Abstract Volume

Abstract Volume

ABSTRACT VOLUME August 11-16, 2019 1 2 Table of Contents Pages Acknowledgements……………………………………………………………………………………………...1 Abstracts Symposia and Contributed talks……………………….……………………………………………3-225 Poster Presentations…………………………………………………………………………………226-291 3 Venom Evolution of West African Cone Snails (Gastropoda: Conidae) Samuel Abalde*1, Manuel J. Tenorio2, Carlos M. L. Afonso3, and Rafael Zardoya1 1Museo Nacional de Ciencias Naturales (MNCN-CSIC), Departamento de Biodiversidad y Biologia Evolutiva 2Universidad de Cadiz, Departamento CMIM y Química Inorgánica – Instituto de Biomoléculas (INBIO) 3Universidade do Algarve, Centre of Marine Sciences (CCMAR) Cone snails form one of the most diverse families of marine animals, including more than 900 species classified into almost ninety different (sub)genera. Conids are well known for being active predators on worms, fishes, and even other snails. Cones are venomous gastropods, meaning that they use a sophisticated cocktail of hundreds of toxins, named conotoxins, to subdue their prey. Although this venom has been studied for decades, most of the effort has been focused on Indo-Pacific species. Thus far, Atlantic species have received little attention despite recent radiations have led to a hotspot of diversity in West Africa, with high levels of endemic species. In fact, the Atlantic Chelyconus ermineus is thought to represent an adaptation to piscivory independent from the Indo-Pacific species and is, therefore, key to understanding the basis of this diet specialization. We studied the transcriptomes of the venom gland of three individuals of C. ermineus. The venom repertoire of this species included more than 300 conotoxin precursors, which could be ascribed to 33 known and 22 new (unassigned) protein superfamilies, respectively. Most abundant superfamilies were T, W, O1, M, O2, and Z, accounting for 57% of all detected diversity. The different cysteine pattern of mature A contoxins in Indo-Pacific versus Atlantic cones suggest that piscivory in the cones from both oceans evolved through convergence. In addition, we are studying the evolution of conotoxin venoms in the radiations of vermivorous cones endemic to Senegal and Cabo Verde. 4 Setting The Foundations and Developing Tools for Studying the Regeneration of Complex Eyes in the Emerging Research Organism, Pomacea canaliculata (Gastropoda, Ampullariidae) Alice Accorsi*1, Eric Ross1, Melainia McClain2, Timothy Corbin2, and Alejandro Sánchez Alvarado1 1Howard Hughes Medical Institute, Stowers Institute for Medical Research, Kansas City, MO, USA 2Stowers Institute for Medical Research, Kansas City, MO, USA The freshwater snail Pomacea canaliculata is an emerging research organism in the field of developmental and regeneration biology. This mollusk has a direct embryonic development and possesses complex camera-type eyes, composed of a cornea, lens, retina and optic neuron, which can fully regenerate upon amputation. The adult P. canaliculata eye, therefore provides a unique opportunity to understand how a sensory organ is regenerated and functionally integrated with pre-existing adult tissues and to compare it to embryonic eye development. To introduce and develop the necessary molecular, cellular and genetic tools to mechanistically dissect the regeneration of a complex organ that is irreplaceable in all current model organisms, we have developed methods to keep this organism in captivity, to efficiently collect embryos at any developmental stage and culture them ex ovo to facilitate manipulations and live imaging. At present, genomic manipulations of embryos still require optimization, but we found that they can be successfully microinjected with exogenous mRNA. At the same time, we have also generated extensive embryonic development and regeneration transcriptomes and optimized in situ hybridization protocols to validate these molecular databases, to find markers for the various cell types present in the P. canaliculata eyes and to localize the expression of molecules driving the regeneration process. Altogether, these data represent the first few steps towards transforming P. canaliculata into a genetically tractable research organism for the study of animal regeneration that may eventually be adopted by others to study aspects of animal biology not readily accessible in current model systems. 5 Influence of Vitamin E on Shell Repair, Haemolymph Biochemical Parameters, Haemagglutination Potential and Ovo-tesist Activity of Giant African Land Snail (Archachatina marginata) After Shell Damage John Adesanya Abiona*1, Abiola Blessing Okunlola1, Nneka Sandra Obanya1, and Muhammed Okanlawon Onagbesan1 1P.M.B 2240, Alabata Road, Abeokuta. Department of Animal Physiology, Federal University of Agriclture, Abeokuta A study was conducted on the effect of Vitamin A on shell repair, haemolymph biochemical parameters, haemagglutination potential and ovo-tesist activity after shell damage. Forty (40) snails weighing between 150-200 g were randomly divided into four (4) treatments (with ten (10) replicate per treatment). At the commencement of the experiment, shells were damaged (length 3.5 cm and breadth 1.5 cm). The four treatments used in this study were: T1 (1g of vitamin A/kg of concentrate), T2, (2.5g of vitamin A/kg of concentrate) T3 (5g of vitamin A/kg of concentrate) and T4 (0g of vitamin A control). Parameters monitored were new shell growth, haemolymph biochemical parameter (Total protein, albumin, globulin and albumin globulin ratio), haemagglutination titre and ovo-testity activity. Result showed that rate of shell regrowth was not significantly different (P>0.05) between the control and those administered with various levels of Vitamin A after shell damage. Similarly, total protein, albumin, globulin and albumin-globulin ratio were not significantly affected by Vitamin A inclusion into the diet of snails. However, inclusion of Vitamin A into snail diet significantly (P<0.001) increased haemagglutination titre better than the control. Also, both Oogenic and spermatogenic activities were also positively influenced well than the control. However, the highest levels of activity were recorded at inclusion level of 5 and 2.5 g/kg of concentrate given. It can be concluded from this study that Vitamin A aid in the shell repair process, improve both immune status and reproductive function during period of shell injury in Giant African Land snail (A. marginata). 6 The Vanishing Mediterranean and the Assembly of A Novel Molluscan Fauna in the Levantine Basin Paolo G. Albano*1 1University of Vienna, Department of Palaeontology The Levantine basin in the easternmost Mediterranean Sea is well known for hosting hundreds of non-indigenous species introduced after the opening of the Suez Canal in 1869. An insufficiently recognized but even more dramatic phenomenon is the disappearance of native species. We here quantify this demise based on samples collected on intertidal and subtidal soft and hard substrates along the Israeli coast. We sampled during two seasons to capture any intra-annual variability and deployed a diverse array of techniques including grabbing, airlift sampling, scraping and handpicking. We used a fine sieve (0.5 mm) to retain small sized and juvenile individuals, deployed an intense identification effort including tracing the morphology of early ontogenetic stages, and considered the empty shells to reconstruct the baseline. The rocky intertidal was dominated by native species (61% and 73% in terms of richness and abundance, respectively) with limited seasonal variation and high spatial heterogeneity. The soft-substrate subtidal (10-40 m depth) showed a marked depth gradient, with assemblages down to 20 m with only 15-19% of native abundance which increased to 73-82% in deeper water, and a strong seasonality with spring dominated by native and autumn by non-indigenous species. Native species richness was below 50% year-around. The preliminary results for the rocky subtidal (10-25 m depth) suggest a similar pattern. Moreover, entire taxa such as Neogastropoda have become very rare (on rocky substrates they were just 4% of the diversity vs 18% in the death assemblage) while ectoparasites such as Pyramidellidae were 28% vs 16%, pointing at a complete reassembly of the local fauna. 7 Limited Growth and Hindered Reproduction Cause the Demise of Native Mollusks on the Israeli Mediterranean Shallow Shelf Paolo G. Albano*1, Jan Steger1, Zara Guifarro1, Bella S. Galil2, and Martin Zuschin1 1University of Vienna, Department of Palaeontology 2The Steinhardt Museum of Natural History, Israel National Center for Biodiversity Studies We here inspect the causes of the decline of native mollusks on the Israeli Mediterranean soft- substrate shallow shelf based on sampling along two transects off northern and southern Israel in autumn 2016 and spring 2017. We compared the living assemblages with a comprehensive literature-based checklist of Israeli mollusks filtered by appropriate substrate and depth, and the composition of the death assemblage collected with the living organisms. Our sampling intercepted only 24% of the historically recorded species. At individual sites, the living assemblage native richness is between 2.9% and 18.5% of the death assemblage native richness. The abundance of native species peaks in spring (80%, 934 individuals) but drops in autumn to only 15% (279 individuals, notwithstanding two additional replicates were collected) suggesting a mass mortality during summer. Abundant native species like Abra alba

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