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1.
Microb Pathog ; 162: 105370, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34954045

RESUMO

Although species of the genus Ceratomyxa Thélohan, 1892 mostly parasitize marine fish around the world, a surprising diversity of the genus has recently been reported from Amazonian freshwater fish. In this study, we report a freshwater Ceratomyxa species parasitizing Hemiodus orthonops (Hemiodontidae) from the Paraná River (La Plata Basin) in a watershed flowing into the southern part of South America, which expands the geographic distribution of this fish parasite in the freshwater resources of the continent. We applied a combination of morphological, small subunit ribosomal DNA (SSU rDNA), and phylogenetic analyses, and vermiform-shaped plasmodia endowed with motility were found swimming in the bile of the fish. The characteristics of the plasmodia and myxospores of the Ceratomyxa species found in the Paraná River resembled those of Ceratomyxa fonsecai, a parasite of the congeneric host Hemiodus unimaculatus from the Tocantins River basin in northern Brazil. Due to the close morphological and morphometric resemblances and the impossibility of genetic comparison, the parasite found in H. orthonops from the Paraná River was designated as Ceratomyxa cf. fonsecai, and the definition of its taxonomic status was left for further study. Maximum likelihood and Bayesian analyses showed Ceratomyxa cf. fonsecai clustering within a well-supported clade, together with other Amazonian freshwater ceratomyxids. The present study suggests that shifts of the complex host/parasite between marine and freshwater environments were facilitated by marine incursions into South America in the Early Miocene.


Assuntos
Caraciformes , Cnidários , Doenças dos Peixes , Myxozoa , Parasitos , Doenças Parasitárias em Animais , Animais , Teorema de Bayes , Brasil , Cnidários/genética , DNA Ribossômico/genética , Água Doce , Vesícula Biliar , Myxozoa/genética , Filogenia
2.
Sci Total Environ ; 803: 149923, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34487898

RESUMO

While it is often assumed that oncogenic processes in metazoans can influence species interactions, empirical evidence is lacking. Here, we use the cnidarian Hydra oligactis to experimentally explore the consequences of tumor associated phenotypic alterations for its predation ability, relationship with commensal ciliates and vulnerability to predators. Unexpectedly, hydra's predation ability was higher in tumorous polyps compared to non-tumorous ones. Commensal ciliates colonized preferentially tumorous hydras than non-tumorous ones, and had a higher replication rate on the former. Finally, in a choice experiment, tumorous hydras were preferentially eaten by a fish predator. This study, for the first time, provides evidence that neoplastic growth has the potential, through effect(s) on host phenotype, to alter biotic interactions within ecosystems and should thus be taken into account by ecologists.


Assuntos
Cnidários , Hydra , Neoplasias , Animais , Ecossistema , Água Doce
3.
Zootaxa ; 5067(3): 429-438, 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34810734

RESUMO

Members of the class Myxosporea Btschli, 1881 have a cosmopolitan distribution in a wide variety of fish species worldwide. In the present study, the black scorpionfish Scorpaena porcus collected from the Sinop coasts of the Black Sea was investigated for myxosporean parasites using both conventional and molecular methods in the period between September 2015 and August 2019. Using morphological and morphometric data, the myxosporean parasite Ceratomyxa scorpaeni Garbouj, Rangel, Castro, Hmissi, Santos, Bahri, 2016 was identified in the gall bladder of host fish. Molecular analysis of the 18S rDNA gene confirmed the identity of this parasite as C. scorpaeni. This is the first report of its occurrence in the Black Sea.


Assuntos
Cnidários , Doenças dos Peixes , Myxozoa , Doenças Parasitárias em Animais , Animais , Mar Negro , Myxozoa/genética , Filogenia
4.
Zootaxa ; 5039(2): 151-178, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34811089

RESUMO

A compilation of the ciliate epibiont species (Ciliophora) found on marine and fresh water cnidarians has been carried out based on published records. The checklist includes the taxonomic position of each species of epibiontic ciliate, the species of basibiont cnidarians, the geographic zones and the bibliographic references where they were recorded. Cnidarians, especially colonial sessile forms, represent suitable substrates for numerous sessile and vagile ciliates. Altogether 79 ciliate species belong to five classes viz. Spirotrichea, Heterotrichea, Phyllopharingea, Suctorea and Oligohymenophorea were listed. The most diverce as epibions on cnidarians are representatives of Suctorea with 41 species and Peritrichia (under the class Oligohymenophorea) with 25 species. Three species belong to class Spirotrichea, four Heterotrichea and one Phyllopharingea. Among the other representatives (except Peritrichia) of class Oligohymenophorea, four species belong to subclass Scutucociliatia, one species each in subclass Hymenostomatia and Apostomatia. One suctorian species Ophryodendron abietinum and two species of peritrichs, Cothurnia cordylophora and Rhabdostyla sertularium one Heterotrichea Halofolliculina corallasia and one Scutucociliatia Philaster guamensis are likely specific to cnidarian hosts only.


Assuntos
Cilióforos , Cnidários , Oligoimenóforos , Animais , Água Doce
5.
Front Immunol ; 12: 689463, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34248980

RESUMO

Pattern recognition receptors (PRRs) are evolutionarily ancient and crucial components of innate immunity, recognizing danger-associated molecular patterns (DAMPs) and activating host defenses. Basal non-bilaterian animals such as cnidarians must rely solely on innate immunity to defend themselves from pathogens. By investigating cnidarian PRR repertoires we can gain insight into the evolution of innate immunity in these basal animals. Here we utilize the increasing amount of available genomic resources within Cnidaria to survey the PRR repertoires and downstream immune pathway completeness within 15 cnidarian species spanning two major cnidarian clades, Anthozoa and Medusozoa. Overall, we find that anthozoans possess prototypical PRRs, while medusozoans appear to lack these immune proteins. Additionally, anthozoans consistently had higher numbers of PRRs across all four classes relative to medusozoans, a trend largely driven by expansions in NOD-like receptors and C-type lectins. Symbiotic, sessile, and colonial cnidarians also have expanded PRR repertoires relative to their non-symbiotic, mobile, and solitary counterparts. Interestingly, cnidarians seem to lack key components of mammalian innate immune pathways, though similar to PRR numbers, anthozoans possess more complete immune pathways than medusozoans. Together, our data indicate that anthozoans have greater immune specificity than medusozoans, which we hypothesize to be due to life history traits common within Anthozoa. Overall, this investigation reveals important insights into the evolution of innate immune proteins within these basal animals.


Assuntos
Cnidários/metabolismo , Evolução Molecular , Imunidade Inata , Traços de História de Vida , Proteoma , Receptores de Reconhecimento de Padrão/metabolismo , Animais , Antozoários/genética , Antozoários/imunologia , Antozoários/metabolismo , Cnidários/genética , Cnidários/imunologia , Bases de Dados Genéticas , Filogenia , Proteômica , Receptores de Reconhecimento de Padrão/genética , Especificidade da Espécie
6.
Braz J Biol ; 82: e242823, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34133567

RESUMO

Myxosporidiosis is an infectious disease caused by myxozoans of the Phylum Cnidaria, Class Myxosporea, and Order Bivalvulida, considered a common parasite in fresh and saltwater fishes that parasitize many organs, especially gills. In the present study, 49 specimens of fishes belonging to eight genera: Tetragonopterus, Leporinus, Myleus, Pirinampus, Rhapiodon, Pygocentrus, Ageneiosus, and Serrasalmus were collected and blood smears were made, fixed with absolute methanol, and stained with Giemsa 10% to survey hemoparasites. However, myxospores were found in the circulating blood of five (10.20%) fishes belonging to genus Tetragonopterus, Myleus, and Pygocentrus. Two morphological types of Myxobolus spp. were identified in all the five fish specimens analyzed. Usually, investigations on myxozoans in fish are carried out with the search for plasmodia or cysts in the fish organs and observation of the cavity of organs. Nevertheless, this study highlights the importance of also examining the blood of these animals, since these parasites can cause severe pathogenic diseases in fish. Thus, the blood analyses can proportionate preventive sanitary control for commercial fish avoiding economic loss.


Assuntos
Cnidários , Doenças dos Peixes , Myxobolus , Myxozoa , Doenças Parasitárias em Animais , Animais , Brasil , Peixes , Brânquias , Humanos , Filogenia
7.
ACS Chem Biol ; 16(8): 1538-1545, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34181382

RESUMO

The stabilities of Ca2+-regulated ctenophore and coelenterate apo-photoproteins, apo-mnemiopsin (apo-Mne) and apo-aequorin (apo-Aeq), respectively, were compared biochemically, biophysically, and structurally. Despite high degrees of structural and functional conservation, drastic variations in stability and structural dynamics were found between the two proteins. Irreversible thermoinactivation experiments were performed upon incubation of apo-photoproteins at representative temperatures. The inactivation rate constants (kinact) at 50 °C were determined to be 0.001 and 0.004 min-1 for apo-Mne and apo-Aeq, respectively. Detailed analysis of the inactivation process suggests that the higher thermostability of apo-Mne is due to the higher activation energy (Ea) and subsequently higher values of ΔH* and ΔG* at a given temperature. According to molecular dynamics simulation studies, the higher hydrogen bond, electrostatic, and van der Waals energies in apo-Mne can validate the relationship between the thermal adaptation of apo-Mne and the energy barrier for the inactivation process. Our results show that favorable residues for protein thermostability such as hydrophobic, charged, and adopted α-helical structure residues are more frequent in the apo-Mne structure. Although the effect of acrylamide on fluorescence quenching suggests that the local flexibility in regions around Trp and Tyr residues of apo-Aeq is higher than that of apo-Mne, which results in it having a better ability to penetrate acrylamide molecules, the root-mean-square fluctuation of helix A in apo-Mne is higher than that in apo-Aeq. It seems that the greater flexibility of apo-Mne in these regions may be considered as a determining factor, affecting the thermal stability of apo-Mne through a balance between structural rigidity and flexibility.


Assuntos
Cnidários/química , Ctenóforos/química , Proteínas Luminescentes/química , Estabilidade Proteica , Animais , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Cinética , Simulação de Dinâmica Molecular , Maleabilidade , Conformação Proteica , Termodinâmica
8.
Microbiome ; 9(1): 127, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-34078452

RESUMO

BACKGROUND: Marine holobionts depend on microbial members for health and nutrient cycling. This is particularly evident in cnidarian-algae symbioses that facilitate energy and nutrient acquisition. However, this partnership is highly sensitive to environmental change-including eutrophication-that causes dysbiosis and contributes to global coral reef decline. Yet, some holobionts exhibit resistance to dysbiosis in eutrophic environments, including the obligate photosymbiotic scyphomedusa Cassiopea xamachana. METHODS: Our aim was to assess the mechanisms in C. xamachana that stabilize symbiotic relationships. We combined labelled bicarbonate (13C) and nitrate (15N) with metabarcoding approaches to evaluate nutrient cycling and microbial community composition in symbiotic and aposymbiotic medusae. RESULTS: C-fixation and cycling by algal Symbiodiniaceae was essential for C. xamachana as even at high heterotrophic feeding rates aposymbiotic medusae continuously lost weight. Heterotrophically acquired C and N were readily shared among host and algae. This was in sharp contrast to nitrate assimilation by Symbiodiniaceae, which appeared to be strongly restricted. Instead, the bacterial microbiome seemed to play a major role in the holobiont's DIN assimilation as uptake rates showed a significant positive relationship with phylogenetic diversity of medusa-associated bacteria. This is corroborated by inferred functional capacity that links the dominant bacterial taxa (~90 %) to nitrogen cycling. Observed bacterial community structure differed between apo- and symbiotic C. xamachana putatively highlighting enrichment of ammonium oxidizers and nitrite reducers and depletion of nitrogen-fixers in symbiotic medusae. CONCLUSION: Host, algal symbionts, and bacterial associates contribute to regulated nutrient assimilation and cycling in C. xamachana. We found that the bacterial microbiome of symbiotic medusae was seemingly structured to increase DIN removal and enforce algal N-limitation-a mechanism that would help to stabilize the host-algae relationship even under eutrophic conditions. Video abstract.


Assuntos
Antozoários , Cnidários , Dinoflagelados , Animais , Eutrofização , Nitrogênio , Filogenia , Simbiose
9.
An Acad Bras Cienc ; 93(2): e20190574, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34076086

RESUMO

Ephyrae are the young scyphozoan jellyfishes that usually passes unnoticed, whereas their adult counterparts play major ecological roles and can negatively affect economic activities when they occur in high densities. We describe, for the first time, wild ephyrae of Lychnorhiza lucerna (Scyphozoa, Rhizostomeae) from the Patos Lagoon Estuary, Southern Brazil. A total of 10 ephyrae were found in salinities between 12 and 33 and temperatures between 16 and 27°C. The presence of digitata, eight oral arms and serrated tips on marginal lobes allowed species determination. Wild ephyrae were morphologically identical to laboratory-cultivated individuals. The youngest individual was about one to two days old, and the most developed one, between 12 and 14 days old. Recruitment of L. lucerna probably initiated during warmer months (December until February) because nine out of ten individuals were found in high temperature (> 20° C) and salinity (> 30) waters. On the other hand, a mid-winter occurrence of a single ephyra (T=16° C, S= 12) demonstrates that the species may support a considerable range of variation in the physical environment. We reinforce the importance of long-term studies to provide information about the species coupling with seasonal cycles and the dynamics of estuarine and coastal areas.


Assuntos
Cnidários , Cifozoários , Adulto , Animais , Brasil , Humanos , Salinidade , Temperatura
10.
Genes (Basel) ; 12(5)2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-34067753

RESUMO

Medusozoans, the Cnidarian subphylum, have multiple life stages including sessile polyps and free-swimming medusae or jellyfish, which are typically bell-shaped gelatinous zooplanktons that exhibit diverse morphologies. Despite having a relatively complex body structure with well-developed muscles and nervous systems, the adult medusa stage maintains a high regenerative ability that enables organ regeneration as well as whole body reconstitution from the part of the body. This remarkable regeneration potential of jellyfish has long been acknowledged in different species; however, recent studies have begun dissecting the exact processes underpinning regeneration events. In this article, we introduce the current understanding of regeneration mechanisms in medusae, particularly focusing on cellular behaviors during regeneration such as wound healing, blastema formation by stem/progenitor cells or cell fate plasticity, and the organism-level patterning that restores radial symmetry. We also discuss putative molecular mechanisms involved in regeneration processes and introduce a variety of novel model jellyfish species in the effort to understand common principles and diverse mechanisms underlying the regeneration of complex organs and the entire body.


Assuntos
Cnidários/fisiologia , Regeneração , Células-Tronco/citologia , Animais , Padronização Corporal , Diferenciação Celular , Cnidários/citologia , Cnidários/crescimento & desenvolvimento
11.
Sci Rep ; 11(1): 9834, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33972594

RESUMO

The cytochrome P450 (CYP) superfamily is a diverse and important enzyme family, playing a central role in chemical defense and in synthesis and metabolism of major biological signaling molecules. The CYPomes of four cnidarian genomes (Hydra vulgaris, Acropora digitifera, Aurelia aurita, Nematostella vectensis) were annotated; phylogenetic analyses determined the evolutionary relationships amongst the sequences and with existing metazoan CYPs. 155 functional CYPs were identified and 90 fragments. Genes were from 24 new CYP families and several new subfamilies; genes were in 9 of the 12 established metazoan CYP clans. All species had large expansions of clan 2 diversity, with H. vulgaris having reduced diversity for both clan 3 and mitochondrial clan. We identified potential candidates for xenobiotic metabolism and steroidogenesis. That each genome contained multiple, novel CYP families may reflect the large evolutionary distance within the cnidarians, unique physiology in the cnidarian classes, and/or different ecology of the individual species.


Assuntos
Evolução Biológica , Cnidários/genética , Sistema Enzimático do Citocromo P-450/genética , Família Multigênica , Animais , Cnidários/enzimologia , Sistema Enzimático do Citocromo P-450/metabolismo , Genoma , Filogenia , Xenobióticos/metabolismo
12.
Toxicon ; 196: 25-31, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33798604

RESUMO

An epidemiological study on animal poisoning due to plants and zootoxins has been carried out by the Poison Control Centre of Milan (CAV) in collaboration with the University of Milan (Italy). During the period January 2015-March 2019, the CAV received 932 calls on animal poisonings, 12.66% (n = 118) of which were related to plants and zootoxins. Among these, 95 enquiries (80.51%) concerned exposures to plants and 23 (19.49%) to zootoxins. The dog was the species most frequently involved (67.80% of the calls, n = 80), followed by the cat (26.27%, n = 31). As for the plants, several poisoning episodes were related to glycoside-, alkaloid-, oxalate- and diterpenoid-containing species. Cycas revoluta, Euphorbia pulcherrima and Hydrangea macrophylla were the most often reported plants. The outcome has been reported for half of the episodes (51.58%, n = 49) and it was fatal for 3 animals (6.12%). Regarding the zootoxins, the majority of the enquiries were related to asp viper (Vipera aspis), but exposures to pine processionary moth (Thaumetopoea pityocampa), common toad (Bufo), fire salamander (Salamandra), and jellyfish (phylum Cnidaria) were also reported. The outcome was known in 65.22% of the cases with just one fatal episode. This epidemiological investigation depicts an interesting overview on the issue of plant and zootoxin exposures in domestic animals, highlighting the relevance of these agents as causes of animal poisoning and providing useful information for prevention and diagnosis.


Assuntos
Animais Domésticos , Envenenamento/veterinária , Animais , Gatos , Cnidários , Cycas , Cães , Itália/epidemiologia , Centros de Controle de Intoxicações
13.
Zootaxa ; 4933(2): zootaxa.4933.2.5, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33756798

RESUMO

A new species of the cosmopolitan jellyfish genus Aurelia is described from the coastal waters of Mozambique using a combination of morphological, meristic and genetic information (COI and 18S). The species can be separated from congeners that have been recently described by a combination of bell shape, number of canal origins and anastomoses, and the shape of the manubrium and oral arms. Three types of nematocysts are present in the tissues of both the bell margin and oral arms, and this description of the cnidome will allow for future comparison. Pairwise genetic comparisons showed a mean COI divergence of 4.8% within the group, and a mean divergence ranging between 15% and 22% with all other species of Aurelia.


Assuntos
Cnidários , Cifozoários , Animais , Moçambique , Nematocisto
14.
Dis Aquat Organ ; 144: 41-54, 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33704091

RESUMO

We identified Myxobolus anatolicus Pekmezci, Yardimci, Yilmaz & Polat, 2014 and 4 novel Myxobolus species from the Anatolian khramulya Capoeta tinca (Cyprinidae) in northern Turkey based on morphology, histology, and phylogenetic analysis. M. karaeri sp. nov. plasmodia were observed in the skin doublets between fin rays, the surfaces of the operculum, the gill arch membrane, and in the skin of the fin base. M. samsunensis sp. nov. plasmodia were observed in epithelial tissue inside and on the surface and midline of the gill filaments. M. cakmaki sp. nov. presented as a typical vascular species, which develops in large plasmodia at the end of the gill filaments. The chondrophilic M. ekingeni sp. nov. was detected by histology inside the cartilaginous gill arch and the cartilaginous gill rays of the filaments. Phylogenetic analysis of small subunit ribosomal DNA sequences revealed that M. karaeri sp. nov. and M. samsunensis sp. nov. were clustered with Myxobolus species that infect gills, scales, and fins of cyprinids. M. cakmaki sp. nov. grouped with Myxobolus species that exclusively infect the gills of cyprinids. No molecular data were available for M. ekingeni sp. nov.


Assuntos
Cnidários , Cyprinidae , Doenças dos Peixes , Myxobolus , Myxozoa , Doenças Parasitárias em Animais , Animais , DNA Ribossômico , Doenças dos Peixes/epidemiologia , Brânquias , Myxobolus/genética , Myxozoa/genética , Filogenia , Turquia
15.
Toxicon ; 195: 93-103, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33741399

RESUMO

The jellyfish venom stored in nematocysts contains highly toxic compounds comprising of polypeptides, enzymes and other proteins, which form their chemical defence armoury against predators. We have characterized the proteome of crude venom extract from three bloom-forming scyphozoan jellyfish along the south-west coast of India, Chrysaora caliparea, Cyanea nozakii and Lychnorhiza malayensis using a Quadrupole-Time of Flight (Q/TOF) mass spectrometry analysis. The most abundant toxin identified from Chrysaora caliparea and Lychnorhiza malayensis is similar to the pore-forming toxins and metalloproteinases. A protective antioxidant enzyme called peroxiredoxin was found abundantly in Cyanea nozakii. Metalloproteinase identified from the C. caliparea shows similarity with the venom of pit viper (Bothrops pauloensis), while that of L. malayensis was similar to the venom of snakes such as the Bothrops insularis and Bothrops asper. Kininogen-1 is a secreted protein, identified for the first time from the jellyfish L. malayensis. The proteome analysis of Cyanea nozakii, Chrysaora caliparea and Lychnorhiza malayensis contained 20, 12, 8 unique proteins, respectively. Our study characterized the proteome map of crude venom extract from L. malayensis and C. caliparea for the first time, and the venom profile is compared with published information elsewhere. Proteomic data from this study has been made available in the public domain.


Assuntos
Cnidários , Venenos de Cnidários , Proteoma/metabolismo , Cifozoários , Animais , Índia , Proteômica
16.
Proc Biol Sci ; 288(1944): 20202939, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33529559

RESUMO

Primitive cnidarians are crucial for elucidating the early evolution of metazoan body plans and life histories in the late Neoproterozoic and Palaeozoic. The highest complexity of both evolutionary aspects within cnidarians is found in extant hydrozoans. Many colonial hydrozoans coated with chitinous exoskeletons have the potential to form fossils; however, only a few fossils possibly representing hydroids have been reported, which still require scrutiny. Here, we present an exceptionally well-preserved hydroid found in the Upper Cambrian Fengshan Formation in northern China. It was originally interpreted as a problematic graptolite with an uncertain systematic position. Based on three characteristic morphological traits shared with extant hydroids (with paired hydrothecae, regular hydrocaulus internodes and special intrathecal origin pattern of hydrocladium), we propose this fossil hydroid as a new genus, Palaeodiphasia gen. nov., affiliated with the advanced monophyletic hydrozoan clade Macrocolonia typically showing loss of the medusa stage. More Macrocolonia fossils reviewed here indicate that this life strategy of medusa loss has been achieved already as early as the Middle Devonian. The early stratigraphical appearance of such advanced hydroid contrasts with previous molecular hypotheses regarding the timing of medusozoan evolution, and may be indicative for understanding the Ediacaran cnidarian radiation.


Assuntos
Cnidários , Hidrozoários , Animais , Evolução Biológica , China , Fósseis , Hidrozoários/genética , Filogenia
17.
Nat Prod Rep ; 38(2): 362-413, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33570537

RESUMO

This review covers the literature published in 2019 for marine natural products (MNPs), with 719 citations (701 for the period January to December 2019) referring to compounds isolated from marine microorganisms and phytoplankton, green, brown and red algae, sponges, cnidarians, bryozoans, molluscs, tunicates, echinoderms, mangroves and other intertidal plants and microorganisms. The emphasis is on new compounds (1490 in 440 papers for 2019), together with the relevant biological activities, source organisms and country of origin. Pertinent reviews, biosynthetic studies, first syntheses, and syntheses that led to the revision of structures or stereochemistries, have been included. Methods used to study marine fungi and their chemical diversity have also been discussed.


Assuntos
Organismos Aquáticos/química , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Animais , Bactérias/química , Briozoários/química , Cnidários/química , Equinodermos/química , Fungos/química , Estrutura Molecular , Moluscos/química , Fitoplâncton/química , Rodófitas/química , Urocordados/química , Áreas Alagadas
18.
Philos Trans R Soc Lond B Biol Sci ; 376(1821): 20190764, 2021 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-33550954

RESUMO

Discussions of the function of early nervous systems usually focus on a causal flow from sensors to effectors, by which an animal coordinates its actions with exogenous changes in its environment. We propose, instead, that much early sensing was reafferent; it was responsive to the consequences of the animal's own actions. We distinguish two general categories of reafference-translocational and deformational-and use these to survey the distribution of several often-neglected forms of sensing, including gravity sensing, flow sensing and proprioception. We discuss sensing of these kinds in sponges, ctenophores, placozoans, cnidarians and bilaterians. Reafference is ubiquitous, as ongoing action, especially whole-body motility, will almost inevitably influence the senses. Corollary discharge-a pathway or circuit by which an animal tracks its own actions and their reafferent consequences-is not a necessary feature of reafferent sensing but a later-evolving mechanism. We also argue for the importance of reafferent sensing to the evolution of the body-self, a form of organization that enables an animal to sense and act as a single unit. This article is part of the theme issue 'Basal cognition: multicellularity, neurons and the cognitive lens'.


Assuntos
Vias Eferentes/fisiologia , Fenômenos Fisiológicos do Sistema Nervoso , Propriocepção , Animais , Cnidários/fisiologia , Ctenóforos/fisiologia , Sistema Nervoso/química , Placozoa/fisiologia , Poríferos/fisiologia
19.
PLoS One ; 16(1): e0244202, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33434218

RESUMO

A common transcriptome assembly error is to mistake different transcripts of the same gene as transcripts from multiple closely related genes. This error is difficult to identify during assembly, but in a phylogenetic analysis such errors can be diagnosed from gene phylogenies where they appear as clades of tips from the same species with improbably short branch lengths. treeinform is a method that uses phylogenetic information across species to refine transcriptome assemblies within species. It identifies transcripts of the same gene that were incorrectly assigned to multiple genes and reassign them as transcripts of the same gene. The treeinform method is implemented in Agalma, available at https://bitbucket.org/caseywdunn/agalma, and the general approach is relevant in a variety of other contexts.


Assuntos
Transcriptoma , Interface Usuário-Computador , Algoritmos , Animais , Análise por Conglomerados , Cnidários/classificação , Cnidários/genética , Modelos Teóricos , Filogenia
20.
Microb Pathog ; 150: 104718, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33385492

RESUMO

A new cnidarian myxosporean infecting the spleen of an economic and ecological important bryconid fish (Salminus franciscanus) is described based on integrative taxonomic approach including morphological, ultrastructural, biological traits, geography, molecular data and phylogenetic analysis. In a total of thirty specimens examined, nineteen (63.3%) were infected by an undescribed parasite species belonging to the genus Myxobolus. Plasmodial development was asynchronous, with young development in the periphery and mature myxospores in the central area and without projections and microvilli in the plasmodial wall. Mature myxospores were ovoid in shape and measured 7.9 ± 0.2 µm (7.6-8.1 µm) in length and 5.4 ± 0.1 µm (5.0-5.6 µm) in width. The two polar capsules were equal in size, occupying a little more than half of the myxospore body, measuring 4.0 ± 0.2 µm (3.9-4.1 µm) in length and 1.7 ± 0.1 µm (1.5-1.8 µm) in width. The polar tubules coiled in six turns, perpendicular to the long axis of polar capsule. Phylogenetic analysis placed the new species within a clade containing nine myxobolid species from South American characiforms fish and appears as a close species of Myxobolus pantanalis. Nevertheless, the sequences of the new species and M. pantanalis have a large genetic divergence of 13.5% in their SSU rDNA. In light of the differences observed from the integrative taxonomy, we confidently considered that this isolate is a new species of cnidarian myxosporean, M. douradae n. sp., increasing the knowledge of diversity of this enigmatic group of cnidarians.


Assuntos
Cnidários , Doenças dos Peixes , Doenças Parasitárias em Animais , Animais , Brasil , Brânquias , Filogenia , Baço
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