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Juretić D. Designed Multifunctional Peptides for Intracellular Targets. Antibiotics (Basel) 2022; 11:antibiotics11091196. [PMID: 36139975 PMCID: PMC9495127 DOI: 10.3390/antibiotics11091196] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 08/25/2022] [Accepted: 08/29/2022] [Indexed: 11/25/2022] Open
Abstract
Nature’s way for bioactive peptides is to provide them with several related functions and the ability to cooperate in performing their job. Natural cell-penetrating peptides (CPP), such as penetratins, inspired the design of multifunctional constructs with CPP ability. This review focuses on known and novel peptides that can easily reach intracellular targets with little or no toxicity to mammalian cells. All peptide candidates were evaluated and ranked according to the predictions of low toxicity to mammalian cells and broad-spectrum activity. The final set of the 20 best peptide candidates contains the peptides optimized for cell-penetrating, antimicrobial, anticancer, antiviral, antifungal, and anti-inflammatory activity. Their predicted features are intrinsic disorder and the ability to acquire an amphipathic structure upon contact with membranes or nucleic acids. In conclusion, the review argues for exploring wide-spectrum multifunctionality for novel nontoxic hybrids with cell-penetrating peptides.
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Affiliation(s)
- Davor Juretić
- Mediterranean Institute for Life Sciences, 21000 Split, Croatia;
- Faculty of Science, University of Split, 21000 Split, Croatia;
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2
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Heger P, Zheng W, Rottmann A, Panfilio KA, Wiehe T. The genetic factors of bilaterian evolution. eLife 2020; 9:e45530. [PMID: 32672535 PMCID: PMC7535936 DOI: 10.7554/elife.45530] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 07/03/2020] [Indexed: 12/13/2022] Open
Abstract
The Cambrian explosion was a unique animal radiation ~540 million years ago that produced the full range of body plans across bilaterians. The genetic mechanisms underlying these events are unknown, leaving a fundamental question in evolutionary biology unanswered. Using large-scale comparative genomics and advanced orthology evaluation techniques, we identified 157 bilaterian-specific genes. They include the entire Nodal pathway, a key regulator of mesoderm development and left-right axis specification; components for nervous system development, including a suite of G-protein-coupled receptors that control physiology and behaviour, the Robo-Slit midline repulsion system, and the neurotrophin signalling system; a high number of zinc finger transcription factors; and novel factors that previously escaped attention. Contradicting the current view, our study reveals that genes with bilaterian origin are robustly associated with key features in extant bilaterians, suggesting a causal relationship.
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Affiliation(s)
- Peter Heger
- Institute for Genetics, Cologne Biocenter, University of CologneCologneGermany
| | - Wen Zheng
- Institute for Genetics, Cologne Biocenter, University of CologneCologneGermany
| | - Anna Rottmann
- Institute for Genetics, Cologne Biocenter, University of CologneCologneGermany
| | - Kristen A Panfilio
- Institute for Zoology: Developmental Biology, Cologne Biocenter, University of CologneCologneGermany
- School of Life Sciences, University of Warwick, Gibbet Hill CampusCoventryUnited Kingdom
| | - Thomas Wiehe
- Institute for Genetics, Cologne Biocenter, University of CologneCologneGermany
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3
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Gąsiorowski L, Hejnol A. Hox gene expression in postmetamorphic juveniles of the brachiopod Terebratalia transversa. EvoDevo 2019; 10:1. [PMID: 30637095 PMCID: PMC6325747 DOI: 10.1186/s13227-018-0114-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 12/22/2018] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Hox genes encode a family of homeodomain containing transcription factors that are clustered together on chromosomes of many Bilateria. Some bilaterian lineages express these genes during embryogenesis in spatial and/or temporal order according to their arrangement in the cluster, a phenomenon referred to as collinearity. Expression of Hox genes is well studied during embryonic and larval development of numerous species; however, relatively few studies focus on the comparison of pre- and postmetamorphic expression of Hox genes in animals with biphasic life cycle. Recently, the expression of Hox genes was described for embryos and larvae of Terebratalia transversa, a rhynchonelliformean brachiopod, which possesses distinct metamorphosis from planktonic larvae to sessile juveniles. During premetamorphic development, T. transversa does not exhibit spatial collinearity and several of its Hox genes are recruited for the morphogenesis of novel structures. In our study, we determined the expression of Hox genes in postmetamorphic juveniles of T. transversa in order to examine metamorphosis-related changes of expression patterns and to test whether Hox genes are expressed in the spatially collinear way in the postmetamorphic juveniles. RESULTS Hox genes are expressed in a spatially non-collinear manner in juveniles, generally showing similar patterns as ones observed in competent larvae: genes labial and post1 are expressed in chaetae-related structures, sex combs reduced in the shell-forming epithelium, whereas lox5 and lox4 in dorso-posterior epidermis. After metamorphosis, expression of genes proboscipedia, hox3, deformed and antennapedia becomes restricted to, respectively, shell musculature, prospective hinge rudiments and pedicle musculature and epidermis. CONCLUSIONS All developmental stages of T. transversa, including postmetamorphic juveniles, exhibit a spatial non-collinear Hox genes expression with only minor changes observed between pre- and postmetamorphic stages. Our results are concordant with morphological observation that metamorphosis in rhynchonelliformean brachiopods, despite being rapid, is rather gradual. The most drastic changes in Hox gene expression patterns observed during metamorphosis could be explained by the inversion of the mantle lobe, which relocates some of the more posterior larval structures into the anterior edge of the juveniles. Co-option of Hox genes for the morphogenesis of novel structures is even more pronounced in postmetamorphic brachiopods when compared to larvae.
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Affiliation(s)
- Ludwik Gąsiorowski
- Sars International Centre for Marine Molecular Biology, University of Bergen, Bergen, Norway
| | - Andreas Hejnol
- Sars International Centre for Marine Molecular Biology, University of Bergen, Bergen, Norway
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4
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Jouhilahti EM, Madissoon E, Vesterlund L, Töhönen V, Krjutškov K, Plaza Reyes A, Petropoulos S, Månsson R, Linnarsson S, Bürglin T, Lanner F, Hovatta O, Katayama S, Kere J. The human PRD-like homeobox gene LEUTX has a central role in embryo genome activation. Development 2016; 143:3459-3469. [PMID: 27578796 PMCID: PMC5087614 DOI: 10.1242/dev.134510] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Accepted: 08/12/2016] [Indexed: 12/13/2022]
Abstract
Leucine twenty homeobox (LEUTX) is a paired (PRD)-like homeobox gene that is expressed almost exclusively in human embryos during preimplantation development. We previously identified a novel transcription start site for the predicted human LEUTX gene based on the transcriptional analysis of human preimplantation embryos. The novel variant encodes a protein with a complete homeodomain. Here, we provide a detailed description of the molecular cloning of the complete homeodomain-containing LEUTX Using a human embryonic stem cell overexpression model we show that the complete homeodomain isoform is functional and sufficient to activate the transcription of a large proportion of the genes that are upregulated in human embryo genome activation (EGA), whereas the previously predicted partial homeodomain isoform is largely inactive. Another PRD-like transcription factor, DPRX, is then upregulated as a powerful repressor of transcription. We propose a two-stage model of human EGA in which LEUTX acts as a transcriptional activator at the 4-cell stage, and DPRX as a balancing repressor at the 8-cell stage. We conclude that LEUTX is a candidate regulator of human EGA.
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Affiliation(s)
- Eeva-Mari Jouhilahti
- Department of Biosciences and Nutrition, Karolinska Institutet, Novum, Huddinge 141 83, Sweden
| | - Elo Madissoon
- Department of Biosciences and Nutrition, Karolinska Institutet, Novum, Huddinge 141 83, Sweden
| | - Liselotte Vesterlund
- Department of Biosciences and Nutrition, Karolinska Institutet, Novum, Huddinge 141 83, Sweden
| | - Virpi Töhönen
- Department of Biosciences and Nutrition, Karolinska Institutet, Novum, Huddinge 141 83, Sweden
| | - Kaarel Krjutškov
- Department of Biosciences and Nutrition, Karolinska Institutet, Novum, Huddinge 141 83, Sweden Competence Centre on Health Technologies, Tartu 50410, Estonia
| | - Alvaro Plaza Reyes
- Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Karolinska University Hospital Huddinge, Stockholm 141 86, Sweden
| | - Sophie Petropoulos
- Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Karolinska University Hospital Huddinge, Stockholm 141 86, Sweden
| | - Robert Månsson
- Center for Hematology and Regenerative Medicine Huddinge, Karolinska Institute, Stockholm 14183, Sweden
| | - Sten Linnarsson
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm 171 77, Sweden
| | - Thomas Bürglin
- Department of Biomedicine, University of Basel, Basel 4058, Switzerland
| | - Fredrik Lanner
- Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Karolinska University Hospital Huddinge, Stockholm 141 86, Sweden
| | - Outi Hovatta
- Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Karolinska University Hospital Huddinge, Stockholm 141 86, Sweden
| | - Shintaro Katayama
- Department of Biosciences and Nutrition, Karolinska Institutet, Novum, Huddinge 141 83, Sweden
| | - Juha Kere
- Department of Biosciences and Nutrition, Karolinska Institutet, Novum, Huddinge 141 83, Sweden Science for Life Laboratory, Tomtebodavägen 23 A, Solna 171 21, Sweden Molecular Neurology Research Program, University of Helsinki and Folkhälsan Institute of Genetics, Biomedicum 1, Haartmaninkatu 8, Helsinki 00290, Finland
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5
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Schierwater B, Holland PWH, Miller DJ, Stadler PF, Wiegmann BM, Wörheide G, Wray GA, DeSalle R. Never Ending Analysis of a Century Old Evolutionary Debate: “Unringing” the Urmetazoon Bell. Front Ecol Evol 2016. [DOI: 10.3389/fevo.2016.00005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Zwarycz AS, Nossa CW, Putnam NH, Ryan JF. Timing and Scope of Genomic Expansion within Annelida: Evidence from Homeoboxes in the Genome of the Earthworm Eisenia fetida. Genome Biol Evol 2016. [DOI: 10.1093/gbe/evv243 v] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Zwarycz AS, Nossa CW, Putnam NH, Ryan JF. Timing and Scope of Genomic Expansion within Annelida: Evidence from Homeoboxes in the Genome of the Earthworm Eisenia fetida. Genome Biol Evol 2015; 8:271-81. [PMID: 26659921 PMCID: PMC4758240 DOI: 10.1093/gbe/evv243] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/30/2015] [Indexed: 11/14/2022] Open
Abstract
Annelida represents a large and morphologically diverse group of bilaterian organisms. The recently published polychaete and leech genome sequences revealed an equally dynamic range of diversity at the genomic level. The availability of more annelid genomes will allow for the identification of evolutionary genomic events that helped shape the annelid lineage and better understand the diversity within the group. We sequenced and assembled the genome of the common earthworm, Eisenia fetida. As a first pass at understanding the diversity within the group, we classified 363 earthworm homeoboxes and compared them with those of the leech Helobdella robusta and the polychaete Capitella teleta. We inferred many gene expansions occurring in the lineage connecting the most recent common ancestor (MRCA) of Capitella and Eisenia to the Eisenia/Helobdella MRCA. Likewise, the lineage leading from the Eisenia/Helobdella MRCA to the leech H. robusta has experienced substantial gains and losses. However, the lineage leading from Eisenia/Helobdella MRCA to E. fetida is characterized by extraordinary levels of homeobox gain. The evolutionary dynamics observed in the homeoboxes of these lineages are very likely to be generalizable to all genes. These genome expansions and losses have likely contributed to the remarkable biology exhibited in this group. These results provide a new perspective from which to understand the diversity within these lineages, show the utility of sub-draft genome assemblies for understanding genomic evolution, and provide a critical resource from which the biology of these animals can be studied.
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Affiliation(s)
- Allison S Zwarycz
- Whitney Laboratory for Marine Bioscience, University of Florida Viterbo University
| | - Carlos W Nossa
- Department of Ecology and Evolutionary Biology, Rice University
| | | | - Joseph F Ryan
- Whitney Laboratory for Marine Bioscience, University of Florida Department of Biology, University of Florida
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Ferrier DEK. The origin of the Hox/ParaHox genes, the Ghost Locus hypothesis and the complexity of the first animal. Brief Funct Genomics 2015; 15:333-41. [PMID: 26637506 DOI: 10.1093/bfgp/elv056] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
A key aim in evolutionary biology is to deduce ancestral states to better understand the evolutionary origins of clades of interest and the diversification process(es) that has/have elaborated them. These ancestral deductions can hit difficulties when undetected loss events are misinterpreted as ancestral absences. With the ever-increasing amounts of animal genomic sequence data, we are gaining a much clearer view of the preponderance of differential gene losses across animal lineages. This has become particularly clear with recent progress in our understanding of the origins of the Hox/ParaHox developmental control genes relative to the earliest branching lineages of the animal kingdom: the sponges (Porifera), comb jellies (Ctenophora) and placozoans (Placozoa). These reassessments of the diversity and complexity of developmental control genes in the earliest animal ancestors need to go hand-in-hand with complementary advances in comparative morphology, phylogenetics and palaeontology to clarify our understanding of the complexity of the last common ancestor of all animals. The field is currently undergoing a shift from the traditional consensus of a sponge-like animal ancestor from which morphological and molecular elaboration subsequently evolved, to a scenario of a more complex animal ancestor, with subsequent losses and simplifications in various lineages.
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Abstract
The non-bilaterian animals comprise organisms in the phyla Porifera, Cnidaria, Ctenophora and Placozoa. These early-diverging phyla are pivotal to understanding the evolution of bilaterian animals. After the exponential increase in research in evolutionary development (evo-devo) in the last two decades, these organisms are again in the spotlight of evolutionary biology. In this work, I briefly review some aspects of the developmental biology of nonbilaterians that contribute to understanding the evolution of development and of the metazoans. The evolution of the developmental genetic toolkit, embryonic polarization, the origin of gastrulation and mesodermal cells, and the origin of neural cells are discussed. The possibility that germline and stem cell lineages have the same origin is also examined. Although a considerable number of non-bilaterian species are already being investigated, the use of species belonging to different branches of non-bilaterian lineages and functional experimentation with gene manipulation in the majority of the non-bilaterian lineages will be necessary for further progress in this field.
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Affiliation(s)
- Emilio Lanna
- Departamento de Biologia Geral, Instituto de Biologia, Universidade Federal da Bahia, Salvador, BA, Brazil
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10
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Biscotti MA, Canapa A, Forconi M, Barucca M. HoxandParaHoxgenes: A review on molluscs. Genesis 2014; 52:935-45. [DOI: 10.1002/dvg.22839] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 11/10/2014] [Accepted: 11/11/2014] [Indexed: 01/28/2023]
Affiliation(s)
- Maria Assunta Biscotti
- Dipartimento di Scienze della Vita e dell'Ambiente; Università Politecnica delle Marche; Ancona Italy
| | - Adriana Canapa
- Dipartimento di Scienze della Vita e dell'Ambiente; Università Politecnica delle Marche; Ancona Italy
| | - Mariko Forconi
- Dipartimento di Scienze della Vita e dell'Ambiente; Università Politecnica delle Marche; Ancona Italy
| | - Marco Barucca
- Dipartimento di Scienze della Vita e dell'Ambiente; Università Politecnica delle Marche; Ancona Italy
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Abstract
Trichoplax adhaerens is an enigmatic basal animal with an extraordinarily simple morphological organization and surprisingly complex behaviors. Basic morphological, molecular and behavioral work is essential to better understand the unique and curious life style of these organisms. We provide basic instructions on how Trichoplax can be cultured and studied in the laboratory emphasizing behavioral and cellular aspects.
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12
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Holland PWH. Evolution of homeobox genes. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2012; 2:31-45. [DOI: 10.1002/wdev.78] [Citation(s) in RCA: 179] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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13
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McDougall C, Korchagina N, Tobin JL, Ferrier DE. Annelid Distal-less/Dlx duplications reveal varied post-duplication fates. BMC Evol Biol 2011; 11:241. [PMID: 21846345 PMCID: PMC3199776 DOI: 10.1186/1471-2148-11-241] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Accepted: 08/16/2011] [Indexed: 11/24/2022] Open
Abstract
Background Dlx (Distal-less) genes have various developmental roles and are widespread throughout the animal kingdom, usually occurring as single copy genes in non-chordates and as multiple copies in most chordate genomes. While the genomic arrangement and function of these genes is well known in vertebrates and arthropods, information about Dlx genes in other organisms is scarce. We investigate the presence of Dlx genes in several annelid species and examine Dlx gene expression in the polychaete Pomatoceros lamarckii. Results Two Dlx genes are present in P. lamarckii, Capitella teleta and Helobdella robusta. The C. teleta Dlx genes are closely linked in an inverted tail-to-tail orientation, reminiscent of the arrangement of vertebrate Dlx pairs, and gene conversion appears to have had a role in their evolution. The H. robusta Dlx genes, however, are not on the same genomic scaffold and display divergent sequences, while, if the P. lamarckii genes are linked in a tail-to-tail orientation they are a minimum of 41 kilobases apart and show no sign of gene conversion. No expression in P. lamarckii appendage development has been observed, which conflicts with the supposed conserved role of these genes in animal appendage development. These Dlx duplications do not appear to be annelid-wide, as the polychaete Platynereis dumerilii likely possesses only one Dlx gene. Conclusions On the basis of the currently accepted annelid phylogeny, we hypothesise that one Dlx duplication occurred in the annelid lineage after the divergence of P. dumerilii from the other lineages and these duplicates then had varied evolutionary fates in different species. We also propose that the ancestral role of Dlx genes is not related to appendage development.
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Affiliation(s)
- Carmel McDougall
- The Scottish Oceans Institute, University of St Andrews, East Sands, St Andrews KY168LB, UK.
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Hui JHL, McDougall C, Monteiro AS, Holland PWH, Arendt D, Balavoine G, Ferrier DEK. Extensive chordate and annelid macrosynteny reveals ancestral homeobox gene organization. Mol Biol Evol 2011; 29:157-65. [PMID: 21727239 DOI: 10.1093/molbev/msr175] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Genes with the homeobox motif are crucial in developmental biology and widely implicated in the evolution of development. The Antennapedia (ANTP)-class is one of the two major classes of animal homeobox genes, and includes the Hox genes, renowned for their role in patterning the anterior-posterior axis of animals. The origin and evolution of the ANTP-class genes are a matter of some debate. A principal guiding hypothesis has been the existence of an ancient gene Mega-cluster deep in animal ancestry. This hypothesis was largely established from linkage data from chordates, and the Mega-cluster hypothesis remains to be seriously tested in protostomes. We have thus mapped ANTP-class homeobox genes to the chromosome level in a lophotrochozoan protostome. Our comparison of gene organization in Platynereis dumerilii and chordates indicates that the Mega-cluster, if it did exist, had already been broken up onto four chromosomes by the time of the protostome-deuterostome ancestor (PDA). These results not only elucidate an aspect of the genome organization of the PDA but also reveal high levels of macrosynteny between P. dumerilii and chordates. This implies a very low rate of interchromosomal genome rearrangement in the lineages leading to P. dumerilii and the chordate ancestor since the time of the PDA.
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Affiliation(s)
- Jerome H L Hui
- Department of Zoology, University of Oxford, Oxford, United Kingdom
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Ryan JF, Pang K, Mullikin JC, Martindale MQ, Baxevanis AD. The homeodomain complement of the ctenophore Mnemiopsis leidyi suggests that Ctenophora and Porifera diverged prior to the ParaHoxozoa. EvoDevo 2010; 1:9. [PMID: 20920347 PMCID: PMC2959044 DOI: 10.1186/2041-9139-1-9] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2010] [Accepted: 10/04/2010] [Indexed: 11/10/2022] Open
Abstract
Background The much-debated phylogenetic relationships of the five early branching metazoan lineages (Bilateria, Cnidaria, Ctenophora, Placozoa and Porifera) are of fundamental importance in piecing together events that occurred early in animal evolution. Comparisons of gene content between organismal lineages have been identified as a potentially useful methodology for phylogenetic reconstruction. However, these comparisons require complete genomes that, until now, did not exist for the ctenophore lineage. The homeobox superfamily of genes is particularly suited for these kinds of gene content comparisons, since it is large, diverse, and features a highly conserved domain. Results We have used a next-generation sequencing approach to generate a high-quality rough draft of the genome of the ctenophore Mnemiopsis leidyi and subsequently identified a set of 76 homeobox-containing genes from this draft. We phylogenetically categorized this set into established gene families and classes and then compared this set to the homeodomain repertoire of species from the other four early branching metazoan lineages. We have identified several important classes and subclasses of homeodomains that appear to be absent from Mnemiopsis and from the poriferan Amphimedon queenslandica. We have also determined that, based on lineage-specific paralog retention and average branch lengths, it is unlikely that these missing classes and subclasses are due to extensive gene loss or unusually high rates of evolution in Mnemiopsis. Conclusions This paper provides a first glimpse of the first sequenced ctenophore genome. We have characterized the full complement of Mnemiopsis homeodomains from this species and have compared them to species from other early branching lineages. Our results suggest that Porifera and Ctenophora were the first two extant lineages to diverge from the rest of animals. Based on this analysis, we also propose a new name - ParaHoxozoa - for the remaining group that includes Placozoa, Cnidaria and Bilateria.
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Affiliation(s)
- Joseph F Ryan
- Genome Technology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA.
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16
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Sperling EA, Vinther J. A placozoan affinity for Dickinsonia and the evolution of late Proterozoic metazoan feeding modes. Evol Dev 2010; 12:201-9. [PMID: 20433459 DOI: 10.1111/j.1525-142x.2010.00404.x] [Citation(s) in RCA: 136] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Dickinsonia is one of the most recognizable forms in the Ediacaran fauna, but its phylogenetic position has been contentious, and it has been placed in almost every kingdom of life. Here, it is hypothesized that the affinities of Dickinsonia lie with the Placozoa (Metazoa), an understudied phylum that is widespread in tropical seas worldwide. Modern placozoans show obvious differences in size and axial organization compared with Dickinsonia, but these differences can be accounted for by the stem-group/crown-group distinction. The affinity with placozoans is evidenced primarily by the unique feeding mode of Dickinsonia, which is demonstrated by a series of feeding traces. These traces indicate that Dickinsonia moved over the Ediacaran matgrounds, and digested the mat using its entire lower sole. The ability of Dickinsonia to move negates an algal, fungal, or sponge affinity, while the feeding mode, external digestion with a ventral sole, rules out placement within any sponge or eumetazoan lineage. The only organisms that both move and feed in this manner are placozoans. Recent molecular phylogenetic studies have demonstrated that placozoans lie above sponges but below Eumetazoa. We hypothesize that Dickinsonia and other externally digesting Ediacaran forms are either stem-placozoans, or a series of extinct lineages above sponges and below eumetazoans on the metazoan tree. We discuss the potential evolutionary transitions between the main metazoan feeding modes in the context of the emerging molecular phylogeny, and suggest that aspects of the sponge and placozoan feeding strategies are relicts of nonuniformitarian Proterozoic ocean conditions.
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Affiliation(s)
- Erik A Sperling
- Department of Geology and Geophysics, Yale University, New Haven, CT 06520, USA.
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Fonseca NA, Vieira CP, Vieira J. Gene classification based on amino acid motifs and residues: the DLX (distal-less) test case. PLoS One 2009; 4:e5748. [PMID: 19484130 PMCID: PMC2685005 DOI: 10.1371/journal.pone.0005748] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2008] [Accepted: 05/04/2009] [Indexed: 01/18/2023] Open
Abstract
Background Comparative studies using hundreds of sequences can give a detailed picture of the evolution of a given gene family. Nevertheless, retrieving only the sequences of interest from public databases can be difficult, in particular, when working with highly divergent sequences. The difficulty increases substantially when one wants to include in the study sequences from many (or less well studied) species whose genomes are non-annotated or incompletely annotated. Methodology/Principal Findings In this work we evaluate the usefulness of different approaches of gene retrieval and classification, using the distal-less (DLX) gene family as a test case. Furthermore, we evaluate whether the use of a large number of gene sequences from a wide range of animal species, the use of multiple alternative alignments, and the use of amino acids aligned with high confidence only, is enough to recover the accepted DLX evolutionary history. Conclusions/Significance The canonical DLX homeobox gene sequence here derived, together with the characteristic amino acid variants here identified in the DLX homeodomain region, can be used to retrieve and classify DLX genes in a simple and efficient way. A program is made available that allows the easy retrieval of synteny information that can be used to classify gene sequences. Maximum likelihood trees using hundreds of sequences can be used for gene identification. Nevertheless, for the DLX case, the proposed DLX evolutionary is not recovered even when multiple alignment algorithms are used.
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Affiliation(s)
- Nuno A. Fonseca
- Instituto de Biologia Molecular e Celular (IBMC); University of Porto, Porto, Portugal
- CRACS-INESC Porto, Universidade do Porto, Porto, Portugal
| | - Cristina P. Vieira
- Instituto de Biologia Molecular e Celular (IBMC); University of Porto, Porto, Portugal
| | - Jorge Vieira
- Instituto de Biologia Molecular e Celular (IBMC); University of Porto, Porto, Portugal
- * E-mail:
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Manuel M. Early evolution of symmetry and polarity in metazoan body plans. C R Biol 2009; 332:184-209. [DOI: 10.1016/j.crvi.2008.07.009] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2008] [Accepted: 07/21/2008] [Indexed: 10/21/2022]
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Chiori R, Jager M, Denker E, Wincker P, Da Silva C, Le Guyader H, Manuel M, Quéinnec E. Are Hox genes ancestrally involved in axial patterning? Evidence from the hydrozoan Clytia hemisphaerica (Cnidaria). PLoS One 2009; 4:e4231. [PMID: 19156208 PMCID: PMC2626245 DOI: 10.1371/journal.pone.0004231] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2008] [Accepted: 12/05/2008] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND The early evolution and diversification of Hox-related genes in eumetazoans has been the subject of conflicting hypotheses concerning the evolutionary conservation of their role in axial patterning and the pre-bilaterian origin of the Hox and ParaHox clusters. The diversification of Hox/ParaHox genes clearly predates the origin of bilaterians. However, the existence of a "Hox code" predating the cnidarian-bilaterian ancestor and supporting the deep homology of axes is more controversial. This assumption was mainly based on the interpretation of Hox expression data from the sea anemone, but growing evidence from other cnidarian taxa puts into question this hypothesis. METHODOLOGY/PRINCIPAL FINDINGS Hox, ParaHox and Hox-related genes have been investigated here by phylogenetic analysis and in situ hybridisation in Clytia hemisphaerica, an hydrozoan species with medusa and polyp stages alternating in the life cycle. Our phylogenetic analyses do not support an origin of ParaHox and Hox genes by duplication of an ancestral ProtoHox cluster, and reveal a diversification of the cnidarian HOX9-14 genes into three groups called A, B, C. Among the 7 examined genes, only those belonging to the HOX9-14 and the CDX groups exhibit a restricted expression along the oral-aboral axis during development and in the planula larva, while the others are expressed in very specialised areas at the medusa stage. CONCLUSIONS/SIGNIFICANCE Cross species comparison reveals a strong variability of gene expression along the oral-aboral axis and during the life cycle among cnidarian lineages. The most parsimonious interpretation is that the Hox code, collinearity and conservative role along the antero-posterior axis are bilaterian innovations.
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Affiliation(s)
- Roxane Chiori
- UPMC Univ Paris 06, UMR 7138 CNRS UPMC MNHN IRD, Case 05, Paris, France
| | - Muriel Jager
- UPMC Univ Paris 06, UMR 7138 CNRS UPMC MNHN IRD, Case 05, Paris, France
| | - Elsa Denker
- Sars International Centre for Marine Molecular Biology, Bergen, Norway
| | | | | | - Hervé Le Guyader
- UPMC Univ Paris 06, UMR 7138 CNRS UPMC MNHN IRD, Case 05, Paris, France
| | - Michaël Manuel
- UPMC Univ Paris 06, UMR 7138 CNRS UPMC MNHN IRD, Case 05, Paris, France
| | - Eric Quéinnec
- UPMC Univ Paris 06, UMR 7138 CNRS UPMC MNHN IRD, Case 05, Paris, France
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20
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Hemmrich G, Bosch TC. Compagen, a comparative genomics platform for early branching metazoan animals, reveals early origins of genes regulating stem-cell differentiation. Bioessays 2008; 30:1010-8. [DOI: 10.1002/bies.20813] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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21
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Schierwater B, Kamm K, Srivastava M, Rokhsar D, Rosengarten RD, Dellaporta SL. The early ANTP gene repertoire: insights from the placozoan genome. PLoS One 2008; 3:e2457. [PMID: 18716659 PMCID: PMC2515636 DOI: 10.1371/journal.pone.0002457] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2008] [Accepted: 04/29/2008] [Indexed: 11/18/2022] Open
Abstract
The evolution of ANTP genes in the Metazoa has been the subject of conflicting hypotheses derived from full or partial gene sequences and genomic organization in higher animals. Whole genome sequences have recently filled in some crucial gaps for the basal metazoan phyla Cnidaria and Porifera. Here we analyze the complete genome of Trichoplax adhaerens, representing the basal metazoan phylum Placozoa, for its set of ANTP class genes. The Trichoplax genome encodes representatives of Hox/ParaHox-like, NKL, and extended Hox genes. This repertoire possibly mirrors the condition of a hypothetical cnidarian-bilaterian ancestor. The evolution of the cnidarian and bilaterian ANTP gene repertoires can be deduced by a limited number of cis-duplications of NKL and “extended Hox” genes and the presence of a single ancestral “ProtoHox” gene.
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Affiliation(s)
- Bernd Schierwater
- Division of Ecology and Evolution, Stiftung Tieraerztliche Hochschule Hannover, Hannover, Germany
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut, United States of America
| | - Kai Kamm
- Division of Ecology and Evolution, Stiftung Tieraerztliche Hochschule Hannover, Hannover, Germany
- * E-mail:
| | - Mansi Srivastava
- Center for Integrative Genomics and Department of Molecular and Cell Biology, University of California, Berkeley, California, United States of America
| | - Daniel Rokhsar
- Department of Energy, Joint Genome Institute, Walnut Creek, California, United States of America
- Center for Integrative Genomics and Department of Molecular and Cell Biology, University of California, Berkeley, California, United States of America
| | - Rafael D. Rosengarten
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut, United States of America
| | - Stephen L. Dellaporta
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut, United States of America
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22
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The Trichoplax genome and the nature of placozoans. Nature 2008; 454:955-60. [PMID: 18719581 DOI: 10.1038/nature07191] [Citation(s) in RCA: 620] [Impact Index Per Article: 38.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2008] [Accepted: 06/23/2008] [Indexed: 11/08/2022]
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23
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Pang K, Martindale MQ. Developmental expression of homeobox genes in the ctenophore Mnemiopsis leidyi. Dev Genes Evol 2008; 218:307-19. [PMID: 18504608 DOI: 10.1007/s00427-008-0222-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2008] [Accepted: 04/14/2008] [Indexed: 11/28/2022]
Affiliation(s)
- Kevin Pang
- Kewalo Marine Laboratory, Pacific Biosciences Research Center, University of Hawaii, 41 Ahui Street, Honolulu, HI 96813, USA
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24
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Ruiz-Trillo I, Roger AJ, Burger G, Gray MW, Lang BF. A phylogenomic investigation into the origin of metazoa. Mol Biol Evol 2008; 25:664-72. [PMID: 18184723 DOI: 10.1093/molbev/msn006] [Citation(s) in RCA: 175] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The evolution of multicellular animals (Metazoa) from their unicellular ancestors was a key transition that was accompanied by the emergence and diversification of gene families associated with multicellularity. To clarify the timing and order of specific events in this transition, we conducted expressed sequence tag surveys on 4 putative protistan relatives of Metazoa including the choanoflagellate Monosiga ovata, the ichthyosporeans Sphaeroforma arctica and Amoebidium parasiticum, and the amoeba Capsaspora owczarzaki, and 2 members of Amoebozoa, Acanthamoeba castellanii and Mastigamoeba balamuthi. We find that homologs of genes involved in metazoan multicellularity exist in several of these unicellular organisms, including 1 encoding a membrane-associated guanylate kinase with an inverted arrangement of protein-protein interaction domains (MAGI) in Capsaspora. In Metazoa, MAGI regulates tight junctions involved in cell-cell communication. By phylogenomic analyses of genes encoded in nuclear and mitochondrial genomes, we show that the choanoflagellates are the closest relatives of the Metazoa, followed by the Capsaspora and Ichthyosporea lineages, although the branching order between the latter 2 groups remains unclear. Understanding the function of "metazoan-specific" proteins we have identified in these protists will clarify the evolutionary steps that led to the emergence of the Metazoa.
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Affiliation(s)
- Iñaki Ruiz-Trillo
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Canada.
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25
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Holland PWH, Booth HAF, Bruford EA. Classification and nomenclature of all human homeobox genes. BMC Biol 2007; 5:47. [PMID: 17963489 PMCID: PMC2211742 DOI: 10.1186/1741-7007-5-47] [Citation(s) in RCA: 289] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2007] [Accepted: 10/26/2007] [Indexed: 12/19/2022] Open
Abstract
Background The homeobox genes are a large and diverse group of genes, many of which play important roles in the embryonic development of animals. Increasingly, homeobox genes are being compared between genomes in an attempt to understand the evolution of animal development. Despite their importance, the full diversity of human homeobox genes has not previously been described. Results We have identified all homeobox genes and pseudogenes in the euchromatic regions of the human genome, finding many unannotated, incorrectly annotated, unnamed, misnamed or misclassified genes and pseudogenes. We describe 300 human homeobox loci, which we divide into 235 probable functional genes and 65 probable pseudogenes. These totals include 3 genes with partial homeoboxes and 13 pseudogenes that lack homeoboxes but are clearly derived from homeobox genes. These figures exclude the repetitive DUX1 to DUX5 homeobox sequences of which we identified 35 probable pseudogenes, with many more expected in heterochromatic regions. Nomenclature is established for approximately 40 formerly unnamed loci, reflecting their evolutionary relationships to other loci in human and other species, and nomenclature revisions are proposed for around 30 other loci. We use a classification that recognizes 11 homeobox gene 'classes' subdivided into 102 homeobox gene 'families'. Conclusion We have conducted a comprehensive survey of homeobox genes and pseudogenes in the human genome, described many new loci, and revised the classification and nomenclature of homeobox genes. The classification scheme may be widely applicable to homeobox genes in other animal genomes and will facilitate comparative genomics of this important gene superclass.
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Affiliation(s)
- Peter W H Holland
- Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK.
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26
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Affiliation(s)
- Kevin J Peterson
- Department of Biological Sciences, Dartmouth College, Hanover, NH 03755, USA.
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27
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Larroux C, Fahey B, Degnan SM, Adamski M, Rokhsar DS, Degnan BM. The NK homeobox gene cluster predates the origin of Hox genes. Curr Biol 2007; 17:706-10. [PMID: 17379523 DOI: 10.1016/j.cub.2007.03.008] [Citation(s) in RCA: 124] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2006] [Revised: 02/28/2007] [Accepted: 03/01/2007] [Indexed: 11/17/2022]
Abstract
Hox and other Antennapedia (ANTP)-like homeobox gene subclasses - ParaHox, EHGbox, and NK-like - contribute to key developmental events in bilaterians [1-4]. Evidence of physical clustering of ANTP genes in multiple animal genomes [4-9] suggests that all four subclasses arose via sequential cis-duplication events. Here, we show that Hox genes' origin occurred after the divergence of sponge and eumetazoan lineages and occurred concomitantly with a major evolutionary transition in animal body-plan complexity. By using whole genome information from the demosponge Amphimedon queenslandica, we provide the first conclusive evidence that the earliest metazoans possessed multiple NK-like genes but no Hox, ParaHox, or EHGbox genes. Six of the eight NK-like genes present in the Amphimedon genome are clustered within 71 kb in an order akin to bilaterian NK clusters. We infer that the NK cluster in the last common ancestor to sponges, cnidarians, and bilaterians consisted of at least five genes. It appears that the ProtoHox gene originated from within this ancestral cluster after the divergence of sponge and eumetazoan lineages. The maintenance of the NK cluster in sponges and bilaterians for greater than 550 million years is likely to reflect regulatory constraints inherent to the organization of this ancient cluster.
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Affiliation(s)
- Claire Larroux
- School of Integrative Biology, The University of Queensland, Brisbane Qld 4072, Australia
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28
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Kamm K, Schierwater B. Ancient complexity of the non-Hox ANTP gene complement in the anthozoan Nematostella vectensis: implications for the evolution of the ANTP superclass. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2007; 306:589-96. [PMID: 16838293 DOI: 10.1002/jez.b.21123] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The origin and evolution of ANTP superclass genes has raised controversial discussions. While recent evidence suggests that a true Hox cluster emerged after the cnidarian bilaterian split, the origin of the ANTP superclass as a whole remains unclear. Based on analyses of bilaterian genomes, it seems very likely that clustering has once been a characteristic of all ANTP homeobox genes and that their ancestors have emerged through several series of cis-duplications from the same genomic region. Since the diploblastic Cnidaria possess orthologs of some non-Hox ANTP genes, at least some steps of the expansion of this hypothetical homeobox gene array must have occurred in the last common ancestor of both lineages--but it is unknown to what extent. By screening the unassembled Nematostella genome, we have identified unambiguous orthologs to almost all non-Hox ANTP genes which are present in Bilateria--with the exception of En, Tlx and (possibly) Vax. Furthermore, Nematostella possesses ANTP genes that are missing in some bilaterian lineages, like the rough gene or NK7. In addition, several ANTP homeobox gene families have been independently duplicated in Nematostella. We conclude that the last cnidarian/bilaterian ancestor already harboured the almost full complement of non-Hox ANTP genes before the Hox system evolved.
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Affiliation(s)
- Kai Kamm
- ITZ, Ecology and Evolution, TiHo Hannover, Hannover, Germany
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29
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Derelle R, Manuel M. Ancient connection between NKL genes and the mesoderm? Insights from Tlx expression in a ctenophore. Dev Genes Evol 2007; 217:253-61. [PMID: 17285344 DOI: 10.1007/s00427-007-0131-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2006] [Accepted: 01/09/2007] [Indexed: 01/15/2023]
Abstract
In recent years, evo-devo studies on non-bilaterian metazoans have improved our understanding of the early evolution of animal body plans. In particular, works on cnidarians suggested that contrary to classical views, the mesoderm originated far before the emergence of the Bilateria. In this context, a synthesis of genomic and functional data concerning the Antennapedia (Antp) superclass of homeobox genes suggested that early in animal evolution, each of the three germ layers was under the control of one cluster of Antp genes. In particular, the patterning and differentiation of the mesoderm was under the control of the NKL cluster. The ctenophores stand as a key taxon with respect to such issues because unlike other non-bilaterian phyla, their intermediate germ layer satisfies the strict embryological definition of a mesoderm. For that reason, we investigated the only known member of the NKL group in Ctenophora, a gene previously isolated from Pleurobrachia and attributed to the Tlx family. In our analysis of the NKL group, this ctenophore gene branches as the sister-group of bilaterian Tlx genes, but without statistical support. The expression pattern of this gene was revealed by in situ hybridisation in the adult ctenophore. The expression territories of PpiTlx are predominantly ectodermal, in two distinct types of ciliated epidermal cells and in one category of gland cells. We also identified a probable endodermal site of expression. Because we failed to detect any mesodermal expression, the results do not provide support to the hypothesis of an ancient functional association between the NKL group and the mesoderm.
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Affiliation(s)
- Romain Derelle
- UMR 7138 CNRS UPMC MNHN IRD, Université Pierre et Marie Curie-Paris 6, Case 05, 7 quai St Bernard, 75005 Paris, France
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Chourrout D, Delsuc F, Chourrout P, Edvardsen RB, Rentzsch F, Renfer E, Jensen MF, Zhu B, de Jong P, Steele RE, Technau U. Minimal ProtoHox cluster inferred from bilaterian and cnidarian Hox complements. Nature 2006; 442:684-7. [PMID: 16900199 DOI: 10.1038/nature04863] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2006] [Accepted: 05/08/2006] [Indexed: 11/09/2022]
Abstract
Bilaterian animals have a Hox gene cluster essential for patterning the main body axis, and a ParaHox gene cluster. Comparison of Hox and ParaHox genes has led workers to postulate that both clusters originated from the duplication of an ancient cluster named ProtoHox, which contained up to four genes with at least the precursors of anterior and posterior Hox/ParaHox genes. However, the way in which genes diversified within the ProtoHox, Hox and ParaHox clusters remains unclear because no systematic study of non-bilaterian animals exists. Here we characterize the full Hox/ParaHox gene complements and genomic organization in two cnidarian species (Nematostella vectensis and Hydra magnipapillata), and suggest a ProtoHox cluster simpler than originally thought on the basis of three arguments. First, both species possess bilaterian-like anterior Hox genes, but their non-anterior genes do not appear as counterparts of either bilaterian central or posterior genes; second, two clustered ParaHox genes, Gsx and a gene related to Xlox and Cdx, are found in Nematostella vectensis; and third, we do not find clear phylogenetic support for a common origin of bilaterian Cdx and posterior genes, which might therefore have appeared after the ProtoHox cluster duplication. Consequently, the ProtoHox cluster might have consisted of only two anterior genes. Non-anterior genes could have appeared independently in the Hox and ParaHox clusters, possibly after the separation of bilaterians and cnidarians.
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Affiliation(s)
- D Chourrout
- Sars International Centre for Marine Molecular Biology, University of Bergen, Thormoehlensgt. 55, 5008 Bergen, Norway.
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Abstract
This primer briefly describes four emerging animal model systems that promise to provide insights into specific aspects of developmental biology. Highlighted here are two relatively well-characterized model systems, Gasterosteus aculeatus (three-spine stickleback fish) and Schmidtea mediterranea (planarian), as well as two organisms on which research is in its infancy, Carollia perspicillata (short-tailed fruit bat), and the basal metazoan, Trichoplax adhaerens. Scientists who helped develop these species into model systems discuss why they chose to research these animals.
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Affiliation(s)
- Julie C Kiefer
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, Utah, USA.
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