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1.
Zoolog Sci ; 38(4): 352-358, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34342956

RESUMO

A new species of brittle star, Ophiodelos okayoshitakai, is described from two specimens collected in Sagami Bay, central-eastern Japan. Photographic examination of the holotype specimen of the sole other congener, Ophiodelos insignis Koehler, 1930, indicates that Ophiodelos okayoshitakai sp. nov. is distinguished from O. insignis by i) the disc stumps covering on the dorsal side of the disc, ii) the dorsal and ventral arm plates being separated from each other on the proximal arm regions, iii) the dorsal arm plate being smooth, iv) the arm spines at proximal portion of the arm being six in number and smooth in shape, and v) the number and shape of the tentacle scales at proximal portion of the arm being up to two and spine-shaped adradially and oval abradially. Detailed morphological observations of this new species suggest the inclusion of Ophiodelos, whose familial affiliation remains unclear, in the suborder Ophiacanthina. More than 10 juveniles of various sizes were found in the disc of Ophiodelos okayoshitakai sp. nov., indicating a brooding reproduction. This is the first report of the genus Ophiodelos from Japanese waters. We also provided a nucleotide sequence for part of the cytochrome c oxidase subunit I (COI) gene in O. okayoshitakai sp. nov. for future studies of DNA barcoding and phylogeny.


Assuntos
Equinodermos/fisiologia , Reprodução/fisiologia , Animais , Japão , Oceano Pacífico
2.
Zoolog Sci ; 38(3): 203-212, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34057344

RESUMO

In bryozoans (phylum Bryozoa), representative colonial animals mostly found in marine environments, some species possess different types of individuals (heterozooids) specialized in different functions such as defense or structural support for their colonies. Among them, the best-known heterozooids are the avicularia, known to function as defenders. The differentiation processes of heterozooids, including avicularia, should be important keys to understand the evolutionary significance of bryozoans. However, the developmental process of avicularium formation remains to be fully understood. In this study, therefore, in order to understand the detailed developmental process and timing of avicularium formation, extensive observations were carried out in a bryozoan species, Bugulina californica (Cheilostomata, Bugulidae), that possesses adventitious avicularia, by performing stereomicroscopy on live materials, in addition to scanning electron microscopy and histological observations. The whole process can be divided into seven stages based on developmental events. Especially notably, at the earlier stages, there are three major budding events that produce proliferating cell masses corresponding to primordial tissues: (1) budding of the peduncle cushion at the outer margin of the distal part of a young autozooid, (2) budding of the head-part primordium from the peduncle cushion, and (3) budding of the polypide inside the head part. Experimental control of temperature showed that 20°C would be the best to maintain B. californica colonies.


Assuntos
Briozoários/crescimento & desenvolvimento , Animais , Evolução Biológica , Briozoários/genética , Briozoários/ultraestrutura , Microscopia Eletrônica de Varredura
3.
Zootaxa ; 4903(1): zootaxa.4903.1.5, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33757107

RESUMO

Two new deep-sea Henricia species, Henricia margarethae n. sp. and Henricia fragilis n. sp. are described from Sagami Bay and the Ogasawara Islands in Japan. The two new species show an affinity with eight congeners in having multiple furrow spines and abactinal papular areas which are larger than surrounding plates. The two species described herein are characterized by the arrangement of abactinal pseudopaxillae, the arrangement of abactinal papulae, the shape and arrangement of abactinal spines, the length of intermarginal and ventrolateral series, and the armament of superomarginal, inferomarginal, and adambulacral plates.


Assuntos
Estrelas-do-Mar , Animais , Japão
4.
J Morphol ; 282(2): 205-216, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33159480

RESUMO

Basket stars, that is, Ophiuroidea in Echinodermata, exhibit distinctive morphological characteristics with their complicatedly branched arms that can regenerate immediately after mutilation. Although, in brittle stars, that is, ophiuroids with nonbranched arms, the arm regeneration process following accidental trauma or autotomy have been morphologically and histologically observed in several species, few studies have so far been carried out on the regeneration of branched arms in basket stars. In this study, the developmental and morphological features of arm regeneration in Astrocladus dofleini (Gorgonocephalidae, Euryalida, Euryophiurida), one of the most common basket star species in Japanese waters, was anatomically and histologically investigated. Results clearly showed the following phases during the arm regeneration: (a) repair phase, (b) early regenerative phase, (c) intermediate regenerative phase, (d) advanced regenerative Phase I, and (e) advanced regenerative Phase II. The morphogenetic process during the arm regeneration in the basket star showed similar patterns to those of nonbranched arms observed in other ophiuroids. However, differences were also seen between the two ophiuroid types, that is, there were some developmental features specific to the basket star. In the early regenerative phase, branching of coelomic cavities was observed prior to the formation of other tissues, probably inducing the later morphogenesis of branched arms. In addition, hard skeletal ossicles form rapidly at the advanced regenerative Phase II. These developmental features may have led the evolution of bizarre morphologies seen in basket stars, probably contributing to the adaptation to shallow waters from deep-sea habitats.


Assuntos
Equinodermos/anatomia & histologia , Equinodermos/fisiologia , Morfogênese , Animais , Equinodermos/citologia , Sistema Musculoesquelético/anatomia & histologia , Regeneração
5.
PeerJ ; 8: e9836, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33083106

RESUMO

Japanese species of the genus Astrocladus (Echinodermata, Ophiuroidea, Euryalida, Gorgonocephalidae) are reviewed. Astrocladus coniferus recently has two junior synonyms, A. dofleini Döderlein and A. pardalis Döderlein, however, status of these species has long been questioned. These species concepts have not been reviewed in recent years and no molecular phylogenetic analyses have been performed. Observations of the lectotype of A. coniferus, as well as the lectotype and four paralectotypes of A. dofleini and the holotype of A. pardalis have revealed that A. coniferus and A. pardalis are conspecific and morphologically distinguishable from A. dofleini. Astrocladus coniferus and A. dofleini are supported as distinct species by our molecular data. Additionally, we re-describe A. exiguus and A. annulatus, based on recently collected specimens and the holotype. We conclude that four species, A. annulatus, A. coniferus, A. dofleini, and A. exiguus are present in Japanese waters.

6.
Zoolog Sci ; 37(5): 496-503, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32972090

RESUMO

We describe Obesostoma crinophilum sp. nov. (Ostracoda: Podocopida: Paradoxostomatidae) obtained from the body surface of the feather star Antedon serrata A. H. Clark, 1908 (Crinoidea: Comatulida: Antedonidae). This is the first report of Ostracoda associated with Crinoidea. None of the highly specialized appendages and/or carapace that are related to a commensal lifestyle were observed in O. crinophilum sp. nov. Therefore, the relationship between O. crinophilum sp. nov. and A. serrata must be transient rather than obligatory. However, O. crinophilum sp. nov. has a more developed hook-like distal claw on the antenna in comparison with four previously known Obesostoma species. The relatively well-developed distal claw of the antenna in O. crinophilum sp. nov. should indicate its intimate association with feather stars, though the feeding habit is still unknown.


Assuntos
Crustáceos/classificação , Equinodermos/fisiologia , Simbiose , Animais , Crustáceos/anatomia & histologia , Feminino , Masculino , Especificidade da Espécie
7.
Front Zool ; 17: 24, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32855651

RESUMO

Background: Morphological novelties have been acquired through evolutionary processes and related to the adaptation of new life-history strategies with new functions of the bodyparts. Cephalopod molluscs such as octopuses, squids and cuttlefishes possess unique morphological characteristics. Among those novel morphologies, in particular, suckers arranged along the oral side of each arm possess multiple functions, such as capturing prey and locomotion, so that the sucker morphology is diversified among species, depending on their ecological niche. However, the detailed developmental process of sucker formation has remained unclear, although it is known that new suckers are formed or added during both embryonic and postembryonic development. In the present study, therefore, focusing on two cuttlefish species, Sepia esculenta and S. lycidas, in which the sucker morphology is relatively simple, morphological and histological observations were carried out during embryonic and postembryonic development to elucidate the developmental process of sucker formation and to compare them among other cephalopod species. Results: The observations in both species clearly showed that the newly formed suckers were added on the oral side of the most distal tip of each arm during embryonic and postembryonic development. On the oral side of the arm tip, the epithelial tissue became swollen to form a ridge along the proximal-distal axis (sucker field ridge). Next to the sucker field ridge, there were small dome-shaped bulges that are presumed to be the sucker buds. Toward the proximal direction, the buds became functional suckers, in which the inner tissues differentiated to form the complex sucker structures. During postembryonic development, on both sides of the sucker field ridge, epithelial tissues extended to form a sheath, covering the ridge for protection of undifferentiated suckers. Conclusions: The developmental process of sucker formation, in which sucker buds are generated from a ridge structure (sucker field ridge) on the oral side at the distal-most arm tip, was shared in both cuttlefish species, although some minor heterochronic shifts of the developmental events were detected between the two species.(325 words).

8.
Biomolecules ; 10(1)2019 12 25.
Artigo em Inglês | MEDLINE | ID: mdl-31881787

RESUMO

Many marine invertebrates have a life cycle with planktonic larvae, although the evolution of this type of life cycle remains enigmatic. We recently proposed that the regulatory mechanism of life cycle transition is conserved between jellyfish (Cnidaria) and starfish (Echinoderm); retinoic acid (RA) signaling regulates strobilation and metamorphosis, respectively. However, the function of RA signaling in other animal groups is poorly understood in this context. Here, to determine the ancestral function of RA signaling in echinoderms, we investigated the role of RA signaling during the metamorphosis of the feather star, Antedon serrata (Crinoidea, Echinodermata). Although feather stars have different larval forms from starfish, we found that exogenous RA treatment on doliolaria larvae induced metamorphosis, like in starfish. Furthermore, blocking RA synthesis or binding to the RA receptor suppressed metamorphosis. These results suggested that RA signaling functions as a regulator of metamorphosis in the ancestor of echinoderms. Our data provides insight into the evolution of the animal life cycle from the viewpoint of RA signaling.


Assuntos
Equinodermos/crescimento & desenvolvimento , Equinodermos/metabolismo , Estágios do Ciclo de Vida , Transdução de Sinais , Tretinoína/metabolismo , Animais
9.
J Vis Exp ; (150)2019 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-31449240

RESUMO

Traditionally, biologists have had to rely on destructive methods such as sectioning in order to investigate the internal structures of opaque organisms. Non-destructive microfocus X-ray computed tomography (microCT) imaging has become a powerful and emerging protocol in biology, due to technological advancements in sample staining methods and innovations in microCT hardware, processing computers, and data analysis software. However, this protocol is not commonly used, as it is in the medical and industrial fields. One of the reasons for this limited use is the lack of a simple and comprehensible manual that covers all of the necessary steps: sample collection, fixation, staining, mounting, scanning, and data analyses. Another reason is the vast diversity of metazoans, particularly marine invertebrates. Because of marine invertebrates' diverse sizes, morphologies, and physiologies, it is crucial to adjust experimental conditions and hardware configurations at each step, depending on the sample. Here, microCT imaging methods are explained in detail using three phylogenetically diverse marine invertebrates: Actinia equina (Anthozoa, Cnidaria), Harmothoe sp. (Polychaeta, Annelida), and Xenoturbella japonica (Xenoturbellida, Xenacoelomorpha). Suggestions on performing microCT imaging on various animals are also provided.


Assuntos
Organismos Aquáticos/patogenicidade , Invertebrados/patogenicidade , Microtomografia por Raio-X/métodos , Animais
10.
J Nat Med ; 73(4): 814-819, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31054009

RESUMO

Two new steroidal saponins, scrobiculosides A and B, were isolated from the deep-sea sponge Pachastrella scrobiculosa, collected at a depth of 200 m off Miura Peninsula, Japan. The aglycones of scrobiculosides A and B feature a vinylic cyclopropane and a ∆24,25 exomethylene on the side chains, respectively. Both saponins have a common sugar moiety composed of ß-D-galactopyranosyl-(1 → 2)-6-acetyl-ß-D-glucopyranoside, with the exception of an acetyl group on C6″ in scrobiculoside A. Scrobiculoside A exhibited cytotoxicity against HL-60 and P388 cells, with IC50 values of 52 and 61 µM, respectively.


Assuntos
Poríferos/metabolismo , Saponinas/isolamento & purificação , Saponinas/farmacologia , Esteroides/farmacologia , Animais , Linhagem Celular Tumoral , Células HL-60 , Humanos , Japão , Estrutura Molecular , Saponinas/química , Esteroides/química , Esteroides/isolamento & purificação
11.
Zootaxa ; 4455(3): 429-453, 2018 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-30314192

RESUMO

Four new dendrochirotid sea cucumbers, Neocucumis misakiensis sp. nov., Pseudocolochirus misakiensis sp. nov., Lipotrapeza purpurata sp. nov., and Pentamera misakiensis sp. nov., and three other known species, Amphicyclus japonicus Bell, 1884, Cucumaria tegulata Augustin, 1908, and Placothuria ohshimai Liao, 1997, are described from off Jyogashima Island, Misaki peninsula, south coast of Kanagawa Prefecture, Japan. In this study, Cucumaria tegulata Augustin, 1908, is referred to the genus Hemiocnus Mjobo Thandar, 2016. Furthermore, a new phyllophorid genus Pseudoplacothuria is here erected to accommodate Placothuria ohshimai Liao, 1997. Although its external and internal body morphology and most of the ossicle morphology resemble those of Pentamera spp., it differs in possessing thick lens-shaped ossicles in the body wall, and also in possessing needle-shaped ossicles in the gonadal tubules.


Assuntos
Equinodermos , Pepinos-do-Mar , Animais , Cucumaria , Japão
12.
BMC Evol Biol ; 18(1): 83, 2018 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-29879905

RESUMO

After publication of Nakano et al. (2017) [1], the authors became aware of the fact that the new species-group name erected for the two specimens of a Japanese xenoturbellid species in the article is not available because Nakano et al. (2017) [1] does not meet the requirement of the amendment of Article 8.5.3 of the International Code of Zoological Nomenclature (the Code) [2]. The authors therefore describe the two xenoturbellids as a new species again in this correction article. Methods for morphological observation, DNA extraction and sequencing were as described in Nakano et al. (2017) [1]. The holotype and paratype specimens are deposited in the National Museum of Nature and Science, Tsukuba (NSMT), Japan. The DNA sequences obtained were deposited in the International Nucleotide Sequence Database (INSD).

13.
J Nat Prod ; 81(4): 1108-1112, 2018 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-29613787

RESUMO

Morphology-guided cell-based screening of the extract of a Mycale sp. marine sponge led to the isolation of two trisoxazole macrolides, miuramides A (1) and B (2), which induced characteristic morphological changes in 3Y1 cells. The structure of 1 including absolute configuration was elucidated by a combination of the analysis of spectroscopic data, derivatization, and degradation. Both compounds exhibit potent cytotoxicity against 3Y1 cells.


Assuntos
Macrolídeos/química , Macrolídeos/farmacologia , Oxazóis/química , Oxazóis/farmacologia , Poríferos/química , Animais , Linhagem Celular , Citotoxinas/química , Citotoxinas/farmacologia , Mamíferos , Fenótipo , Ratos
14.
BMC Evol Biol ; 17(1): 245, 2017 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-29249199

RESUMO

BACKGROUND: Xenoturbella is a group of marine benthic animals lacking an anus and a centralized nervous system. Molecular phylogenetic analyses group the animal together with the Acoelomorpha, forming the Xenacoelomorpha. This group has been suggested to be either a sister group to the Nephrozoa or a deuterostome, and therefore it may provide important insights into origins of bilaterian traits such as an anus, the nephron, feeding larvae and centralized nervous systems. However, only five Xenoturbella species have been reported and the evolutionary history of xenoturbellids and Xenacoelomorpha remains obscure. RESULTS: Here we describe a new Xenoturbella species from the western Pacific Ocean, and report a new xenoturbellid structure - the frontal pore. Non-destructive microCT was used to investigate the internal morphology of this soft-bodied animal. This revealed the presence of a frontal pore that is continuous with the ventral glandular network and which exhibits similarities with the frontal organ in acoelomorphs. CONCLUSIONS: Our results suggest that large size, oval mouth, frontal pore and ventral glandular network may be ancestral features for Xenoturbella. Further studies will clarify the evolutionary relationship of the frontal pore and ventral glandular network of xenoturbellids and the acoelomorph frontal organ. One of the habitats of the newly identified species is easily accessible from a marine station and so this species promises to be valuable for research on bilaterian and deuterostome evolution.


Assuntos
Evolução Biológica , Invertebrados/anatomia & histologia , Animais , Oceano Pacífico , Filogenia , Especificidade da Espécie , Microtomografia por Raio-X
15.
Comp Biochem Physiol B Biochem Mol Biol ; 158(4): 266-73, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21176791

RESUMO

A lectin - designated OXYL for the purposes of this study that strongly recognizes complex-type oligosaccharides of serum glycoproteins - was purified from a crinoid, the feather star Oxycomanthus japonicus, the most basal group among extant echinoderms. OXYL was purified through a combination of anion-exchange and affinity chromatography using Q-sepharose and fetuin-sepharose gel, respectively. Lectin was determined to be a 14-kDa polypeptide by sodium dodecyl sulphate-polyacrylamide gel electrophoresis under reducing conditions. However, 14-kDa and 28-kDa bands appeared in the same proportion under non-reducing conditions. Gel permeation chromatography showed a 54-kDa peak, suggesting that lectin consists of four 14-kDa subunits. Divalent cations were not indicated, and stable haemagglutination activity was demonstrated at pH 4-12 and temperatures below 60°C. Surface plasmon resonance analysis of OXYL against fetuin showed k(ass) and k(diss) values of 1.4×10(-6)M(-1)s(-1) and 3.1×10(-3)s(-1), respectively, indicating that it has a strong binding affinity to the glycoprotein as lectin. Frontal affinity chromatography using 25 types of prydylamine-conjugated glycans indicated that OXYL specifically recognizes multi-antennary complex-type oligosaccharides containing type-2 N-acetyllactosamines (Galß1-4GlcNAc) if α2-3-linked sialic acid is linked at the non-reducing terminal. However, type-1 N-acetyllactosamine (Galß1-3GlcNAc) chains and α2-6-linked sialic acids were never recognized by OXYL. This profiling study showed that OXYL essentially recognizes ß1-4-linkage at C-1 position and free OH group at C-6 position of Gal in addition to the conservation of N-acetyl groups at C-2 position and free OH groups at C-3 position of GlcNAc in N-acetyllactosamine. This is the first report on glycomics on a lectin purified from an echinoderm belonging to the subphylum Pelmatozoa.


Assuntos
Amino Açúcares/metabolismo , Equinodermos/química , Lectinas/metabolismo , Animais , Cátions Bivalentes/química , Dissacarídeos/metabolismo , Glicômica , Concentração de Íons de Hidrogênio , Lectinas/química , Lectinas/isolamento & purificação , Peso Molecular , Monossacarídeos/metabolismo , Polissacarídeos/metabolismo , Ressonância de Plasmônio de Superfície , Temperatura
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