomal mitochondrial genes, and 4 nuclear loci (18SrRNA, 28SrRNA, ITS1, and ITS2). Based on partitioned maximum likelihood as well as Bayesian analyses of the resulting supermatrix, we were finally able to resolve a robust glycerid phylogeny and identified three clades comprising the majority of taxa. Furthermore, we detected group II introns inside the cox1 gene of two analyzed glycerid specimens, with two different insertions in one of these species. Moreover, we generated reduced data sets comprising 10 million, 4 million, and 1 million reads from the original data sets to test the influence of the sequencing depth on assembling complete mitochondrial genomes from low coverage genome data. We estimated the coverage of mitochondrial genome sequences in each data set size by mapping the filtered Illumina reads against the respective mitochondrial contigs. By comparing the contig coverage calculated in all data set sizes, we got a hint for the scalability of our genome skimming approach. This allows estimating more precisely the number of reads that are at least necessary to reconstruct complete mitochondrial genomes in Glyceridae and probably non-model organisms in general.
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Affiliation(s)
- Sandy Richter
- Molecular Evolution and Animal Systematics, Institute of Biology, University of Leipzig, Germany
| | - Francine Schwarz
- Molecular Evolution and Animal Systematics, Institute of Biology, University of Leipzig, Germany
| | - Lars Hering
- Animal Evolution & Development, Institute of Biology, University of Leipzig, Germany Department of Zoology, Institute of Biology, University of Kassel, Germany
| | | | - Christoph Bleidorn
- Molecular Evolution and Animal Systematics, Institute of Biology, University of Leipzig, Germany German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
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Paknia O, Schierwater B. Global Habitat Suitability and Ecological Niche Separation in the Phylum Placozoa. PLoS One 2015; 10:e0140162. [PMID: 26580806 PMCID: PMC4651326 DOI: 10.1371/journal.pone.0140162] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Accepted: 09/10/2015] [Indexed: 02/02/2023] Open
Abstract
The enigmatic placozoans, which hold a key position in the metazoan Tree of Life, have attracted substantial attention in many areas of biological and biomedical research. While placozoans have become an emerging model system, their ecology and particularly biogeography remain widely unknown. In this study, we use modelling approaches to explore habitat preferences, and distribution pattern of the placozoans phylum. We provide hypotheses for discrete ecological niche separation between genetic placozoan lineages, which may also help to understand biogeography patterns in other small marine invertebrates. We, here, used maximum entropy modelling to predict placozoan distribution using 20 environmental grids of 9.2 km2 resolution. In addition, we used recently developed metrics of niche overlap to compare habitat suitability models of three genetic clades. The predicted distributions range from 55°N to 44°S and are restricted to regions of intermediate to warm sea surface temperatures. High concentrations of salinity and low nutrient concentrations appear as secondary factors. Tests of niche equivalency reveal the largest differences between placozoan clades I and III. Interestingly, the genetically well-separated clades I and V appear to be ecologically very similar. Our habitat suitability models predict a wider latitudinal distribution for placozoans, than currently described, especially in the northern hemisphere. With respect to biogeography modelling, placozoans show patterns somewhere between higher metazoan taxa and marine microorganisms, with the first group usually showing complex biogeographies and the second usually showing “no biogeography.”
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Affiliation(s)
- Omid Paknia
- ITZ, Ecology and Evolution, TiHo Hannover, Hannover, Germany
- * E-mail:
| | - Bernd Schierwater
- ITZ, Ecology and Evolution, TiHo Hannover, Hannover, Germany
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, United States of America
- Sackler Institute for Comparative Genomics and Division of Invertebrate Zoology, American Museum of Natural History, New York, New York, United States of America
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Halanych KM. The ctenophore lineage is older than sponges? That cannot be right! Or can it? ACTA ACUST UNITED AC 2015; 218:592-7. [PMID: 25696822 DOI: 10.1242/jeb.111872] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Recent phylogenetic analyses resulting from collection of whole genome data suggest that ctenophores, or comb jellies, are sister to all other animals. Even before publication, this result prompted discussion among researchers. Here, I counter common criticisms raised about this result and show that assumptions placing sponges as the basal-most extant animal lineage are based on limited evidence and questionable premises. For example, the idea that sponges are simple and the reported similarity of sponge choanocytes to Choanflagellata do not provide useful characters for determining the positions of sponges within the animal tree. Intertwined with discussion of basal metazoan phylogeny is consideration of the evolution of neuronal systems. Recent data show that neural systems of ctenophores are vastly different from those of other animals and use different sets of cellular and genetic mechanisms. Thus, neural systems appear to have at least two independent origins regardless of whether ctenophores or sponges are the earliest branching extant animal lineage.
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Affiliation(s)
- Kenneth M Halanych
- Department of Biological Sciences, 101 Life Sciences Building, Auburn University, Auburn, AL 36849, USA Friday Harbor Laboratories, 620 University Road, University of Washington, Friday Harbor, WA 98250, USA
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