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1.
BMC Genomics ; 25(1): 655, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38956468

RESUMO

The Sox gene family, a collection of transcription factors widely distributed throughout the animal kingdom, plays a crucial role in numerous developmental processes. Echinoderms occupy a pivotal position in many research fields, such as neuroscience, sex determination and differentiation, and embryonic development. However, to date, no comprehensive study has been conducted to characterize and analyze Sox genes in echinoderms. In the present study, the evolution and expression of Sox family genes across 11 echinoderms were analyzed using bioinformatics methods. The results revealed a total of 70 Sox genes, with counts ranging from 5 to 8 across different echinoderms. Phylogenetic analysis revealed that the identified Sox genes could be categorized into seven distinct classes: the SoxB1 class, SoxB2 class, SoxC class, SoxD class, SoxE class, SoxF class and SoxH class. Notably, the SoxB1, SoxB2, and SoxF genes were ubiquitously present in all the echinoderms studied, which suggests that these genes may be conserved in echinoderms. The spatiotemporal expression patterns observed for Sox genes in the three echinoderms indicated that various Sox members perform distinct functional roles. Notably, SoxB1 is likely involved in echinoderm ovary development, while SoxH may play a crucial role in testis development in starfish and sea cucumber. In general, the present investigation provides a molecular foundation for exploring the Sox gene in echinoderms, providing a valuable resource for future phylogenetic and genomic studies.


Assuntos
Equinodermos , Família Multigênica , Filogenia , Fatores de Transcrição SOX , Animais , Fatores de Transcrição SOX/genética , Fatores de Transcrição SOX/metabolismo , Equinodermos/genética , Perfilação da Expressão Gênica , Evolução Molecular , Regulação da Expressão Gênica no Desenvolvimento , Biologia Computacional/métodos
2.
Sci Rep ; 14(1): 15300, 2024 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961160

RESUMO

High Latitude fjords can serve as sediment trap, bearing different type of proxies, from geochemical to micropaleontological ones, making them exceptional tools for paleoenvironmental reconstruction. However, some unconventional proxies can be present and can be used to depict a comprehensive and exhaustive interpretation of past changes. Here, studying a sediment core in Edisto Inlet (Ross Sea, Antarctica) we used irregular echinoid spines and ophiuroids (Ophionotus victoriae) ossicles to trace environmental changes throughout the last 3.6 kyrs BP. Irregular echinoids can serve as proxy for the organic matter content, while O. victoriae ossicles can be used as proxy for steady sea-ice cycle along with organic deposition events. O. victoriae release a high number of ossicles, making estimation about the population quite challenging; still, presence data, can be easily collected. By applying Generative Additive Models to the stratigraphical distribution of these data, we detected an environmental phase that was previously unnoticed by other traditional proxies: the Ophiuroid Optimum (2-1.5 kyrs BP). In conclusion, here we demonstrate how echinoderm presence can be used as a valuable source of information, while proving the potential of modelling binary data to detect long-term trend in Holocene stratigraphical records.


Assuntos
Equinodermos , Fósseis , Sedimentos Geológicos , Regiões Antárticas , Animais , Sedimentos Geológicos/análise , Paleontologia/métodos
3.
Sci Rep ; 14(1): 13238, 2024 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-38853171

RESUMO

The European brittle star Amphiura filiformis emits blue light, via a Renilla-like luciferase, which depends on the dietary acquisition of coelenterazine. Questions remain regarding luciferin availability across seasons and the persistence of luminous capabilities after a single boost of coelenterazine. To date, no study has explored the seasonal, long-term monitoring of these luminous capabilities or the tracking of luciferase expression in photogenic tissues. Through multidisciplinary analysis, we demonstrate that luminous capabilities evolve according to the exogenous acquisition of coelenterazine throughout adult life. Moreover, no coelenterazine storage forms are detected within the arms tissues. Luciferase expression persists throughout the seasons, and coelenterazine's presence in the brittle star diet is the only limiting factor for the bioluminescent reaction. No seasonal variation is observed, involving a continuous presence of prey containing coelenterazine. The ultrastructure description provides a morphological context to investigate the green autofluorescence signal attributed to coelenterazine during luciferin acquisition. Finally, histological analyses support the hypothesis of a pigmented sheath leading light to the tip of the spine. These insights improve our understanding of the bioluminescence phenomenon in this burrowing brittle star.


Assuntos
Pirazinas , Estações do Ano , Animais , Pirazinas/metabolismo , Imidazóis , Equinodermos , Luminescência , Luciferases/metabolismo , Luciferases/genética , Medições Luminescentes/métodos , Luz
4.
Proc Biol Sci ; 291(2023): 20232832, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38747704

RESUMO

Asexual reproduction by means of splitting, also called fissiparity, is a common feature in some asterozoan groups, especially in ophiactid brittle stars. Most fissiparous brittle stars show six instead of the usual five rays, live as epibionts on host organisms, and use clonal fragmentation to rapidly colonize secluded habitats and effectively expand the margins of their distribution area. While the biology and ecology of clonal fragmentation are comparatively well understood, virtually nothing is known about the evolution and geological history of that phenomenon. Here, we describe an exceptional fossil of an articulated six-armed brittle star from the Late Jurassic of Germany, showing one body half in the process of regeneration, and assign it to the new species Ophiactis hex sp. nov. Phylogenetic inference shows that the fossil represents the oldest member of the extant family Ophiactidae. Because the Ophiactis hex specimen shows an original six-fold symmetry combined with a morphology typically found in epizoic ophiuroids, in line with recent fissiparous ophiactid relatives, we assume that the regenerating body half is an indication for fissiparity. Ophiactis hex thus shows that fissiparity was established as a means of asexual reproduction in asterozoan echinoderms by the Late Jurassic.


Assuntos
Equinodermos , Fósseis , Filogenia , Reprodução Assexuada , Animais , Fósseis/anatomia & histologia , Equinodermos/anatomia & histologia , Equinodermos/fisiologia , Evolução Biológica , Alemanha
5.
Sci Data ; 11(1): 560, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816401

RESUMO

The cold-water species Ophiura sarsii, a brittle star, is a key echinoderm in the Arctic continental shelf region, highly sensitive to climate change. However, the absence of a high-quality genome has hindered a thorough understanding of its adaptive evolution. In this study, we reported the first chromosome-level genome assembly of O. sarsii. The genome assembly totalled 1.57 Gb, encompassing 19 chromosomes with a GC content of 37.11% and a scaffold N50 length of 78.03 Mb. The Benchmarking Universal Single-Copy Orthologs (BUSCO) assessment yielded a completeness estimate of 93.5% for this assembly. We predicted a total of 27,099 protein-coding genes, with 25,079 functionally annotated. The genome was comprised of 58.09% transposable elements. This chromosome-level genome of O. sarsii contributes to our understanding of the origin and evolution of marine organisms.


Assuntos
Cromossomos , Equinodermos , Genoma , Animais , Equinodermos/genética , Anotação de Sequência Molecular , Composição de Bases , Elementos de DNA Transponíveis
6.
Elife ; 122024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38573316

RESUMO

Biomineralization had apparently evolved independently in different phyla, using distinct minerals, organic scaffolds, and gene regulatory networks (GRNs). However, diverse eukaryotes from unicellular organisms, through echinoderms to vertebrates, use the actomyosin network during biomineralization. Specifically, the actomyosin remodeling protein, Rho-associated coiled-coil kinase (ROCK) regulates cell differentiation and gene expression in vertebrates' biomineralizing cells, yet, little is known on ROCK's role in invertebrates' biomineralization. Here, we reveal that ROCK controls the formation, growth, and morphology of the calcite spicules in the sea urchin larva. ROCK expression is elevated in the sea urchin skeletogenic cells downstream of the Vascular Endothelial Growth Factor (VEGF) signaling. ROCK inhibition leads to skeletal loss and disrupts skeletogenic gene expression. ROCK inhibition after spicule formation reduces the spicule elongation rate and induces ectopic spicule branching. Similar skeletogenic phenotypes are observed when ROCK is inhibited in a skeletogenic cell culture, indicating that these phenotypes are due to ROCK activity specifically in the skeletogenic cells. Reduced skeletal growth and enhanced branching are also observed under direct perturbations of the actomyosin network. We propose that ROCK and the actomyosin machinery were employed independently, downstream of distinct GRNs, to regulate biomineral growth and morphology in Eukaryotes.


Assuntos
Actomiosina , Fator A de Crescimento do Endotélio Vascular , Animais , Citoesqueleto de Actina , Ouriços-do-Mar , Equinodermos , Eucariotos
7.
Rev. biol. trop ; 72(supl.1): e59013, Mar. 2024. tab, graf
Artigo em Inglês | LILACS, SaludCR | ID: biblio-1559343

RESUMO

Abstract Introduction: Short-term gametes storage is an inexpensive and simple technique that allows the use of the same batch of eggs or sperm at different times, maximizing the application of research protocols and the use of gametes in production. Arbacia dufresnii is a sea urchin species with proven aquaculture potential and already used in the nutraceutical industry. Aging of its gametes is unknown and is a needed information to scale up the production. Objective: Determine the effect of male and female gamete aging on the fertilization success of Arbacia dufresnii. This will allow optimizing the use of gametes after collection decoupling spawning from fertilization. Methods: A. dufresnii individuals were induced to spawn and gametes were kept at 12 ± 1 °C throughout each bioassay. Sperm was separated into two treatments: activated sperm in seawater (AS), and dry sperm (DS). Two bioassays were made: Bioassay 1 evaluated the effect of time on fertility by performing fertilization tests at 0 h, 24 h, 48 h, 72 h, and 96 h after spawning. Bioassay 2 evaluated the contribution of each type of aged gamete on fertility, combining aged gametes (96 h) with fresh gametes (0 h). Results: Bioassay 1: the fertilization success obtained by combining eggs (E) with AS or DS presented important differences. While the fertilization success remained acceptable (greater than 50 %) for up to 72 h using ExDS, it only remained acceptable for up to 48 h using ExAS. Bioassay 2: acceptable fertilization success was found by combining aged E (96 h) with fresh sperm, or aged DS (96 h) with fresh E, but not using aged AS with fresh E. Conclusions: The findings of this work show that fertilization success in A. dufresnii gametes remains relatively unchanged for up to 48 h after spawning when combining ExAS, and for up to 72 h when combining ExDS. However, when combining aged E or aged DS with a fresh gamete, post-collection fertilization can be extended up to 96 h. In this work, the first steps have been taken to understand the conservation time of A. dufresnii gametes with minimum intervention.


Resumen Introducción: El almacenamiento de gametos a corto plazo es una técnica económica y sencilla que permite utilizar el mismo lote de óvulos o espermatozoides en diferentes momentos, maximizando la aplicación de protocolos de investigación y el uso de gametos en la producción. Arbacia dufresnii es una especie con probado potencial acuícola como fuente de gametos para la industria nutracéutica. Sin embargo, se desconoce el envejecimiento de sus gametos y es una información necesaria para escalar la producción. Objetivo: Determinar el efecto del envejecimiento de los gametos masculinos y femeninos en el éxito de la fecundación de Arbacia dufresnii con el fin de optimizar el aprovechamiento de los gametos después de la recolecta desincronizando el desove de la fecundación. Métodos: Se indujo el desove de individuos de A. dufresnii y los gametos se mantuvieron a 12 ± 1 °C durante cada bioensayo. El esperma se separó en dos tratamientos: esperma activado en agua de mar (AS) y esperma seco (DS). Se realizaron dos bioensayos: El Bioensayo 1 evaluó el efecto del tiempo sobre la fertilidad realizando pruebas de fecundación a las 0 h, 24 h, 48 h, 72 h y 96 h después del desove. El bioensayo 2 evaluó la contribución de cada tipo de gameta envejecida (96 h) sobre la fertilidad, combinando gametos envejecidas (96 h) con gametos frescas (0 h). Resultados: Bioensayo 1: el éxito de fecundación obtenido combinando huevos (E) con AS o DS presentó diferencias importantes. Si bien el éxito de la fecundación se mantuvo aceptable (más del 50 %) durante un máximo de 72 h con ExDS, solo permaneció aceptable hasta 48 h con ExAS. Bioensayo 2: se encontró un éxito de fecundación aceptable combinando E envejecidos (96 h) con esperma fresco, o DS envejecido (96 h) con E fresco (0 h), pero no usando AS envejecido con E fresco (0 h). Conclusiones: Los hallazgos de este trabajo muestran que el éxito de la fecundación en los gametos de A. dufresnii permanece relativamente sin cambios hasta 48 h después del desove cuando se combina ExAS, y hasta 72 h cuando se combina ExDS. Sin embargo, cuando se combina E envejecido o DS envejecido con un gameto fresco, el tiempo entre la recolección y la fecundación puede extenderse hasta 96 h. En este trabajo se han dado los primeros pasos para entender el tiempo de conservación de los gametos de A. dufresnii con mínima intervención.


Assuntos
Animais , Reprodução , Ouriços-do-Mar/embriologia , Bioensaio , Equinodermos/crescimento & desenvolvimento , Células Germinativas/crescimento & desenvolvimento
8.
Rev. biol. trop ; 72(supl.1): e58997, Mar. 2024. tab, graf
Artigo em Inglês | LILACS, SaludCR | ID: biblio-1559342

RESUMO

Abstract Introduction: Molecular divergence thresholds have been proposed to distinguish recently separated evolutive units, often displaying more accurate putative species assignments in taxonomic research compared to traditional morphological approaches. This makes DNA barcoding an attractive identification tool for a variety of marine invertebrates, especially for cryptic species complexes. Although GenBank and the Barcode of Life Data System (BOLD) are the major sequence repositories worldwide, very few have tested their performance in the identification of echinoderm sequences. Objective: We use COI echinoderm sequences from local samples and the molecular identification platforms from GenBank and BOLD, in order to test their accuracy and reliability in the DNA barcoding identification for Central American shallow water echinoderms, at genus and species level. Methods: We conducted sampling, tissue extraction, COI amplification, sequencing, and taxonomic identification for 475 specimens. The 348 obtained sequences were individually enquired with BLAST in GenBank as well as using the Identification System (IDS) in BOLD. Query sequences were classified depending on the best match result. McNemar's chi-squared, Kruskal-Wallis's and Mann-Whitney's U tests were performed to prove differences between the results from both databases. Additionally, we recorded an updated list of species reported for the shallow waters of the Central American Pacific. Results: We found 324 echinoderm species reported for Central American Pacific shallow waters. Only 118 and 110 were present in GenBank and BOLD databases respectively. We proposed 325 solved morphology-based identities and 21 provisional identifications in 50 putative taxa. GenBank retrieved 348 molecular-based identifications in 58 species, including twelve provisional identifications in tree taxa. BOLD recovered 170 COI identifications in 23 species with one provisional identification. Nevertheless, 178 sequences retrieved unmatched terms (in 34 morphology-based taxa). Only 86 sequences (25 %) were retrieved as correct identifications and 128 (37 %) as identification errors in both platforms. We include 84 sequences for eleven species not represented in GenBank and 65 sequences for ten species in BOLD Echinoderm COI databases. The identification accuracy using BLAST (175 correct and 152 incorrect identifications) was greater than with IDS engine (110 correct and 218 identification errors), therefore GenBank outperforms BOLD (Kruskal-Wallis = 41.625, df = 1, p < 0.001). Conclusions: Additional echinoderm sample references are needed to improve the utility of the evaluated DNA barcoding identification tools. Identification discordances in both databases may obey specific parameters used in each search algorithm engine and the available sequences. We recommend the use of barcoding as a complementary identification source for Central American Pacific shallow water echinoderm species.


Resumen Introducción: Se han propuesto los umbrales de divergencia molecular para distinguir unidades evolutivas recientemente separadas, que a menudo muestran asignaciones de especies putativas más precisas en la investigación taxonómica en comparación con los enfoques morfológicos tradicionales. Esto hace que los Códigos de Barras de ADN sean una herramienta de identificación atractiva para una variedad de invertebrados marinos, especialmente para complejos de especies crípticas. Aunque GenBank y Barcode of Life Data System (BOLD) son los principales repositorios de secuencias en todo el mundo, muy pocos han probado su desempeño en la identificación de secuencias de equinodermos. Objetivo: Utilizamos secuencias de equinodermos COI de muestras locales y las plataformas de identificación molecular de GenBank y BOLD, para probar su precisión y confiabilidad en la implementación de códigos de barras de ADN para equinodermos de aguas someras de Centroamérica, a nivel de género y especie. Métodos: Realizamos muestreo, extracción de tejido, amplificación de COI, secuenciación e identificación taxonómica de 475 especímenes. Las 348 secuencias obtenidas fueron consultadas individualmente con BLAST en GenBank así como utilizando el Sistema de Identificación (IDS) en BOLD. Las secuencias consultadas se clasificaron según el mejor resultado de coincidencia. Se realizaron las pruebas chi-cuadrado de McNemar, Kruskal-Wallis y U de Mann-Whitney para comprobar diferencias entre los resultados de ambas bases de datos. Además, registramos una lista actualizada de especies reportadas para las aguas someras del Pacífico Centroamericano. Resultados: Encontramos 324 especies de equinodermos reportadas para aguas someras (< 200 m) del Pacífico centroamericano. Sólo 118 y 110 estaban presentes en las bases de datos GenBank y BOLD respectivamente. Propusimos 325 identidades resueltas basadas en morfología y 21 identificaciones provisionales en 50 taxones putativos. GenBank recuperó 348 identificaciones de base molecular en 58 especies, incluidas doce identificaciones provisionales en tres taxones. BOLD recuperó 170 identificaciones de COI en 23 especies con una identificación provisional. Sin embargo, 178 secuencias recuperaron términos no coincidentes (en 34 taxones basados en morfología). Sólo 86 secuencias (25 %) se recuperaron como identificaciones correctas y 128 (37 %) como errores de identificación en ambas plataformas. Incluimos 84 secuencias para once especies no representadas en GenBank y 65 secuencias para diez especies ausentes en las bases de datos BOLD Echinoderm COI. La precisión de la identificación usando BLAST (175 identificaciones correctas y 152 incorrectas) fue mayor que con el motor IDS (110 correctas y 218 errores de identificación), por lo tanto, GenBank supera a BOLD (Kruskal-Wallis = 41.625, df = 1, p < 0.001). Conclusiones: Se necesitan muestras adicionales de equinodermos de referencia para mejorar la utilidad de las herramientas de identificación de códigos de barras de ADN evaluadas. Las discordancias de identificación en ambas bases de datos pueden obedecer a parámetros específicos utilizados en cada algoritmo de búsqueda y a las secuencias disponibles. Recomendamos el uso de códigos de barras como fuente de identificación complementaria para las especies de equinodermos de aguas someras del Pacífico centroamericano.


Assuntos
Animais , DNA , Processamento Eletrônico de Dados , Equinodermos/classificação , Amostragem Estratificada , Costa Rica
9.
Rev. biol. trop ; 72(supl.1): e58980, Mar. 2024. tab, graf
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1559335

RESUMO

Resumen Introducción: Los equinodermos son animales estrictamente acuáticos y de los grupos de invertebrados marinos cuya importancia ecológica es crucial para los ambientes en donde habitan. La característica más destacada es su simetría pentarradial. Estos organismos pueden distribuirse en una amplia variedad de ambientes oceánicos, y no ser exclusivamente habitantes de las formaciones arrecifales. Se han registrado el total de 1 539 especies, de las cuales 717 pertenecen a Pacífico y 60 de ellas se han registrado en El Salvador. Objetivo: El objetivo del trabajo fue registrar la riqueza y densidad de especies de equinodermos en arrecifes rocosos de Punta Amapala (La Unión). Métodos: El muestreo fue llevado a cabo en cinco sitios, dos a 3 m de profundidad y tres a 6 m. Para esto, se utilizó snorkeling y buceo autónomo, recorriendo dos transectos de banda de 30 x 1 m. Dentro de los transectos, se realizó la identificación (riqueza) y contabilización (abundancia) de los organismos. Resultados: La especie que presentó mayor densidad en los arrecifes de 3 m fue Echinometra vanbrunti (0.83 indv/m2), seguido por el ofiuroideo Ophiocomella alexandri (0.16 indv/m2) y Ophiocoma aethiops (0.16 indv/m2). Y en los arrecifes a 6 m fueron Ophiothela mirabilis (0.83 indv/m2), Ophionereis annulata (0.21 indv/m2), Ophiothrix rudis (0.08 indv/m2) y Ophiocomella alexandri (0.01 indv/m2). Conclusiones: Estos organismos, cumplen con diversos roles ecológicos, como ser bioindicadores de calidad de agua al tolerar ciertos cambios en las condiciones físico-químicas, así como cumplir el papel de hospederos de macrofauna por las cavidades que forman algunos erizos. Es por ello que los esfuerzos de muestreo deben incrementarse en estas zonas para monitorear la calidad y salud de los arrecifes rocosos, cuyo papel es clave, por ser junto con Los Cóbanos, los de mayor extensión en el país.


Abstract Introduction: Echinoderms are strictly aquatic animals and one of the groups of marine invertebrates whose ecological importance is crucial for the environments where they inhabit. The most outstanding characteristic is their pentaradial symmetry. These organisms can be distributed in a wide variety of oceanic environments, and are not exclusive inhabitants of reef formations. A total of 1 539 species have been registered, of which 717 belong to the Pacific and 60 of them have been registered for El Salvador. Objective: The objective of the work was to record the richness and density of echinoderm species in rocky reefs of Punta Amapala (La Unión). Methods: The sampling was conducted in five sites, two of them at 3 m of depth and three at 6 m. For this, snorkeling and autonomous diving were used, covering two band transects of 30 x 1 m. Within the transects, the identification (richness) and counting (abundance) of the organisms was carried out. Results: The species that presented the highest density at 3 m reefs was Echinometra vanbrunti (0.83 indv/m2), followed by the ophiuroid Ophiocomella alexandri (0.16 indv/m2) and Ophiocoma aethiops (0.16 indv/m2). And at the 6 m reefs were Ophiothela mirabilis (0.83 indv/m2), Ophionereis annulata (0.21 indv/m2), Ophiothrix rudis (0.08 indv/m2) and Ophiocomella alexandri (0.01 indv/m2). Conclusions: These organisms fulfill various ecological roles, such as being bioindicators of water quality by tolerating certain changes in physicochemical conditions and fulfilling the role of macrofauna hosts due to the cavities formed by some sea urchins. That is why sampling efforts must increase in these areas to monitor the quality and health of the rocky reefs, whose role is key, as they are, together with Los Cóbanos, the largest in the country.


Assuntos
Animais , Fauna Bentônica , Equinodermos/classificação , Estudos de Amostragem , El Salvador , Recifes de Corais
10.
Rev. biol. trop ; 72(supl.1): e58880, Mar. 2024. graf
Artigo em Inglês | LILACS, SaludCR | ID: biblio-1559333

RESUMO

Abstract Introduction: Echinoderms, an integral component of marine ecosystems worldwide, have captivated scientific interest for centuries. Despite this longstanding attention, comprehending key facets such as trophic relationships, diet composition, and host-microbiota relationships still represents a challenge using traditional techniques. Recent years, however, have witnessed a transformative shift, thanks to the emergence of advanced molecular techniques, offering new approaches to strengthen ecological studies in echinoderms. Objective: Explore how recent advancements in molecular tools have impacted ecological research on echinoderms. Specifically, we aim to investigate the potential of these tools to shed light on trophic interactions, diet composition, and the characterization of gut microbial communities in these organisms. Methods: Available literature was used to clarify how novel molecular techniques can improve ecological studies. The focus is diet, trophic relationships, and gut microbiota. Results: Traditionally, studies of stomach contents using compound microscopy have provided an idea of ingested material; nevertheless, sometimes a simple magnified visualization of dietary content does not allow exhaustive identification of the entire food spectrum, as it is limited due to the rapid digestion and maceration of food items within the echinoderm's digestive tract. The use of DNA-metabarcoding, targeting specific DNA regions, such as the mitochondrial COI gene, has allowed us to enhance the accuracy and precision of diet characterization by enabling the identification of prey items down to the species or even genetic variant level, providing valuable insights into specific dietary preferences. Another approach is the use of stable isotopes, particularly carbon and nitrogen, which provide a powerful tool to trace the origin and flow of nutrients through food webs. By analyzing the isotopic signatures in muscular tissues and food items, we can discern the sources of their primary food items and gain insights into their trophic position within the ecosystem. Lastly, a third new technique used to elucidate the characterization of the prokaryotic community is 16S rRNA sequencing. This method allows us to explore the composition and dynamics of the digestive tract microbial communities. Conclusions: This is a promising era for ecological research on echinoderms, where advances of molecular tools have enabled an unprecedented level of detail, resolving longstanding challenges in comprehending their trophic interactions, diet composition, and host-microbiota relationships, and opening new avenues of investigation in ecological studies.


Resumen Introducción: Los equinodermos, un componente integral de los ecosistemas marinos en todo el mundo, han captado el interés científico durante siglos. A pesar de esta prolongada atención, el comprender facetas clave como las relaciones tróficas, la composición de la dieta y las relaciones huésped-microbiota todavía representa un desafío utilizando técnicas tradicionales. Sin embargo, los últimos años han sido testigos de un cambio transformador, gracias a la aparición de técnicas moleculares avanzadas, que ofrecen nuevos enfoques para fortalecer los estudios ecológicos en equinodermos. Objetivo: Explorar cómo los avances recientes en herramientas moleculares han impactado la investigación ecológica sobre equinodermos. Específicamente, nuestro objetivo es investigar el potencial de estas herramientas para arrojar luz sobre las interacciones tróficas, la composición de la dieta y la caracterización de las comunidades microbianas intestinales en estos organismos. Métodos: Se utilizó la literatura disponible para aclarar cómo las nuevas técnicas moleculares pueden mejorar los estudios ecológicos. La atención se centra en la dieta, las relaciones tróficas y la microbiota intestinal. Resultados: Tradicionalmente, los estudios del contenido estomacal mediante microscopía compuesta han proporcionado una idea del material ingerido; Sin embargo, a veces una simple visualización ampliada del contenido dietético no permite una identificación exhaustiva de todo el espectro alimentario, ya que está limitado debido a la rápida digestión y maceración de los alimentos dentro del tracto digestivo del equinodermo. El uso de metabarcoding de ADN, dirigidos a regiones específicas del ADN, como el gen COI mitocondrial, nos ha permitido mejorar la exactitud y precisión de la caracterización de la dieta al permitir la identificación de presas hasta el nivel de especie o incluso de variante genética, lo que proporciona valiosos resultados sobre preferencias dietéticas específicas. Otro enfoque es el uso de isótopos estables, en particular carbono y nitrógeno, que proporcionan una poderosa herramienta para rastrear el origen y el flujo de nutrientes a través de las redes alimentarias. Al analizar las firmas isotópicas en los tejidos musculares y los alimentos, podemos discernir las fuentes de sus alimentos primarios y obtener información sobre su posición trófica dentro del ecosistema. Por último, una tercera técnica nueva utilizada para dilucidar la caracterización de la comunidad procariótica es la secuenciación del ARNr 16S. Este método nos permite explorar la composición y dinámica de las comunidades microbianas del tracto digestivo. Conclusiones: Esta es una era prometedora para la investigación ecológica sobre equinodermos, donde los avances de las herramientas moleculares han permitido un nivel de detalle sin precedentes, resolviendo desafíos de larga data en la comprensión de sus interacciones tróficas, composición de la dieta y relaciones huésped-microbiota, y abriendo nuevas vías de investigación. en estudios ecológicos.


Assuntos
Animais , Técnicas de Diagnóstico Molecular , Dieta , Equinodermos , DNA , Isótopos
11.
Rev. biol. trop ; 72(supl.1): e58618, Mar. 2024. tab, graf
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1559332

RESUMO

Resumen Introducción: Las colecciones biológicas representan los cimientos para el conocimiento y manejo de la biodiversidad de una región. No obstante, en México, y en particular en el Pacífico central mexicano (PCM), las colecciones regionales enfocadas en equinodermos, son escasas. La colección biológica del Laboratorio de Ecología Molecular, Microbiología y Taxonomía (LEMITAX) pertenece al Centro Universitario de Ciencias Biológicas y Agropecuarias de la Universidad de Guadalajara, Jalisco, México y sirve como referencia de la biodiversidad marina de la región. Objetivo: Dar a conocer la riqueza de equinodermos resguardada en la colección del LEMITAX. Métodos: Los organismos depositados en LEMITAX se han recolectado mediante buceo libre, SCUBA, y arrastres de fondo con dragas biológicas en diversas áreas del Pacífico mexicano. Los especímenes están preservados en húmedo (alcohol al 70 %; Asteroidea, Echinoidea, Holothuroidea y Ophiuroidea) o en seco (Asteroidea y Echinoidea). Resultados: Los especímenes provienen de los estados de Sinaloa, Nayarit, Jalisco y Colima, incluyendo dos áreas naturales protegidas, el Parque Nacional Isla Isabel y el Santuario de las islas e islotes de Bahía de Chamela. La colección dispone de 20 761 ejemplares de equinodermos distribuidos en 75 especies (10 asteroideos, 17 ofiuroideos, 17 equinoideos y 31 holoturoideos). El estado mejor representado es Jalisco (64 especies) seguido de Nayarit (31), Colima (20) y Sinaloa (11). Bahía de Chamela es la mejor representada (60), seguido de Isla Isabel (22). Se aportan 34 registros nuevos, la mayor contribución es para Bahía de Chamela con 14 registros nuevos, seguido del estado de Jalisco (siete), Nayarit (cuatro), Colima (tres) e Isla Isabel (tres). Para el PCM, se reporta por primera vez la presencia de Astropecten ornatissimus, Luidia phragma, Cucumaria crax y Holothuria (Cystipus) casoae, lo que actualiza su riqueza de equinodermos a 197 especies. Se amplía el intervalo de distribución batimétrica de Ophiactis simplex, Ophiocomella alexandri y Holothuria (Cystipus) casoae, así como el intervalo de distribución geográfica de Cucumaria crax. Conclusiones: Las colecciones biológicas de las universidades contribuyen de manera sustancial al conocimiento de la biodiversidad, como se refleja en la colección LEMITAX, cuya revisión resultó en la actualización de la riqueza de equinodermos de la región.


Abstract Introduction: The biological collections represent the foundation for the knowledge and management of the biodiversity of a region. However, regional collections focused on echinoderms are scarce in Mexico, particularly in the Central Mexican Pacific (CMP). The biological collection of the Laboratorio de Ecología Molecular, Microbiología y Taxonomía (LEMITAX) belongs to the Centro Universitario de Ciencias Biológicas y Agropecuarias of the Universidad de Guadalajara, Jalisco, Mexico and it aims to serve as a reference for the region's marine biodiversity. Objective: To state the richness of echinoderms in the LEMITAX collection. Methods: The organisms deposited at the LEMITAX have been collected by SCUBA, free-diving, and bottom trawls with biological dredges in different areas of the Mexican Pacific. The specimens are wet-preserved (70 % ethanol; Asteroidea, Echinoidea, Holothuroidea, and Ophiuroidea) or dried (Asteroidea and Echinoidea). Results: The specimens are from the states of Sinaloa, Nayarit, Jalisco, and Colima, including two natural protected areas (NPAs), the Isabel Island National Park and the sanctuary of the Islands and Islets of Bahía de Chamela. The collection has 20 761 specimens of echinoderms distributed in 75 species (10 asteroids, 17 ophiuroids, 17 echinoids, and 31 holothuroids). The best-represented state is Jalisco (64 species), followed by Nayarit (31), Colima (20), and Sinaloa (11). Concerning the NPAs, Chamela is the best represented (60), followed by Isabel Island (22). Thirty-four new records are added; the largest contribution is for Chamela, with 14 new records, followed by the state of Jalisco (seven), Nayarit (four), Colima (three), and Isabel Island (three). For the CMP, the presence of Astropecten ornatissimus, Luidia phragma, Cucumaria crax, and Holothuria (Cystipus) casoae, is reported for the first time, updating the echinoderm richness to 197 species. The bathymetric distribution range of Ophiactis simplex, Ophiocomella alexandri, and Holothuria (Cystipus) casoae is extended, as well as the geographic range of Cucumaria crax. Conclusions: The biological collections deposited in the universities contribute substantially to the knowledge of biodiversity, as reflected in the LEMITAX collection, whose revision resulted in the updating of the echinoderm richness in the region.


Assuntos
Animais , Equinodermos/classificação , Especificidade da Espécie , México
12.
Rev. biol. trop ; 72(supl.1): e58786, Mar. 2024. tab, graf
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1559328

RESUMO

Resumen Introducción: Las especies de las clases Crinoidea y Asteroidea se distribuyen en gran variedad de hábitats en todos los océanos desde la zona intermareal hasta grandes profundidades, existen pocos registros en aguas mexicanas, a profundidades superiores a los 200 m, los escasos registros existentes datan de documentos históricos de la literatura especializada y los ejemplares se resguardan en colecciones científicas extranjeras. Objetivo: Contribuir a la recopilación de información de los ejemplares resguardados en la Colección Nacional de Equinodermos (CNE) del Instituto de Ciencias del Mar y Limnología (ICML), UNAM y proveer un inventario de las especies de crinoideos y asteroideos que habitan en zonas profundas del talud de la Península de Yucatán, México. Métodos: Del año 2005 al 2014 se recolectaron ejemplares de crinoideos y asteriodeos en cuatro cruceros en el B/O "Justo Sierra" BIOREPES 1 y 2 y COBERPES 2 y 6. Se realizaron arrastres con red camaronera en 80 estaciones de muestreo. Resultados: El listado taxonómico comprende 1146 ejemplares, de los cuales 204 son crinoideos del orden Comatulida, distribuidos en tres familias tres géneros y tres especies y 942 asteroideos distribuidos en seis órdenes, 11 familias, 21 géneros y 28 especies. Se obtuvieron los registros nuevos para la CNE: Democrinus rawsonii y Atelecrinus balanoides en crinoideos. Astropecten alligator, Hymenaster modestus, Calyptraster personatus, Pteraster militarioides militarioides, Sclerasterias contorta en asteroideos. Con esta información se incrementan los registros de crinoideos y asteroideos (de profundidad mayor a 200 m) para los estados de Yucatán (16) y Quintana Roo (16).


Abstract Introduction: The species of the Crinoidea and Asteroidea classes are distributed in a wide variety of habitats in all oceans from the intertidal zone to great depths, there are few Mexican records in depths greater than 200 m, the few existing records date from historical documents in the specialized literature and the specimens are kept in foreign scientific collections. Objective: Contribute to the collection of information on the specimens kept in the Colección Nacional de Equinodermos (CNE) of Instituto de Ciencias del Mar y Limnología (ICML), UNAM and provide an inventory of the species of crinoids and asteroids that inhabit deep areas of the slope of the Yucatan Peninsula, Mexico. Methods: From 2005 to 2014, specimens of crinoids and asterioids were collected through four cruises in the B/O "Justo Sierra" BIOREPES 1 and 2 and COBERPES 2 and 6, shrimp net trawls were carried out at 80 sampling stations. Results: The taxonomic list includes 1146 specimens, of which 204 crinoids are of the order Comatulida, distributed in three families, three genera and three species and 942 asteroids distributed in six orders, 11 families, 21 genera and 28 species. New records were obtained for CNE: Democrinus rawsonii and Atelecrinus balanoides in crinoids. Astropecten alligator, Hymenaster modestus, Calyptraster personatus, Pteraster militarioides militarioides, Sclerasterias contorta in asteroids. With this information, the records of crinoids and asteroids (deeper than 200 m) increase for the states of Yucatan (16) and Quintana Roo (16).


Assuntos
Animais , Equinodermos/classificação , México
13.
PLoS One ; 19(3): e0298185, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38466680

RESUMO

Bioluminescence is the production of visible light by living organisms thanks to a chemical reaction, implying the oxidation of a substrate called luciferin catalyzed by an enzyme, the luciferase. The luminous brittle star Amphiura filiformis depends on coelenterazine (i.e., the most widespread luciferin in marine ecosystems) and a luciferase homologous to the cnidarian Renilla luciferase to produce blue flashes in the arm's spine. Only a few studies have focused on the ontogenic apparitions of bioluminescence in marine organisms. Like most ophiuroids, A. filiformis displays planktonic ophiopluteus larvae for which the ability to produce light was not investigated. This study aims to document the apparition of the luminous capabilities of this species during its ontogenic development, from the egg to settlement. Through biochemical assays, pharmacological stimulation, and Renilla-like luciferase immunohistological detection across different developing stages, we pointed out the emergence of the luminous capabilities after the ophiopluteus larval metamorphosis into a juvenile. In conclusion, we demonstrated that the larval pelagic stage of A. filiformis is not bioluminescent compared to juveniles and adults.


Assuntos
Equinodermos , Ecossistema , Animais , Organismos Aquáticos , Luciferases/química , Larva , Luciferinas
14.
Zootaxa ; 5418(2): 159-171, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38480365

RESUMO

A new species belonging to the ophiuroid genus Ophiomyxa is described from the Mallorca Channel seamount, in the western Mediterranean Sea. It can be distinguished from other Ophiomyxa species by the lack of interradial marginal plates, three arm spines, the presence of two thin, transparent and completely perforated dorsal arm plates on each arm segment, the separate heptagonal ventral arm plates, the disk integument full of transparent rounded scales with scattered perforated ossicles, and a characteristic coloration of the disk, which in the living specimen is brown with abundant scattered bright white spots. Molecular analyses based on cytochrome c Oxidase subunit I (DNA barcode) clearly support the assignment of the new species to Ophiomyxa. This discovery highlights the importance of the Mallorca Channel seamounts for the Mediterranean biodiversity conservation, as they seem to provide a suitable habitat for several invertebrate species, including recent descriptions of species and new Mediterranean records, which apparently have not established permanent populations along the closest continental margin.


Assuntos
Equinodermos , Ecossistema , Animais , Biodiversidade
15.
Zootaxa ; 5403(4): 479-487, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38480422

RESUMO

In Algeria, few studies have been carried on the Holothuriodea especially the family Cucumariidae Ludwig, 1894. A specimen was caught as bycatch from a commercial benthic trawler on the Mostaganem coast (northwest of Algeria). Based on a detailed study of the morphological, anatomical and endoskeletal characters, this specimen is confirmed to be Ocnus planci (Brandt, 1835). We report it herein as the first observation from the Algerian west coast. This species has been recorded several times in the Mediterranean sea. It is characterised by a calcareous ring, whose radial plates are longer than the interradial plates, the presence of buttons and perforated button plates of different sizes in the body wall, as well as various shapes of rosettes, baskets and nodules with small perforations.


Assuntos
Equinodermos , Pepinos-do-Mar , Animais
16.
Sci Rep ; 14(1): 4886, 2024 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418859

RESUMO

Morphologically cryptic and pseudo-cryptic species pose a challenge to taxonomic identification and assessments of species diversity and distributions. Such is the case for the sea cucumber Stichopus horrens, commonly confused with Stichopus monotuberculatus. Here, we used mitochondrial cytochrome oxidase subunit I (COI) and microsatellite markers to examine genetic diversity in Stichopus cf. horrens throughout the Philippine archipelago, to aid species identification and clarify species boundaries. Phylogenetic analysis reveals two recently diverged COI lineages (Clade A and Clade B; c. 1.35-2.54 Mya) corresponding to sequence records for specimens identified as S. monotuberculatus and S. horrens, respectively. Microsatellite markers reveal two significantly differentiated genotype clusters broadly concordant with COI lineages (Cluster 1, Cluster 2). A small proportion of individuals were identified as later-generation hybrids indicating limited contemporary gene flow between genotype clusters, thus confirming species boundaries. Morphological differences in papillae distribution and form are observed for the two species, however tack-like spicules from the dorsal papillae are not a reliable diagnostic character. An additional putative cryptic species was detected within Clade B-Cluster 2 specimens warranting further examination. We propose that these lineages revealed by COI and genotype data be referred to as Stichopus cf. horrens species complex.


Assuntos
Pepinos-do-Mar , Stichopus , Humanos , Animais , Pepinos-do-Mar/genética , Stichopus/genética , Equinodermos/genética , Filogenia , Repetições de Microssatélites/genética
17.
Nat Ecol Evol ; 8(4): 651-662, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38337049

RESUMO

Early Palaeozoic sites with soft-tissue preservation are predominantly found in Cambrian rocks and tend to capture past tropical and temperate ecosystems. In this study, we describe the diversity and preservation of the Cabrières Biota, a newly discovered Early Ordovician Lagerstätte from Montagne Noire, southern France. The Cabrières Biota showcases a diverse polar assemblage of both biomineralized and soft-bodied organisms predominantly preserved in iron oxides. Echinoderms are extremely scarce, while sponges and algae are abundantly represented. Non-biomineralized arthropod fragments are also preserved, along with faunal elements reminiscent of Cambrian Burgess Shale-type ecosystems, such as armoured lobopodians. The taxonomic diversity observed in the Cabrières Biota mixes Early Ordovician Lagerstätten taxa with Cambrian forms. By potentially being the closest Lagerstätte to the South Pole, the Cabrières Biota probably served as a biotic refuge amid the high-water temperatures of the Early Ordovician, and shows comparable ecological structuring to modern polar communities.


Assuntos
Artrópodes , Ecossistema , Animais , Fósseis , Biota , Equinodermos
18.
Biomolecules ; 14(2)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38397388

RESUMO

Three new bibenzochromenones named phanogracilins A-C (1-3) were isolated from the crinoid Phanogenia gracilis. The structure of 1 was established using X-ray crystallography as 5,5',6,6',8,8'-hexahydroxy-2,2'-dipropyl-4H,4'H-[7,9'-bibenzo[g]chromene]-4,4'-dione. This allowed us to assign reliably 2D NMR signals for compound 1 and subsequently for its isomer 2 that differed in the connecting position of two benzochromenone moieties (7,10' instead of 7,9'), and compound for 3 that differed in the length of the aliphatic chain of one of the fragments. Compound 4 was derived from 1 in alkaline conditions, and its structure was elucidated as 5,5',6',8,8'-pentahydroxy-2,2'-dipropyl-4H,4'H-[7,9'-bibenzo[g]chromene]-4,4',6,9-tetraone. Even though compounds 1-4 did not contain stereo centers, they possessed notable optical activity due to sterical hindrances, which limited the internal rotation of two benzochromenone fragments around C(7)-C(9'/10') bonds. Isolated bibenzochromenones 1-4 were tested for their antiradical, neuroprotective and antimicrobial activities. Compounds 1, 3 and 4 demonstrated significant antiradical properties towards ABTS radicals higher than the positive control trolox. Compounds 1 and 4 exhibited moderate neuroprotective activity, increasing the viability of rotenone-treated Neuro-2a cells at a concentration of 1 µM by 9.8% and 11.8%, respectively. Compounds 1 and 3 at concentrations from 25 to 100 µM dose-dependently inhibited the growth of Gram-positive bacteria S. aureus and yeast-like fungi C. albicans, and they also prevented the formation of their biofilms. Compounds 2 and 4 exhibited low antimicrobial activity.


Assuntos
Anti-Infecciosos , Staphylococcus aureus , Animais , Equinodermos , Anti-Infecciosos/farmacologia , Benzopiranos/química , Bactérias , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia
19.
J Comp Neurol ; 532(1): e25585, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38289190

RESUMO

Reproductive processes are regulated by a variety of neuropeptides in vertebrates and invertebrates. In starfish (phylum Echinodermata), relaxin-like gonad-stimulating peptide triggers oocyte maturation and spawning. However, little is known about other neuropeptides as potential regulators of reproduction in starfish. To address this issue, here, we used histology and immunohistochemistry to analyze the reproductive system of the starfish Asterias rubens at four stages of the seasonal reproductive cycle in male and female animals, investigating the expression of eight neuropeptides: the corticotropin-releasing hormone-type neuropeptide ArCRH, the calcitonin-type neuropeptide ArCT, the pedal peptide-type neuropeptides ArPPLN1b and ArPPLN2h, the vasopressin/ocytocin-type neuropeptide asterotocin, the gonadotropin-releasing hormone-type neuropeptide ArGnRH, and the somatostatin/allatostatin-C-type neuropeptides ArSS1 and ArSS2. The expression of five neuropeptides, ArCRH, ArCT, ArPPLN1b, ArPPLN2h, and asterotocin, was detected in the gonoducts and/or gonads. For example, extensive ArPPLN2h expression was revealed in the coelomic epithelial layer of the gonads throughout the seasonal reproductive cycle in both males and females. However, seasonal and/or sexual differences in the patterns of neuropeptide expression were also observed. Informed by these findings, the in vitro pharmacological effects of neuropeptides on gonad preparations from male and female starfish were investigated. This revealed that ArSS1 causes gonadal contraction and that ArPPLN2h causes gonadal relaxation, with both neuropeptides being more effective on ovaries than testes. Collectively, these findings indicate that multiple neuropeptide signaling systems are involved in the regulation of reproductive function in starfish, with some neuropeptides exerting excitatory or inhibitory effects on gonad contractility that may be physiologically relevant when gametes are expelled during spawning.


Assuntos
Asterias , Neuropeptídeos , Feminino , Masculino , Animais , Estrelas-do-Mar , Genitália , Equinodermos
20.
Genetics ; 227(1)2024 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-38262680

RESUMO

Echinobase (www.echinobase.org) is a model organism knowledgebase serving as a resource for the community that studies echinoderms, a phylum of marine invertebrates that includes sea urchins and sea stars. Echinoderms have been important experimental models for over 100 years and continue to make important contributions to environmental, evolutionary, and developmental studies, including research on developmental gene regulatory networks. As a centralized resource, Echinobase hosts genomes and collects functional genomic data, reagents, literature, and other information for the community. This third-generation site is based on the Xenbase knowledgebase design and utilizes gene-centric pages to minimize the time and effort required to access genomic information. Summary gene pages display gene symbols and names, functional data, links to the JBrowse genome browser, and orthology to other organisms and reagents, and tabs from the Summary gene page contain more detailed information concerning mRNAs, proteins, diseases, and protein-protein interactions. The gene pages also display 1:1 orthologs between the fully supported species Strongylocentrotus purpuratus (purple sea urchin), Lytechinus variegatus (green sea urchin), Patiria miniata (bat star), and Acanthaster planci (crown-of-thorns sea star). JBrowse tracks are available for visualization of functional genomic data from both fully supported species and the partially supported species Anneissia japonica (feather star), Asterias rubens (sugar star), and L. pictus (painted sea urchin). Echinobase serves a vital role by providing researchers with annotated genomes including orthology, functional genomic data aligned to the genomes, and curated reagents and data. The Echinoderm Anatomical Ontology provides a framework for standardizing developmental data across the phylum, and knowledgebase content is formatted to be findable, accessible, interoperable, and reusable by the research community.


Assuntos
Bases de Dados Genéticas , Equinodermos , Animais , Equinodermos/genética , Genoma , Genômica/métodos , Ouriços-do-Mar/genética , Bases de Conhecimento
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