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1.
Adv Protein Chem Struct Biol ; 116: 421-449, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31036299

RESUMO

Cell-to-cell signaling is responsible for regulation of many developmental processes such as proliferation, cell migration, survival, cell fate specification and axis patterning. In this article we discussed the role of signaling in the metamorphosis of sponges with a focus on epithelial-mesenchymal transition (EMT) accompanying this event. Sponges (Porifera) are an ancient lineage of morphologically simple animals occupying a basal position on the tree of life. The study of these animals is necessary for understanding the origin of multicellularity and the evolution of developmental processes. Development of sponges is quite diverse. It finishes with the metamorphosis of a free-swimming larva into a young settled sponge. The outer surface of sponge larvae consists of a ciliated epithelial sheath, which ensures locomotion, while their internal structure varies from genus to genus. The fate of larval ciliated cells is the most intriguing aspect of metamorphosis. In this review we discuss the fate of larval ciliated cells, the processes going on in cells during metamorphosis at the molecular level and the regulation of this process. The review is based on information about several sponge species with a focus on Halisarca dujardini, Sycon ciliatum and Amphimedon queenslandica. In our model sponge, H. dujardini, ciliated cells leave the larval epithelium during metamorphosis and migrate to the internal cell mass as amoeboid cells to be differentiated into choanocytes of the juvenile sponge. Ciliated cells undergo EMT and internalize within minutes. As EMT involves the disappearance of adherens junctions and as cadherin, the main adherens junction protein, was identified in the transcriptome of several sponges, we suppose that EMT is regulated through cadherin-containing adherens junctions between ciliated cells. We failed to identify the master genes of EMT in the H. dujardini transcriptome, possibly because transcription was absent in the sequenced stages. They may be revealed by a search in the genome. The master genes themselves are controlled by various signaling pathways. Sponges have all the six signaling pathways conserved in Metazoa: Wnt, TGF-beta, Hedgehog, Notch, FGF and NO-dependent pathways. Summarizing the new data about intercellular communication in sponges, we can put forward two main questions regarding metamorphosis: (1) Which of the signaling pathways and in what hierarchical order are involved in metamorphosis? (2) How is the organization of a young sponge related to that of the larva or, in other words, is there a heredity of axes between the larva and the adult sponge?


Assuntos
Poríferos/citologia , Poríferos/crescimento & desenvolvimento , Transdução de Sinais , Animais , Transição Epitelial-Mesenquimal , Larva/citologia , Larva/crescimento & desenvolvimento , Metamorfose Biológica , Poríferos/embriologia
2.
PLoS One ; 14(2): e0212005, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30794564

RESUMO

Canonical and non-canonical Wnt signaling, as well as the Pax/Six gene network, are involved in patterning the freshwater sponge aquiferous system. Using computational approaches to identify transcription factor binding motifs in a freshwater sponge genome, we located putative PaxB binding sites near a Secreted Frizzled Related Protein (SFRP) gene in Ephydatia muelleri. EmSFRP is expressed throughout development, but with highest levels in juvenile sponges. In situ hybridization and antibody staining show EmSFRP expression throughout the pinacoderm and choanoderm in a subpopulation of amoeboid cells that may be differentiating archeocytes. Knockdown of EmSFRP leads to ectopic oscula formation during development, suggesting that EmSFRP acts as an antagonist of Wnt signaling in E. muelleri. Our findings support a hypothesis that regulation of the Wnt pathway by the Pax/Six network as well as the role of Wnt signaling in body plan morphogenesis was established before sponges diverged from the rest of the metazoans.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fatores de Transcrição Otx/metabolismo , Poríferos/crescimento & desenvolvimento , Animais , Sítios de Ligação , Padronização Corporal , Biologia Computacional , Água Doce , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Peptídeos e Proteínas de Sinalização Intracelular/química , Peptídeos e Proteínas de Sinalização Intracelular/genética , Poríferos/genética , Poríferos/metabolismo , Via de Sinalização Wnt
3.
Proc Biol Sci ; 285(1881)2018 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-29925613

RESUMO

Chancelloriids are an extinct group of spiny Cambrian animals of uncertain phylogenetic position. Despite their sponge-like body plan, their spines are unlike modern sponge spicules, but share several features with the sclerites of certain Cambrian bilaterians, notably halkieriids. However, a proposed homology of these 'coelosclerites' implies complex transitions in body plan evolution. A new species of chancelloriid, Allonnia nuda, from the lower Cambrian (Stage 3) Chengjiang Lagerstätte is distinguished by its large size and sparse spination, with modified apical sclerites surrounding an opening into the body cavity. The sclerite arrangement in A. nuda and certain other chancelloriids indicates that growth involved sclerite addition in a subapical region, thus maintaining distinct zones of body sclerites and apical sclerites. This pattern is not seen in halkieriids, but occurs in some modern calcarean sponges. With scleritome assembly consistent with a sponge affinity, and in the absence of cnidarian- or bilaterian-grade features, it is possible to interpret chancelloriids as sponges with an unusually robust outer epithelium, strict developmental control of body axis formation, distinctive spicule-like structures and, by implication, minute ostia too small to be resolved in fossils. In this light, chancelloriids may contribute to the emerging picture of high disparity among early sponges.


Assuntos
Evolução Biológica , Fósseis , Poríferos/crescimento & desenvolvimento , Animais , China , Fósseis/anatomia & histologia , Poríferos/anatomia & histologia
4.
FEMS Microbiol Ecol ; 94(5)2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29617990

RESUMO

Tedania sp. is a dominant sponge that is ubiquitous along the southeast coast of China. High-throughput sequencing and transmission electron microscopy were used to describe a detailed profile of sponge-associated microbiomes at seven life stages: adult, embryo-containing spawning adult, embryo, pre-competent larva at 2 h and 4 h, competent larva at 8 h and post-larva within 1-2h after settlement, as well as the surrounding seawater. Among a total of 15098 operational taxonomic units (OTUs), 13 were present exclusively in all stages of the sponge life cycle and could thus be identified as sponge-specific bacteria. Many OTUs were shared between the sponge and seawater, though abundance differed. The relative abundance of ß-Proteobacteria associated with sponges was much higher than found in seawater. The microbiomes from each life stage also exhibited a characteristic distribution. Synechococcales dominated in adults, and Enterobacteriaceae was prominent in larvae. The competent larva was notable, with sharp increases in the total OTUs, diversity indices, richness estimates and unique OTUs. Some bacterial groups that were rare in other sponge stages and seawater, such as Clostridia (5.6%), were markedly more abundant in competent larvae. In conclusion, this work greatly advances our understanding of the dynamics and persistence of the sponge-microbe association.


Assuntos
Bactérias/isolamento & purificação , Estágios do Ciclo de Vida , Microbiota , Poríferos/microbiologia , Animais , Bactérias/classificação , Bactérias/genética , Biodiversidade , China , DNA Bacteriano/genética , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Poríferos/crescimento & desenvolvimento , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Análise de Sequência de DNA
5.
PLoS One ; 13(3): e0194659, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29579118

RESUMO

The cold-water coral Lophelia pertusa is an ecosystem engineer that builds reef structures on the seafloor. The interaction of the reef topography with hydrodynamics is known to enhance the supply of suspended food sources to the reef communities. However, the reef framework is also a substrate for other organisms that may compete for the very same suspended food sources. Here, we used the passive suspension feeder Lophelia pertusa and the active suspension feeding sponge Hymedesmia coriacea as model organisms to study niche overlap using isotopically-enriched algae and bacteria as suspended food sources. The coral and the sponge were fed with a combination of 13C-enriched bacteria/15N-enriched algae or 15N-enriched bacteria/13C-enriched algae, which was subsequently traced into bulk tissue, coral skeleton and dissolved inorganic carbon (i.e. respiration). Both the coral and the sponge assimilated and respired the suspended bacteria and algae, indicating niche overlap between these species. The assimilation rates of C and N into bulk tissue of specimens incubated separately were not significantly different from assimilation rates during incubations with co-occurring corals and sponges. Hence, no evidence for exploitative resource competition was found, but this is likely due to the saturating experimental food concentration that was used. We do not rule out that exploitative competition occurs in nature during periods of low food concentrations. Food assimilation and respiration rates of the sponge were almost an order of magnitude higher than those of the cold-water coral. We hypothesize that the active suspension feeding mode of the sponge explains the observed differences in resource uptake as opposed to the passive suspension feeding mode of the cold-water coral. These feeding mode differences may set constraints on suitable habitats for cold-water corals and sponges in their natural habitats.


Assuntos
Antozoários/metabolismo , Poríferos/metabolismo , Ração Animal , Animais , Antozoários/química , Antozoários/crescimento & desenvolvimento , Bactérias/química , Bactérias/metabolismo , Isótopos de Carbono/química , Clorófitas/química , Clorófitas/metabolismo , Recifes de Corais , Ecossistema , Marcação por Isótopo , Isótopos de Nitrogênio/química , Poríferos/química , Poríferos/crescimento & desenvolvimento
6.
Mol Ecol ; 27(8): 2124-2137, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29473977

RESUMO

Bioeroding sponges break down calcium carbonate substratum, including coral skeleton, and their capacity for reef erosion is expected to increase in warmer and more acidic oceans. However, elevated temperature can disrupt the functionally important microbial symbionts of some sponge species, often with adverse consequences for host health. Here, we provide the first detailed description of the microbial community of the bioeroding sponge Cliona orientalis and assess how the community responds to seawater temperatures incrementally increasing from 23°C to 32°C. The microbiome, identified using 16S rRNA gene sequencing, was dominated by Alphaproteobacteria, including a single operational taxonomic unit (OTU; Rhodothalassium sp.) that represented 21% of all sequences. The "core" microbial community (taxa present in >80% of samples) included putative nitrogen fixers and ammonia oxidizers, suggesting that symbiotic nitrogen metabolism may be a key function of the C. orientalis holobiont. The C. orientalis microbiome was generally stable at temperatures up to 27°C; however, a community shift occurred at 29°C, including changes in the relative abundance and turnover of microbial OTUs. Notably, this microbial shift occurred at a lower temperature than the 32°C threshold that induced sponge bleaching, indicating that changes in the microbiome may play a role in the destabilization of the C. orientalis holobiont. C. orientalis failed to regain Symbiodinium or restore its baseline microbial community following bleaching, suggesting that the sponge has limited ability to recover from extreme thermal exposure, at least under aquarium conditions.


Assuntos
Ecologia , Microbiota/genética , Poríferos/microbiologia , Animais , Microbiota/fisiologia , Poríferos/genética , Poríferos/crescimento & desenvolvimento , Água do Mar/microbiologia , Temperatura
7.
Proc Biol Sci ; 285(1870)2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29321296

RESUMO

The ability to encrust in order to secure and maintain growth on a substrate is a key competitive innovation in benthic metazoans. Here we describe the substrate growth dynamics, mode of biomineralization and possible affinity of Namapoikia rietoogensis, a large (up to 1 m), robustly skeletal, and modular Ediacaran metazoan which encrusted the walls of synsedimentary fissures within microbial-metazoan reefs. Namapoikia formed laminar or domal morphologies with an internal structure of open tubules and transverse elements, and had a very plastic, non-deterministic growth form which could encrust both fully lithified surfaces as well as living microbial substrates, the latter via modified skeletal holdfasts. Namapoikia shows complex growth interactions and substrate competition with contemporary living microbialites and thrombolites, including the production of plate-like dissepiments in response to microbial overgrowth which served to elevate soft tissue above the microbial surface. Namapoikia could also recover from partial mortality due to microbial fouling. We infer initial skeletal growth to have propagated via the rapid formation of an organic scaffold via a basal pinacoderm prior to calcification. This is likely an ancient mode of biomineralization with similarities to the living calcified demosponge Vaceletia. Namapoikia also shows inferred skeletal growth banding which, combined with its large size, implies notable individual longevity. In sum, Namapoikia was a large, relatively long-lived Ediacaran clonal skeletal metazoan that propagated via an organic scaffold prior to calcification, enabling rapid, effective and dynamic substrate occupation and competition in cryptic reef settings. The open tubular internal structure, highly flexible, non-deterministic skeletal organization, and inferred style of biomineralization of Namapoikia places probable affinity within total-group poriferans.


Assuntos
Biomineralização , Fósseis , Poríferos/crescimento & desenvolvimento , Animais , Recifes de Corais , Fósseis/microbiologia , Fósseis/ultraestrutura , Sedimentos Geológicos , Poríferos/microbiologia , Poríferos/ultraestrutura
8.
PLoS One ; 12(8): e0182365, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28787024

RESUMO

The coral-killing sponge, Terpios hoshinota is a global invasive species that has conquered coral patches within a short span of time, which has led to a significant decline in living coral cover at various geographical locations. In this study, we surveyed the linear progression and impact of the Terpios invasion on live coral patches along Palk Bay, Indian Ocean, from August 2013 to August 2015. The field inventory revealed an extensive fatality rate of 76% as a result of Terpios outbreak. Experimental findings showed that symbiotic cyanobacteria act as a nutritional factory for the aggressive growth of Terpios. Shading hypothetically impairs the nutritional symbiont of the invasive species: the effect of sunlight on cyanobacterial biomass and its influence on Terpios progression over live coral patches was tested through in situ shading experiments. This study showed that artificial shading with cotton fabric could effectively mitigate sponge growth on live coral without affecting coral homeostasis.


Assuntos
Antozoários , Poríferos/fisiologia , Poríferos/efeitos da radiação , Luz Solar , Animais , Antozoários/crescimento & desenvolvimento , Biomassa , Cianobactérias/fisiologia , Espécies Introduzidas/estatística & dados numéricos , Modelos Lineares , Poríferos/crescimento & desenvolvimento , Poríferos/microbiologia , Simbiose , Fatores de Tempo
9.
Artigo em Inglês | MEDLINE | ID: mdl-28392375

RESUMO

Increasing prevalence of antibiotic resistance has led research to focus on discovering new antimicrobial agents derived from the marine biome. Although ample studies have investigated sponges for their bioactive metabolites with promising prospects in drug discovery, the potentiating effects of sponge extracts on antibiotics still remains to be expounded. The present study aimed to investigate the antibacterial capacity of seven tropical sponges collected from Mauritian waters and their modulatory effect in association with three conventional antibiotics namely chloramphenicol, ampicillin and tetracycline. Disc diffusion assay was used to determine the inhibition zone diameter (IZD) of the sponge total crude extracts (CE), hexane (HF), ethyl acetate (EAF) and aqueous (AF) fractions against nine standard bacterial isolates whereas broth microdilution method was used to determine their minimum inhibitory concentrations (MICs), minimum bactericidal concentrations (MBCs) and antibiotic potentiating activity of the most active sponge extract. MIC values of the sponge extracts ranged from 0.039 to 1.25mg/mL. Extracts from Neopetrosia exigua rich in beta-sitosterol and cholesterol displayed the widest activity spectrum against the 9 tested bacterial isolates whilst the best antibacterial profile was observed by its EAF particularly against Staphylococcus aureus and Bacillus cereus with MIC and MBC values of 0.039mg/mL and 0.078mg/mL, respectively. The greatest antibiotic potentiating effect was obtained with the EAF of N. exigua (MIC/2) and ampicillin combination against S. aureus. These findings suggest that the antibacterial properties of the tested marine sponge extracts may provide an alternative and complementary strategy to manage bacterial infections.


Assuntos
Antibacterianos/farmacologia , Organismos Aquáticos/química , Produtos Biológicos/farmacologia , Agonismo de Drogas , Descoberta de Drogas , Poríferos/química , Acetatos/química , Ampicilina/agonistas , Ampicilina/farmacologia , Animais , Antibacterianos/análise , Antibacterianos/química , Antibacterianos/isolamento & purificação , Organismos Aquáticos/crescimento & desenvolvimento , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Cloranfenicol/agonistas , Cloranfenicol/farmacologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Farmacorresistência Bacteriana/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Oceano Índico , Maurício , Testes de Sensibilidade Microbiana , Poríferos/crescimento & desenvolvimento , Sitosteroides/análise , Sitosteroides/isolamento & purificação , Sitosteroides/farmacologia , Solventes/química , Tetraciclina/agonistas , Tetraciclina/farmacologia
10.
J Struct Biol ; 198(3): 186-195, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28323140

RESUMO

The skeletal system of Demospongiae consists of siliceous spicules, which are composed of an axial channel containing an organic axial filament (AF) surrounded by a compact layer of hydrated amorphous silica. Here we report the ultrastructural investigations of the AF of siliceous spicules from two Demospongiae: Suberites domuncula and Tethya aurantium. Electron microscopy, electron diffraction and elemental mapping analyses on both longitudinal and transversal cross-sections yield that spicules's AF consist of a three-dimensional crystal lattice of six-fold symmetry. Its structure, which is the result of a biological growth process, is a crystalline assembly characterized by a lattice of organic cages (periodicity in the range of 6nm) filled with enzymatically-produced silica. In general, the six-fold lattice symmetry is reflected by the morphology of the AF, which is characterized by six-fold facets. This seems to be the result of a lattice energy minimization process similar to the situation found during the growth of inorganic crystals. Our structural exploitation of three-dimensional organic lattices generated by biological systems is expected to contribute for explaining the relation between axial filament's ultrastructure and spicule's ultimate morphology.


Assuntos
Poríferos/anatomia & histologia , Dióxido de Silício/química , Animais , Cristalização , Análise de Elementos Finitos , Microscopia Eletrônica , Microscopia Eletrônica de Transmissão , Morfogênese , Compostos Orgânicos/química , Poríferos/química , Poríferos/crescimento & desenvolvimento , Poríferos/ultraestrutura , Suberites/ultraestrutura
11.
Zootaxa ; 4217(1): zootaxa.4217.1.1, 2017 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-28183098

RESUMO

Sponges collected on the Guyana Shelf, predominantly in Suriname offshore waters, by Dutch HMS 'Snellius' O.C.P.S. 1966, HMS 'Luymes' O.C.P.S. II 1969, and HMS 'Luymes' Guyana Shelf 1970 expeditions are described in this study. Sponges were obtained by trawling, dredging or grabbing on sandy, muddy, shelly, and fossil reef bottoms at 88 stations between 19 and 681 m depth. A total of 351 samples were identified to species level, each consisting of one or more specimens of a given species from each individual station (together comprising 547 individuals and fragments). The collection yielded 119 species together belonging to all sponge classes, but in large majority are Demospongiae. All species are identified to species level, occasionally tentatively, and all are described and illustrated. A new subgenus is proposed, Tedania (Stylotedania) subgen. nov. and a previously synonymized genus, Tylosigma Topsent, 1894 is revived. Thirtysix species were found to be new to science, excluding the first Central West Atlantic record of the genus Halicnemia, not named at the species level because of lack of sufficient material. The new species erected are, in alphabetical order: Amphoriscus ancora sp. nov., Biemna rhabdotylostylota sp. nov., Callyspongia (Callyspongia) scutica sp. nov., Chelonaplysilla americana sp. nov., Cladocroce guyanensis sp. nov., Clathria (Axosuberites) riosae sp. nov., Clathria (Clathria) gomezae sp. nov., Clathria (Microciona) snelliusae sp. nov., Clathria (Thalysias) complanata sp. nov., Clathria (Thalysias) zeai sp. nov., Coelosphaera (Coelosphaera) lissodendoryxoides sp. nov., Craniella crustocorticata sp. nov., Diplastrella spirastrelloides sp. nov., Epipolasis tubulata sp. nov., Erylus rhabdocoronatus sp. nov., Erylus surinamensis sp. nov., Geodia pocillum sp. nov., Geodia sulcata sp. nov., Hemiasterella camelus sp. nov., Hymedesmia (Stylopus) alcoladoi sp. nov., Hymenancora cristoboi sp. nov., Penares sineastra sp. nov., Hymerhabdia kobluki sp. nov., Leucosolenia salpinx sp. nov., Petrosia (Strongylophora) devoogdae sp. nov., Placospongia ruetzleri sp. nov., Pyloderma tropicale sp. nov., Raspailia (Parasyringella) thamnopilosa sp. nov., Raspailia (Raspailia) johnhooperi sp. nov., Sphaerotylus bouryesnaultae sp. nov., Spirastrella erylicola sp. nov., Stelletta vervoorti sp. nov., Suberites crispolobatus sp. nov., Tedania (Stylotedania) folium subgen. nov. sp. nov., Timea tylasterina sp. nov., and Tylosigma ostreicola sp. nov. Two new combinations are proposed: Amphimedon nanaspiculata (Hartman, 1955) comb. nov. and Oceanapia ascidia (Schmidt, 1870) comb. nov. In addition, for two preoccupied combinations, new names, Coelosphaera (Coelosphaera) barbadensis nom. nov. and Hymedesmia (Hymedesmia) rowi nom. nov., are erected. The spatial distribution of the collected specimens over the Guyana Shelf was traced and the results were compared with existing information on bottom conditions. There was a convincing correlation between the location of fossil reefs and other hard substrates such as shell ridges with peaks in the occurrence of species diversity and specimen numbers. Stations made on sand and mud bottoms away from these zones of hard substrates were generally poor in species, but some were found to be rich in individuals of specialized soft bottom dwellers such as Tetilla pentatriaena, Tribrachium schmidtii, Fangophilina submersa, and Oceanapia species. The species composition of the Guyana Shelf was compared with that of neighbouring regions of the Caribbean and from North and East Brazil (Díaz in Miloslavich et al. 2010; Muricy et al. 2011). About 35% of the species encountered are widespread in the Central West Atlantic, occurring both to the north and to the south. Indications that the Guyana Shelf sponge fauna is clearly transitional are southernmost occurrences for Caribbean species (about 30%), and northernmost occurrences of Brazilian species (13%), with a high proportion (25%) of new species, which may be expected to have distributions extending to the Caribbean, to Brazil or both regions.


Assuntos
Poríferos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Brasil , Fósseis/anatomia & histologia , Guiana , Tamanho do Órgão , Poríferos/anatomia & histologia , Poríferos/crescimento & desenvolvimento
12.
Photochem Photobiol ; 93(1): 104-111, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27864885

RESUMO

The photolyase/cryptochrome (PHR/CRY) family is a large group of proteins with similar structure but very diverge functions such as DNA repair, circadian clock resetting and regulation of transcription. As a result of advances in the biochemistry of the CRY/PHR family and identification of new members, several adjustments have been made to the classification of this protein family. For example, a new class of PHRs, Class III, has been proposed. Furthermore, CRYs have been suggested to function as photosensory proteins in the primordial eye of sponge larvae. Additionally, a magnetosensory function has been attributed to certain CRYs. Recent advances in the field enabled us to propose a comprehensive classification scheme and nomenclatural system for this family. This review focuses on the computational and biochemical classifications of the PHR/CRY family. Several examples show that computational analysis can give a hinge about the function of newly discovered members before performing any biochemical study.


Assuntos
Criptocromos/química , Desoxirribodipirimidina Fotoliase/química , Filogenia , Animais , Ritmo Circadiano , Criptocromos/classificação , Desoxirribodipirimidina Fotoliase/classificação , Larva/crescimento & desenvolvimento , Poríferos/crescimento & desenvolvimento , Poríferos/fisiologia
13.
Artigo em Inglês | MEDLINE | ID: mdl-27994119

RESUMO

Evolving multicellularity is easy, especially in phototrophs and osmotrophs whose multicells feed like unicells. Evolving animals was much harder and unique; probably only one pathway via benthic 'zoophytes' with pelagic ciliated larvae allowed trophic continuity from phagocytic protozoa to gut-endowed animals. Choanoflagellate protozoa produced sponges. Converting sponge flask cells mediating larval settling to synaptically controlled nematocysts arguably made Cnidaria. I replace Haeckel's gastraea theory by a sponge/coelenterate/bilaterian pathway: Placozoa, hydrozoan diploblasty and ctenophores were secondary; stem anthozoan developmental mutations arguably independently generated coelomate bilateria and ctenophores. I emphasize animal origin's conceptual aspects (selective, developmental) related to feeding modes, cell structure, phylogeny of related protozoa, sequence evidence, ecology and palaeontology. Epithelia and connective tissue could evolve only by compensating for dramatically lower feeding efficiency that differentiation into non-choanocytes entails. Consequentially, larger bodies enabled filtering more water for bacterial food and harbouring photosynthetic bacteria, together adding more food than cell differentiation sacrificed. A hypothetical presponge of sessile triploblastic sheets (connective tissue sandwiched between two choanocyte epithelia) evolved oogamy through selection for larger dispersive ciliated larvae to accelerate benthic trophic competence and overgrowing protozoan competitors. Extinct Vendozoa might be elaborations of this organismal grade with choanocyte-bearing epithelia, before poriferan water channels and cnidarian gut/nematocysts/synapses evolved.This article is part of the themed issue 'Evo-devo in the genomics era, and the origins of morphological diversity'.


Assuntos
Evolução Biológica , Invertebrados/fisiologia , Neurogênese , Animais , Coanoflagelados/crescimento & desenvolvimento , Coanoflagelados/fisiologia , Evolução Molecular , Invertebrados/crescimento & desenvolvimento , Poríferos/crescimento & desenvolvimento , Poríferos/fisiologia
14.
Zootaxa ; 4208(6): zootaxa.4208.6.1, 2016 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-28006795

RESUMO

A series of recent expeditions in fjords and canals of Southern Chilean Patagonia allowed the re-collection of Halisarca magellanica Topsent, 1901 and the discovery of a new species, Halisarca desqueyrouxae sp. nov. The material studied was collected at depths ranging from 3 to 30 m at latitudes comprised between 42° and 49°S. Both species share the same habitat and show a morphological plasticity, but differ in their colour. Halisarca magellanica is bright pink to whitish with three morphs whereas H. desqueyrouxae sp. nov. is light brown to beige with two morphs. An extensive investigation in TEM and SEM reveals several differences among cell types with inclusions between both species. Three distinct spherulous cells occur. Type 1 is shared by both species, Type 2 is occasional in H. magellanica but absent from H. desqueyrouxae sp. nov. Type 3 is rare in H. magellanica and occurs abundantly in half of the specimens of H. desqueyrouxae sp. nov. Granular cells are shared by both species but do not occur in all specimens. Microgranular cells are characteristic of H. magellanica. Both species also clearly differ by their endobiotic bacteria. Phylogenetic analysis of cox1 sequences places H. magellanica as a sister group to all other previously published Halisarca species sequences (9.1-9.7% difference) except H. harmelini, while H. desqueyrouxae sp. nov. is placed as a sister group to H. dujardini (2.3% difference).


Assuntos
Poríferos/classificação , Animais , Chile , Ecossistema , Complexo IV da Cadeia de Transporte de Elétrons/genética , Larva/anatomia & histologia , Larva/classificação , Larva/genética , Larva/crescimento & desenvolvimento , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Filogenia , Poríferos/anatomia & histologia , Poríferos/genética , Poríferos/crescimento & desenvolvimento , Análise de Sequência de DNA
15.
Zootaxa ; 4168(3): 512-524, 2016 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-27701324

RESUMO

In this study, we describe a new species of cladorhizid sponge, which shows a very peculiar mode of life: It always occurs in association with the scleractinian cold-water corals Lophelia pertusa and Madrepora oculata. Although the sponge lives in nutrient-rich areas, we document its carnivorous feeding behavior. The identity of the new species was verified using molecular markers: the species is very closely related to the North-Atlantic Cladorhiza abyssicola, but it differs distinctly, and forms a monophyletic clade. The two species might be considered very close relatives, probably sister species deriving from a common ancestor.


Assuntos
Antozoários/parasitologia , Poríferos/classificação , Poríferos/fisiologia , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Carnivoridade/classificação , Carnivoridade/fisiologia , Ecossistema , Tamanho do Órgão , Poríferos/anatomia & histologia , Poríferos/crescimento & desenvolvimento , Comportamento Predatório
16.
Zootaxa ; 4158(1): 105-16, 2016 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-27615873

RESUMO

Alveospongia sinuosclera gen. nov. sp. nov. is described from shallow-waters off Canavieiras (Bahia, Brazil). The species bears an unusual morphology, combining saccular or alveolar, evenly perforated habit, and sinuous spiny microrhabdose microscleres. This sponge is tentatively classified within the Heteroxyidae Dendy (1905), on the basis of its confused choanosomal architecture of styles, and possession of spiny microrhabdose microscleres. Assays to generate DNA sequences from this material were unsuccessful. We emended the diagnosis of the family to include species bearing saccular/alveolar shape, microrhabdose acanthomicrostrongyles and styles/strongyles with modifications at the ends. The proposed new genus is compared to the remaining heteroxyid genera, as well as Crella (Crellidae), Batzella (Chondropsidae), Goreauiella (Astroscleridae) and Sceptrintus (Podospongiidae). A revised key for identification of Heteroxyidae genera is provided.


Assuntos
Poríferos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Brasil , Tamanho do Órgão , Poríferos/anatomia & histologia , Poríferos/crescimento & desenvolvimento
17.
Zootaxa ; 4103(3): 230-8, 2016 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-27394730

RESUMO

Guancha tetela was originally described as a species having a peduncle and a skeleton exclusively composed of sagittal triactines. Therefore, according to the most recent phylogeny of Clathrinida, it should be placed in the genus Clathrina. This species was collected on the Northeastern Brazilian coast in 1968 and it was not collected again until 2011 in Curaçao. In this study, we reanalyzed the type material and the new specimens from Curaçao under a morphological-molecular approach. Morphological analysis revealed the presence of tetractines in the skeleton of all the studied specimens, including a slide of the holotype. In the molecular phylogeny G. tetela grouped with genera containing tetractines, but as an independent new lineage, different from all the other genera of Clathrinida. Based on these results, we propose the erection of a new genus, Nicola gen. nov., to include species whose body is composed of tubes without anastomosis nor branches but that run in parallel and coalesce at the apical and basal regions. Moreover, the skeleton is exclusively composed of sagittal triactines and tetractines.


Assuntos
Poríferos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Brasil , Tamanho do Órgão , Filogenia , Poríferos/anatomia & histologia , Poríferos/genética , Poríferos/crescimento & desenvolvimento
18.
Zootaxa ; 4114(3): 331-40, 2016 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-27395134

RESUMO

The genus Neopetrosia was characterized by has fine brushes of oxeas issued from subectosomal tracts and compact choanosomal network. We report and describe here specimens collected in the coast of Brazil: Neopetrosia sulcata sp. nov. and Neopetrosia proxima. The first was previously recorded from Brazil as Neopetrosia proxima, but it was found that these specimens corresponded to a new species. Thus, we provide here the characterization of N. proxima from Brazilian coast. A taxonomic study of Brazilian samples is given, including description, illustrations and geographic distribution, combined with the comparison of the new species with all other descriptions of Neopetrosia from Atlantic.


Assuntos
Poríferos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Brasil , Ecossistema , Tamanho do Órgão , Poríferos/anatomia & histologia , Poríferos/crescimento & desenvolvimento
19.
Zootaxa ; 4114(4): 393-408, 2016 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-27395137

RESUMO

Although there is a long history of taxonomic investigation in Caribbean sponges, there are still many undescribed species. Furthermore, field observations and corroborating morphological analyses are revealing that what was believed to be single, somewhat variable species, may consist of two or more species, often easier to distinguish once well characterized. This is the case for Dragmacidon reticulatum (Ridley & Dendy, 1886) (Porifera, Demospongiae, Axinellida, Axinellidae), a rather well-known sponge, with an ample distribution and presence in rocky and reef environments of the tropical and subtropical Western Atlantic, with local records in the majority of the countries of the area, from Bermuda to Brazil. Field observations and a detailed review of material from different areas, including some type specimens, led us to the distinction of two different species in terms of external morphology, size of spicules, and skeletal architecture. The distinction was confirmed in the Bahamas and Santa Marta, Colombia, where the two species coexist. One of the species is Dragmacidon reticulatum sensu stricto, but for the other there is need to erect a new name, for which we propose Dragmacidon alvarezae n. sp. The purpose of the present work is to describe, illustrate and compare these two species.


Assuntos
Poríferos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Bahamas , Tamanho Corporal , Brasil , Ecossistema , Tamanho do Órgão , Poríferos/anatomia & histologia , Poríferos/crescimento & desenvolvimento
20.
Zootaxa ; 4121(1): 1-48, 2016 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-27395201

RESUMO

Extensive new collections of latrunculid sponges from British Columbia, the Aleutian Islands, and the Gulf of Alaska, have extended the distributions of known species Latrunculia oparinae Samaai & Krasokhin, 2002, from the Russian Sea of Okhotsk, L. velera Lehnert et al., 2006, from the Aleutian Islands, and L. austini Samaai et al., 2006, from British Columbia. New material has facilitated detailed re-descriptions of these species and in situ images have improved our understanding of their living morphology and ecology. Several new species of Latrunculia were discovered within these collections: sympatric species Latrunculia hamanni sp. nov. and L. oparinae are described here and differentiated from each other by various field characteristics, and L. lincfreesei sp. nov. is described from the Gulf of Alaska. In terms of their higher systematics, L. austini and L. hamanni sp. nov. are recognisable within the subgenus Latrunculia du Bocage, 1869, and L. lincfreesei sp. nov. in subgenus Biannulata Samaai et al., 2006. A third subgenus, Uniannulata subgen. nov., is proposed for L. oparinae, L. velera and several fossil species in southern New Zealand and Western Australian Eocene fossiliferous sediments. In all of these species the subsidiary whorl, apical whorl, and apex of the anisodiscorhabd are fused. Living species of Uniannulata subgen. nov. are thus far restricted to the North Pacific Ocean. A new genus, Bomba gen. nov., is proposed for a rare latrunculid species, Bomba endeavourensis gen. et sp. nov., discovered in deep waters on British Columbia's Endeavour Ridge. Finally, Latrunclava gen. nov. is proposed for species with long, sceptre-like anisoconicorhabds in addition to the typical, smaller anisodiscorhabds; Latrunclava imago gen. et sp. nov. is described from the central Aleutian Islands.


Assuntos
Poríferos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Austrália , Tamanho Corporal , Ecossistema , Fósseis/anatomia & histologia , Nova Zelândia , Tamanho do Órgão , Poríferos/anatomia & histologia , Poríferos/crescimento & desenvolvimento
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