Reproduction in the phylum Porifera: a synoptic overview

Les esponges són organismes importants des del punt de vista ecològic, evolutiu i biotecnològic: a) tenen un paper ecològic rellevant en moltes comunitats marines i participen en passos crucials en els cicles dels nutrients solubles i la matèria orgànica, b) els seus trets cel·lulars i genètics encara reflecteixen i proporcionen informació sobre la transició entre la condició unicel·lular i l'organització multicel·lular dels animals i c) les esponges i els seus simbionts són prometedores fonts de compostos amb interès per a la biomedicina i diversos processos industrials. Per aquestes raons, enginyers, químics, microbiòlegs, ecòlegs, genètics i biòlegs evolutius, generalment amb escassa formació en esponges, necessiten apropar-se professionalment a la complexa i distintiva biologia reproductiva d'aquest grup. Aquest repàs sinòptic, que no pretén ser una revisió total, intenta respondre les necessitats d'aquesta audiència heterogènia. Es resumeix el procés general de reproducció sexual i asexual en el fílum, combinant dades tant ecològiques com citològiques. Es fa èmfasi en els processos d'espermatogènesi, oogènesi i fecundació. A més de l'esquematització dels processos generals, es mencionen les excepcions més destacables, així com els punts febles en el coneixement actual amb intenció de promoure investigacions futures.Sponges (phylum Porifera) are important organisms from an ecological, evolutionary and biotechnological point of view: i) they play relevant ecological roles in many marine communities and participate in crucial steps of the cycle of dissolved nutrients and organic matter; ii) their cellular and genetic traits still reflect and inform about the ancient transition between the unicellular condition and the multicellular organization of animals, and iii) they and/or their symbionts are a promising source of compounds of interest in biomedicine and some industrial processes. For these reasons, engineers, chemists, microbiologists, general ecologists, geneticists, and evolutionary biologists, who usually have little expertise with sponges, need to professionally approach the complex, unique reproductive biology of this group. This synoptic overview, which does not intend to be a comprehensive review, attempts to fulfill the needs of such a heterogeneous potential audience. It summarizes the general process of sexual and asexual reproduction in the phylum, combining both ecological and cytological data. Emphasis is made on the processes of spermatogenesis, oogenesis, and fertilization. In addition to outlining general processes, a brief mention of exceptions, recent relevant findings and the weak points in current knowledge is provided with the aim of encouraging future research

Monitorización de emergencia de víctimas de catástrofes. Proyecto MERIS

La gestión de una catástrofe requiere acciones inmediatas y bien planificadas. Las personas que sufren traumas y no mueren de inmediato tienen grandes posibilidades de sobrevivir, si reciben una pronta atención médica especializada; pasado ese breve plazo, la mortalidad crece notablemente. El proyecto MERIS descrito en este artículo pretende optimizar la asignación de recursos humanos y técnicos durante la atención prehospitalaria en situaciones de emergencia, a través de un dispositivo electrónico que permita al personal de emergencias el acceso a la información en tiempo real sobre el estado de todas las víctimas recuperables.Peer Reviewe

Optimizing preservation protocols to extract high-quality RNA from different tissues of echinoderms for Next Generation Sequencing

Transcriptomic information provides fundamental insights into biological processes. Extraction of quality RNA is a challenging step, and preservation and extraction protocols need to be adjusted in many cases. Our objectives were to optimize preservation protocols for isolation of high‐quality RNA from diverse echinoderm tissues and to compare the utility of parameters as absorbance ratios and RIN values to assess RNA quality. Three different tissues (gonad, oesophagus and coelomocytes) were selected from the sea urchin Arbacia lixula. Solid tissues were flash‐frozen and stored at −80 °C until processed. Four preservation treatments were applied to coelomocytes: flash freezing and storage at −80 °C, RNAlater and storage at −20 °C, preservation in TRIzol reagent and storage at −80 °C and direct extraction with TRIzol from fresh cells. Extractions of total RNA were performed with a modified TRIzol protocol for all tissues. Our results showed high values of RNA quantity and quality for all tissues, showing nonsignificant differences among them. However, while flash freezing was effective for solid tissues, it was inadequate for coelomocytes because of the low quality of the RNA extractions. Coelomocytes preserved in RNAlater displayed large variability in RNA integrity and insufficient RNA amount for further isolation of mRNA. TRIzol was the most efficient system for stabilizing RNA which resulted on high RNA quality and quantity. We did not detect correlation between absorbance ratios and RNA integrity. The best strategies for assessing RNA integrity was the visualization of 18S rRNA and 28S rRNA bands in agarose gels and estimation of RIN values with Agilent Bioanalyzer chips

Rapid prototyping for multi-application sensor networking

Jorge Portilla, Teresa Riesgo, Ana Abril, and Angel De Castro, “Rapid prototyping for multi-application sensor networking,” Spie Newsroom, Spie, (2007). Copyright © 2015 SPIE Society of Photo‑Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited.Developing integrated hardware interfaces for different actuators allows rapid and easy integration into existing wireless network

Integrated hardware interfaces for modular sensor networks

Portilla, J., de Castro, A., Abril, A., Riesgo, T., “Integrated hardware interfaces for modular sensor networks”, Proceedings of SPIE - The International Society for Optical Engineering”, 6590, 9, 2007. Copyright 2007. Society of Photo‑Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited.Sensor networks have reached a great relevance during the last years. The idea is to use a large number of nodes measuring different physical parameters in several environments, which implies different research challenges (low power consumption, communication protocols, platform hardware design, etc). There is a tendency to use modular hardware nodes in order to make easier rapid prototyping as well as to be able to redesign faster and reuse part of the hardware modules. One of the main obstacles for rapid prototyping is that sensors present heterogeneous interfaces. In this paper, a VHDL library for sensors/actuators interfaces is proposed. The purpose is to have a set of different sensor interfaces that include the most common in the sensors/actuators world, enabling the rapid connection to a new sensor/actuator. Moreover, the concept presented here may be used for new interfaces that can be easily developed. The VHDL implementation is independent of the final platform (any FPGA or ASIC) in order to minimize redesign effort and make easier rapid prototyping. The interfaces are installed in a UPM platform for sensor networks

A new species of Isodictya (Porifera: Poecilosclerida) from the Southern Ocean

We discovered a new species of Porifera belonging to the genus Isodictya Bowerbank, 1864 during cruises aboard R/V Hesperides in Antarctica. Collected samples are mostly part of the surveys of the Spanish project BENTART whose main objective has been to study the benthic communities inhabiting sea bottoms of Livingston and Deception Island in the South Shetlands archipelago and the Antarctic Peninsula. Isodictya filiformis sp. nov., described here, is characterized by its fragile and thin morphology (very different from other known species in the area) and by having microxeas as additional microscleres. Three specimens were collected from Marguerite Bay, Low Island and Deception Island (Antarctic Peninsula) and one specimen at Peter I Island (Bellingshausen Sea). Its presence in Peter Island is quite relevant as this location is 390 km away from the nearest coast in the Bellingshausen Sea, an area that has scarcely been investigated in the past. However, results from the Bentart 03 Expedition seem to indicate that Peter I Island has a wide variety of benthic organisms, in contrast to the deep adjacent areas of Bellingshausen Sea. Apart from the morphological analyses, we place the new Isodictya species within its phylogenetic context using two nuclear markers (18S rDNA and 28S rDNA) and provide some information about the ecological preferences of the new speciesPostprint1,44

Evolutionary origins of sensation in metazoans: functional evidence for a new sensory organ in sponges

Background: One of the hallmarks of multicellular organisms is the ability of their cells to trigger responses to the environment in a coordinated manner. In recent years primary cilia have been shown to be present as 'antennae' on almost all animal cells, and are involved in cell-to-cell signaling in development and tissue homeostasis; how this sophisticated sensory system arose has been little-studied and its evolution is key to understanding how sensation arose in the Animal Kingdom. Sponges (Porifera), one of the earliest evolving phyla, lack conventional muscles and nerves and yet sense and respond to changes in their fluid environment. Here we demonstrate the presence of non-motile cilia in sponges and studied their role as flow sensors. Results: Demosponges excrete wastes from their body with a stereotypic series of whole-body contractions using a structure called the osculum to regulate the water-flow through the body. In this study we show that short cilia line the inner epithelium of the sponge osculum. Ultrastructure of the cilia shows an absence of a central pair of microtubules and high speed imaging shows they are non-motile, suggesting they are not involved in generating flow. In other animals non-motile, 'primary', cilia are involved in sensation. Here we show that molecules known to block cationic ion channels in primary cilia and which inhibit sensory function in other organisms reduce or eliminate sponge contractions. Removal of the cilia using chloral hydrate, or removal of the whole osculum, also stops the contractions; in all instances the effect is reversible, suggesting that the cilia are involved in sensation. An analysis of sponge transcriptomes shows the presence of several transient receptor potential (TRP) channels including PKD channels known to be involved in sensing changes in flow in other animals. Together these data suggest that cilia in sponge oscula are involved in flow sensation and coordination of simple behaviour. Conclusions: This is the first evidence of arrays of non-motile cilia in sponge oscula. Our findings provide support for the hypothesis that the cilia are sensory, and if true, the osculum may be considered a sensory organ that is used to coordinate whole animal responses in sponges. Arrays of primary cilia like these could represent the first step in the evolution of sensory and coordination systems in metazoans. © 2014 Ludeman et al.; licensee BioMed Central Ltd

On the way to specificity ‐ Microbiome reflects sponge genetic cluster primarily in highly structured populations

Most animals, including sponges (Porifera), have species-specific microbiomes. Which genetic or environmental factors play major roles structuring the microbial community at the intraspecific level in sponges is, however, largely unknown. In this study, we tested whether geographic location or genetic structure of conspecific sponges influences their microbial assembly. For that, we used three sponge species with different rates of gene flow, and collected samples along their entire distribution range (two from the Mediterranean and one from the Southern Ocean) yielding a total of 393 samples. These three sponge species have been previously analysed by microsatellites or single nucleotide polymorphisms, and here we investigate their microbiomes by amplicon sequencing of the microbial 16S rRNA gene. The sponge Petrosia ficiformis, with highly isolated populations (low gene flow), showed a stronger influence of the host genetic distance on the microbial composition than the spatial distance. Host-specificity was therefore detected at the genotypic level, with individuals belonging to the same host genetic cluster harbouring more similar microbiomes than distant ones. On the contrary, the microbiome of Ircinia fasciculata and Dendrilla antarctica - both with weak population structure (high gene flow) - seemed influenced by location rather than by host genetic distance. Our results suggest that in sponge species with high population structure, the host genetic cluster influence the microbial community more than the geographic location

Optimization of fourteen microsatellite loci in a Mediterranean demosponge subjected to population decimation, Ircinia fasciculata

The recovery potential of decimated populations of sponges will largely hinge on their populations' size retrieval and their connectivity with conspecifics in unaffected locations. Here, we report on the development of microsatellite markers for estimation of the population connectivity and bottleneck and inbreeding signals in a Mediterranean sponge suffering from disease outbreaks, Ircinia fasciculata. From the 220,876 sequences obtained by genomic pyrosequencing, we isolated 14 polymorphic microsatellite loci and assessed the allelic variation of loci in 24 individuals from 2 populations in the Northwestern Mediterranean. The allele number per locus ranged from 3 to 11, observed heterozygosity from 0.68 to 0.73, and expected heterozygosity from 0.667 to 0.68. No significant linkage disequilibrium between pairs of loci was detected. The 14 markers developed here will be valuable tools for conservation strategies across the distributional range of this species allowing the detection of populations with large genetic diversity loss and high levels of inbreeding

A new member of the genus Antarctonemertes (Hoplonemertea, Nemertea) from Antarctic waters

11 p.The phylum Nemertea is an important component of the benthic ecosystems of the Southern Ocean, but its biodiversity is still relatively poorly known in Antarctic waters. There are few common and well-known nemertean species occurring in the shallow Antarctic waters, and these include the congeneric Antarctonemertes valida (Bürger, 1893) and Antarctonemertes riesgoae Taboada et al., 2013, two relatively small brooding hoplonemerteans whose females lay eggs inside cocoons. A third Antarctic member of the genus, Antarctonemertes belgica (Bürger, 1904), was reported only in the original descrip-tion. Here we document the existence of a fourth Antarctic member of the genus Antarctonemertes originally described as Tetrastemma unilineatum Joubin, 1910. Our phylogenetic analysis resulted into the placement of the new Antarctonemertes in a robustly supported clade ?Antarctic Antarctonemertes? containing the other two congeneric Antarctic species (A. valida and A. riesgoae), and pairwise COI molecular distances between the three species ranged from 5.2 to 6.2% (p distance). The analysis of 104 COI sequences of the three species showed star-like haplotype networks, as in other studies on Antarctic invertebrates. Antarctonemertes unilineata comb. nov. is similar in shape to its Antarctic congeneric relatives and its most prominent morphological character is a dorsal mid-longitudinal band present along the body. We also document the pres-ence of a cocoon built by females of A. unilineata comb. nov., a character shared with its Antarctic congeners analysed here. Although the four Antarctic Antarctonemertes species appear to overlap their distribution, A. riesgoae, A. valida and A. belgica appear in sympatry in the West Antarctic shores while A. unilineata comb. nov. has been mainly found in the East Antarctic shores and sub-Antarctic Islands.DistantcomAustralian Antarctic Divisio