Search

Shell color shows broad variation within mollusc species and despite information on the genetic pathways involved in shell construction and color has recently increased, more studies are needed to understand its genetic architecture. The common cockle ( Cerastoderma edule) is a valuable species from ecological and commercial perspectives which shows important variation in shell color across Northeast Atlantic. In this study, we constructed a high-density genetic map, as a tool for screening common cockle genome, which was applied to ascertain the genetic basis of color variation in the species. The consensus genetic map comprised 19 linkage groups (LGs) in accordance with the cockle karyotype (2n = 38) and spanned 1073 cM, including 730 markers per LG and an inter-marker distance of 0.13 cM. Five full-sib families showing segregation for several color-associated traits were used for a genome-wide association study and a major QTL on chromosome 13 associated to different color-traits was detected. Mining on this genomic region revealed several candidate genes related to shell construction and color. A genomic region previously reported associated with divergent selection in cockle distribution overlapped with this QTL suggesting its putative role on adaptation Interreg Atlantic Area | Ref. EAPA_458/2016 Ministerio de Economía, Industria y Competitividad | Ref. BES2016/078166 Roslin Institute | Ref. BBS/E/D/20002172 Roslin Institute | Ref. BBS/E/D/30002275 Roslin Institute | Ref. BBS/E/D/10002070

The presence of shell bands is common in gastropods. Both the marine snails Littorina fabalis and Lttorina saxatilis are polymorphic for this trait. Such polymorphism would be expected to be lost by the action of genetic drift or directional selection, but it appears to be widespread at relatively constant frequencies. This suggests it is maintained by balancing selection on the trait or on a genetically linked trait. Using long time series of empirical data, we compared potential effects of genetic drift and negative frequency-dependent selection (NFDS) in the two species. The contribution of genetic drift to changes in the frequency of bands in L. fabalis was estimated using the effective population size estimated from microsatellite data, while the effect of genetic drift in L. saxatilis was derived from previously published study. Frequency-dependent selection was assessed by comparing the cross-product estimator of fitness with the frequency of the polymorphism across years using a regression analysis. Both studied species showed patterns of NFDS. In addition, in L. fabalis, contributions from genetic drift could explain some of the changes in banding frequency. Overdominance and heterogeneous selection did not fit well to our data. The possible biological explanations resulting in the maintenance of the banding polymorphism are discussed. Ministerio de Economía, Industria y Competitividad | Ref. CGL2016‐75904‐C2‐1‐P Xunta de Galicia | Ref. ED431C 2016-037

17 Pág. Departamento de ​Mejora Genética Animal (INIA), Genomic relationship matrices are used to obtain genomic inbreeding coefficients. However, there are several methodologies to compute these matrices and there is still an unresolved debate on which one provides the best estimate of inbreeding. In this study, we investigated measures of inbreeding obtained from five genomic matrices, including the Nejati-Javaremi allelic relationship matrix (FNEJ), the Li and Horvitz matrix based on excess of homozygosity (FL&H), and the VanRaden (methods 1, FVR1, and 2, FVR2) and Yang (FYAN) genomic relationship matrices. We derived expectations for each inbreeding coefficient, assuming a single locus model, and used these expectations to explain the patterns of the coefficients that were computed from thousands of single nucleotide polymorphism genotypes in a population of Iberian pigs., This work was carried out with funding from the Ministerio de Ciencia e Innovación, Spain (CGL2016-75904-C2, PID2020-114426GB-C22), the European Commission Horizon 2020 (H2020) Framework Programme through grant agreement no 727315 MedAID project (Mediterranean Aquaculture Integrated Development), Xunta de Galicia (ED431C 2020-05) and Fondos FEDER.R. Pong-Wong is funded by the European Union’s Horizon 2020 research and innovation program under the Grant Agreement n°772787 (SMARTER) and the Biotechnology and Biological Sciences Research Council through Institute Strategic Programme Grant funding (BBS/E/D/30002275)

21 Pág. Departamento de Mejora Genética Animal, Pollution and other anthropogenic effects have driven a decrease in Atlantic salmon (Salmo salar) in the Iberian Peninsula. The restocking effort carried out in the 1980s, with salmon from northern latitudes with the aim of mitigating the decline of native populations, failed, probably due to the deficiency in adaptation of foreign salmon from northern Europe to the warm waters of the Iberian Peninsula. This result would imply that the Iberian populations of Atlantic salmon have experienced local adaptation in their past evolutionary history, as has been described for other populations of this species and other salmonids. Local adaptation can occur by divergent selections between environments, favoring the fixation of alleles that increase the fitness of a population in the environment it inhabits relative to other alleles favored in another population. In this work, we compared the genomes of different populations from the Iberian Peninsula (Atlantic and Cantabric basins) and Scotland in order to provide tentative evidence of candidate SNPs responsible for the adaptive differences between populations, which may explain the failures of restocking carried out during the 1980s. For this purpose, the samples were genotyped with a 220,000 high-density SNP array (Affymetrix) specific to Atlantic salmon. Our results revealed potential evidence of local adaptation for North Spanish and Scottish populations. As expected, most differences concerned the comparison of the Iberian Peninsula with Scotland, although there were also differences between Atlantic and Cantabric populations. A high proportion of the genes identified are related to development and cellular metabolism, DNA transcription and anatomical structure. A particular SNP was identified within the NADP-dependent malic enzyme-2 (mMEP-2*), previously reported by independent studies as a candidate for local adaptation in salmon from the Iberian Peninsula. Interestingly, the corresponding SNP within the mMEP-2* region was consistent with a genomic pattern of divergent selection., This work was funded by the Ministerio de Economía y Competitividad, Spain (grant RZ2A12-00011-CO2-01/02) and has received financial support from Xunta de Galicia (Grupo de Referencia Competitiva, ED431C 2020/05, Centro Singular de Investigación de Galicia accreditation 2019–2022) and the European Union (European Regional Development Fund—ERD

A fishery’s structure and connectivity are priors to its effective management. A successful description of such processes depends on both the sampling design and the choice of adequate genetic markers. EST markers are perfusing the studies of marine metapopulations and are believed to provide access to functional polymorphisms. However, the assumed adaptive role of outlier EST loci might not be generalizable. EST-microsatellites represent the upper polymorphic boundary in these regions because of their high mutation rate. We have subclassified the polymorphisms of EST-microsatellites to assess their structural contribution in the European hake, a paradigmatic and highly mobile marine species (HMMS). Because of the counterbalanced forces between directional markers (15%) and balanced markers (23%), the whole marker set offers the same structural situation as the one observed with neutral markers (62%), i.e., k = 2 gene pools. In contrast to outlier EST- microsatellites, neutral EST subsets allow one to measure crucial population phenomena for fisheries’ management. The high inter-population divergence of outlier EST-microsatellites is compatible with drifted post-selection genomic regions rather than with ongoing local selective pressures. The structural scenario in hake is explainable by a limited gene flow across the Almería-Oran Front (AOF) and by the within-basin IBD pattern of connectivity plus drift-related demographic events. This study highlights how polymorphic properties of EST-microsatellite types can be useful to address mutually excluding research tasks in fisheries, i.e., to address its evolutionary history (directional markers or FAPS: Fossil Adaptive Polymorphic Systems); to delineate management units (neutral markers or NAPS: Non Adaptive Polymorphic Systems); or to ensure sustainability (balanced markers or APS: Adaptive Polymorphic Systems). Xunta de Galicia | Ref. ED481A-2017/362

Explicitly accounting for phenotypic differentiation together with environmental heterogeneity is crucial to understand the evolutionary dynamics in hybrid zones. Species showing intra-specific variation in phenotypic traits that meet across environmentally heterogeneous regions constitute excellent natural settings to study the role of phenotypic differentiation and environmental factors in shaping the spatial extent and patterns of admixture in hybrid zones. We studied three environmentally distinct contact zones where morphologically and reproductively divergent subspecies of Salamandra salamandra co-occur: the pueriparous S. s. bernardezi that is mostly parapatric to its three larviparous subspecies neighbours. We used a landscape genetics framework to: (i) characterise the spatial location and extent of each contact zone; (ii) assess patterns of introgression and hybridization between subspecies pairs; and (iii) examine the role of environmental heterogeneity in the evolutionary dynamics of hybrid zones. We found high levels of introgression between parity modes, and between distinct phenotypes, thus demonstrating the evolution to pueriparity alone or morphological differentiation do not lead to reproductive isolation between these highly divergent S. salamandra morphotypes. However, we detected substantial variation in patterns of hybridization across contact zones, being lower in the contact zone located on a topographically complex area. We highlight the importance of accounting for spatial environmental heterogeneity when studying evolutionary dynamics of hybrid zones., This work was supported by National Funds through FCT – Foundation for Science and Technology (SALOMICS: PTDC/BIA-EVL/28475/2017); the authors also acknowledge funding from other FCT projects and FEDER funds through the Operational Programme for Competitiveness Factors – COMPETE (EVOVIV: PTDC/BIA-EVF/3036/2012; FCOMP-01-0124-FEDER-028325 and UIDB/500027/2020); and by National/FEDER funds through Ministerio de Economía y Competitividad (CGL2012-40246-C02-02). G.V.-A., A.L. and P.T. were supported by FCT (IF/01425/2014 and CEECIND/00937/2018, PD/BD/106060/2015, DL57/2016/CP1440/CT0008, respectively).

17 pages, 6 figures, 6 tables, supplementary information https://doi.org/10.1038/s41598-021-85008-9, Hakes of the genus Merluccius include 11 valid species as well a number of rare morphotypes suspected to be “cryptic species”. Concatenated nucDNA ITS1-rDNA and mtDNA cyt b sequences plus nested ITS1Nes sequences allowed to ascribe 14 specimens of nine rare morphotypes from the South Pacific and the South Atlantic to the phylogenetic backbone of this genus. Bayesian analyses pointed to M. bilinearis and M. albidus as the oldest species of the genus and the New World cluster, respectively. The phylogenetic status of M. angustimanus from the upper Gulf of California suggests its hybrid origin between M. gayi and M. productus from about 0.25 MYA, although an ever since confinement of a subset of those species cannot be ruled out. The molecular phylodiagnostic test suggests a common origin of all rare morphotypes and the absence of cryptic hake species in the Southern Cone. The molecular background of the morphotypes distributed between the Western Pacific South of New Zealand and the western Atlantic South of Argentina is compatible with their hybrid origin between M. gayi and both, M. australis or M. hubbsi, respectively, The Regional Government of Xunta de Galicia supported the M. F-M.’s Ph. D. grant (ED481A-2017/362). This research was partially supported with the project LETSHAKE (AGL2013-4846-R) co-funded by MINECO (Ministerio Español de Economía y Competitividad) and EU-FEDER to M.P. as well as with grant (IN607B 2018/14) to M. P. from Xunta de Galicia-Axencia Galega de Innovación. This work was also partly funded with grants from “Consellería de Educación e Ordenación Universitaria Xunta de Galicia (Galician Regional Government) cofunding from the European Regional Development Fund (ERDF) in the framework of the Operational Program Galicia 2014–2020 (CIM-UVIGO), “A way to build Europe”., With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI)

CRUE-CSIC agreement; Springer Nature; Agencia Estatal de Investigación, Spain [PCIN-2016-120, PCIN-2016-063]; Fundacao para a Ciencia e Tecnologia, Portugal [BIODIVERSA/0005/2015, BIODIVERSA/0006/2015]; Agence Nationale de la Recherche, France [ANR-16-EBI3-0006-01, ANR-16-EBI3-0006-02]; AA is supported by a FPU fellowship (Ref. FPU2016-04258, Spanish Ministry of Science, Innovation and Universities). KG is supported by a fellowship from the Severo Ochoa PhD program (Ref. PA-18-PF-BP17-184, Principado de Asturias). GM is supported by post-doctoral contracts from projects PERCEBES (PCIN-2016-063) and MARISCO (CTM2014-51935-R, Spanish Ministerio de Economía y Competitividad)., Aguión, A., Cruz, T., Acuña, J.L., Broudin, C., Castro, J.J., Davoult, D., Dubert, J., Fernandes, J.N., Geiger, K.J., Jacinto, D., Mateus, D., Muñiz, C., Nolasco, R., Perrier, L., Queiroga, H., Román, S., Silva, T., Thiébaut, E., Vázquez, E., Macho, G.

The stalked barnacle Pollicipes pollicipes inhabits rocky shores from the Atlantic coasts of Brittany (France) to Senegal. Because of the culinary traditions of southern Europe, stalked barnacles represent an important target species for local fisheries on the Iberian Peninsula. To manage this fishery sustainably, it is therefore important to assess the dynamics of local populations over the Iberian coast, and how they are interconnected at a wider scale using finely tuned genetic markers. In this work, a new enriched library of GT microsatellites for P. pollicipes was prepared and sequenced using Ion Torrent™ Next Gen-Sequencing Technology. 1,423 adults and juveniles were sampled in 15 localities of three geographic regions: southern Portugal, Galicia and Asturias (both in northern Spain). Twenty polymorphic loci arranged in five multiplex PCRs were then tested and validated as new molecular tools to address the spatial and temporal genetic patterns of P. pollicipes. Our results revealed high genetic diversity among adults. However, juveniles were genetically more structured than their adult counterparts, which alternatively displayed much more connectivity among the three studied regions. The lack of spatial genetic heterogeneity in adults may be due to the overlapping of several generations of settlers coming from different geographic origins, which mainly depends on the orientation of residual currents along the coast during reproduction. The genetic differentiation of juveniles may indeed be congruent with Iberian Peninsula hydrodynamics, which can produce chaotic genetic patchiness (CGP) at small temporal scales due to sweepstake reproductive success, collective dispersal and/or self-recruitment. Remarkably, most of the genetic heterogeneity of juveniles found in this work was located in Galicia, which could represent an admixture between distinct metapopulations or an old refuge for the most northern populations. To conclude, high genetic variation in P. pollicipes can lead to the false impression of population panmixia at the Iberian scale by masking more restricted and current-driven larval exchanges between regions. This possibility should be taken into consideration for further specific management and conservation plans for the species over the Iberian Peninsula. Ministerio de Economía, Industria y Competitividad | Ref. PCIN-2016-120 Ministerio de Economía, Industria y Competitividad | Ref. PCIN-2016-063 Agencia Estatal de Investigación | Ref. PID2019-108481RB-I00 Fundação para a Ciência e Tecnologia | Ref. UIDB/04292/2020 Xunta de Galicia | Ref. ED431C 2020-05 Ministerio de Ciencia, Innovación y Universidades | Ref. FPU2016-04258 Principado de Asturias | Ref. PA-18-PF-BP17-184 Ministerio de Economía y Competitividad | Ref. CTM2014-51935-R NASA | Ref. 80NSSC20K0074

DNA metabarcoding has proven to be an accessible, cost-effective, and non-invasive tool for dietary analysis of predators in situ. Although DNA metabarcoding provides numerous benefits in characterizing diet—such as detecting prey animals that are difficult to visually identify—this method has seen limited application in amphibian species. Here, we used DNA metabarcoding to characterize the diet of fire salamanders (Salamandra salamandra) (Linnaeus, 1758) in three distinct regions across the northwestern Iberian Peninsula. To test the efficiency of COI-based metabarcoding in determining salamanders’ diet diversity, we compared our COI-based results with results from traditional diet studies from neighboring and distant populations, as well as with recent findings obtained in a DNA metabarcoding study using 18S. Two COI primers were used in combination to investigate the potential impact of primer bias in prey detection. Our COI metabarcoding approach increased taxonomic resolution and supported a generalist diet in S. salamandra. Between primers, there were no significant differences in the diversity and richness of prey detected. We observed differences in the prevalence of prey identified between sampling regions both in our study and in other studies of S. salamandra diet. This COI metabarcoding study provides recommendations and resources for subsequent research using DNA metabarcoding to study amphibian diets. Fundação para a Ciência e a Tecnologia | Ref. PTDC/BIA-EVL/28475/2017 Fundação para a Ciência e a Tecnologia | Ref. PTDC/BIA-CBI/2278/2020 Fundação para a Ciência e a Tecnologia | Ref. 2020.02547.CEECIND Fundação para a Ciência e a Tecnologia | Ref. CEECIND/00937/2018 Agencia Estatal de Investigación | Ref. RYC-2019-026959-I Norte Portugal Regional Operational Programme | Ref. NORTE-01-0246-FEDER-000063

96 p. Los trabajos incluidos en esta Tesis Doctoral proporcionan una visión global de la utilidad de las herramientas moleculares actuales de secuenciación y genotipado a nivel genómico para estudiar la arquitectura genética subyacente a los caracteres de rendimiento quesero y las propiedades de coagulación de la leche, caracteres de interés económico en el ganado ovino lechero. Además, esta Tesis Doctoral evalúa la utilidad práctica de los resultados obtenidos en estos estudios y su posible impacto en los programas de selección actuales aplicados en el ganado ovino lechero.

El valor nutricional de la carne está determinado por el contenido de nutrientes necesarios para el cuerpo humano. Estos son; vitaminas, minerales, grasas, agua, carbohidratos y proteínas. La carne como producto proteico, está determinada por el balance de la composición de aminoácidos (aa). Los objetivos del presente estudio fueron 1: Poner a punto y cuantificar, mediante cromatografía de altas presiones de fase reversa (HPLC), el perfil de aminoácidos esenciales y no esenciales en la carne de vacuno; y 2: evaluar las diferencias en el perfil de aminoácidos esenciales y no esenciales de 2 razas de ganado vacuno. Fueron utilizados un total de 27 animales, 15 animales fueron de la raza bovina Wagyu (WA) y 12 del cruce de esta con Aberdeen-Angus, a lo que se llamó Wangus (WN). Al momento del sacrificio los animales tenían entre 22 y 47 meses de edad. Se analizó el músculo Longissimus dorsi. Los pasos para la determinación de aminoácidos fueron: hidrólisis ácida con HCL 6 N a 110 °C durante 24 horas; derivatización precolumna con 6 – aminoquinolyl – N - hydroxysuccinimidyl carbamate; cromatografía de altas presiones de fase reversa y detección por fluorescencia a 250 y 395 nanómetros (nm). Para la determinación del triptófano se llevó a cabo otro procedimiento: hidrólisis con NaOH 6N a 100 °C durante 4 horas, cromatografía de altas presiones de fase reversa y detección por espectofotometría a 280 nm. Los resultados generales muestran que no existen diferencias significativas entre ambas razas (P=0.54). La cantidad de prolina e histidina fue mayor para la raza WA y la cantidad de tirosina fue mayor para la raza WN (P

Uno de los motores de la evolución es el potencial adaptativo de las especies. La capacidad de adaptación a nuevas condiciones ambientales es de fundamental importancia, entre otros, en procesos de: a) especiación ecológica que dan lugar a la formación de nuevas especies; b) adaptación a nuevas condiciones originadas por cambios drásticos en los ecosistemas como resultado de, por ejemplo, el cambio climático y c) invasión de nuevos ecosistemas que pueden alterar la estabilidad de los mismos. Llegar a comprender estos tres procesos y sus interacciones es crucial para poder evaluar los riesgos frente a la conservación de la biodiversidad. En las costas gallegas existen diferentes especies de gasterópodos de la familia Muricidae, todas ellas depredadoras de moluscos bivalvos. La especie autóctona, Nucella lapillus, presenta un especial interés, tanto a nivel morfológico como cromosómico. Determinar la variabilidad genética de esta especie autóctona, en las diferentes poblaciones, nos ayudará a mejorar nuestro conocimiento sobre los tres procesos mencionados anteriormente. Es común que especies de gasterópodos marinos con baja capacidad dispersiva (ej. con desarrollo directo) presenten adaptaciones a diferentes microhábitats dentro de la misma zona intermareal. Esto, es debido a las diferentes presiones selectivas presentes en estos microhábitats (Galindo y Grahame, 2015). Nucella lapillus es una de las especies que presenta variabilidad fenotípica potencialmente adaptativa. Además de este polimorfismo fenotípico, N. lapillus es una de las pocas especies, por no decir la única, que presenta un polimorfismo cromosómico Robertsoniano (2n = 26-36) (Bantock y Cockayne, 1975) y, por lo tanto, determinar si éste constituye una barrera al flujo génico y/o si está relacionado con algún proceso adaptativo también representa un objetivo importante puesto que podría relacionar la evolución del genoma con mecanismos ecológicos (ej. adaptación) y/o la aparición de barreras reproductivas. La variación genética detectada en las diferentes poblaciones y las diferencias observadas en función de su grado de dispersión nos permitirá determinar la futura dinámica de dichas poblaciones en las costas gallegas y, por lo tanto, será importante para poder tomar las medidas pertinentes desde el punto de vista de la conservación de la biodiversidad y la estabilidad del ecosistema. Un dos motores da evolución é o potencial adaptativo das especies. A capacidade de adaptación a novas condicións ambientais é de fundamental importancia, entre outros, en procesos de: a) especiación ecolóxica que dan lugar á formación de novas especies; b) adaptación a novas condicións orixinadas por cambios drásticos nos ecosistemas como resultado de, por exemplo, o cambio climático e c) invasión de novos ecosistemas que poden alterar a estabilidade dos mesmos. Chegar a comprender estes tres procesos e as súas interacións é crucial para poder avaliar os riscos fronte á conservación da biodiversidade. Nas costas galegas existen diferentes especies de gasterópodos da familia Muricidae, todas elas predadoras de moluscos bivalvos. A especie autóctona, Nucella lapillus, presenta un especial interese, tanto a nivel morfolóxico como cromosómico. Determinar a variabilidade xenética desta especie autóctona, nas diferentes poboacións, axudaranos a mellorar o noso coñecemento sobre os tres procesos mencionados anteriormente. É común que especies de gasterópodos mariños con baixa capacidade dispersiva (ex. con desenvolvemento directo) presenten adaptacións a diferentes microhábitats dentro da mesma zona intermareal. Isto, é debido ás diferentes presións selectivas presentes nestes microhábitats (Galindo y Grahame, 2015). Nucella lapillus é unha das especies que presenta variabilidade fenotípica potencialmente adaptativa. Ademáis deste polimorfismo fenotípico, N. lapillus é unha das poucas especies, por non dicir a única, que presenta un polimorfismo cromosómico Robertsoniano (2n = 26-36) (Bantock e Cockayne, 1975) e, polo tanto, determinar se este constitúe unha barreira ó fluxo xénico e/ou se está relacionado con algún proceso adaptativo tamén representa un obxectivo importante posto que podería relacionar a evolución do xenoma con mecanismos ecolóxicos (ex. adaptación) e/ou a aparición de barreiras reprodutivas. A variación xenética detectada nas diferentes poboacións e as diferenzas observadas en función do seu grao de dispersión permitiranos determinar a futura dinámica de ditas poboacións nas costas galegas e, polo tanto, será importante para poder tomar as medidas pertinentes dende o punto de vista da conservación da biodiversidade e a estabilidade do ecosistema. One of the driving forces of evolution is the adaptive potential of species. The ability to adapt to new environmental conditions is of fundamental importance, among others, in processes of: a) ecological speciation leading to the formation of new species; b) adaptation to new conditions caused by drastic changes in ecosystems as a result of, for example, climate change and c) invasion of new ecosystems that can affect the stability thereof. Understanding these processes and the interactions among them is crucial in evaluating risks to the conservation of biodiversity. In the Galician coasts there are different species of gastropods belonging to the family Muricidae, all predating on bivalve’s molluscs. The native species, Nucella lapillus, presents a special interest, both at the morphological and chromosomal levels. Determining the genetic variability of this autochthonous species in the different populations will help us to improve our knowledge about the three processes mentioned above. The determination of the genetic variability of different populations of these species will help us to improve our understanding of the three processes mentioned previously. Species of marine gastropods with low dispersive capacity (eg. with direct development) commonly present adaptations to different microhabitats, in response to different selective pressures present in these microhabitats (Galindo and Grahame, 2015). Nucella lapillus is a specie that have potentially adaptive phenotypic variability. Moreover, N. lapillus is one of the few species showing a Robertsonian chromosomal polymorphism (2n = 26-36) (Bantock and Cockayne, 1975). Therefore, determining whether this polymorphism constitutes a barrier to gene flow and/or is related to some adaptive process is also important because it may relate genome evolution with ecological mechanisms (eg. adaptation) and/or the emergence of reproductive barriers. The genetic variation detected in these populations will be related to their degree of dispersion allowing us to predict future dynamics of these populations in Galicia and, therefore, taking appropriate measures for conservating biodiversity and stabilizing the ecosystem. Xunta de Galicia | Ref. GPC2013-011 Xunta de Galicia | Ref. ED431C 2016-037 Xunta de Galicia | Ref. ED481A-2015/441 Centro de Investigacións Mariñas Unión Europea

Size-assortative mating and sexual selection on size are common across species. Since both may be a result of mate choice, mate choice based on size should also be a widespread process. This behaviour is, however, rarely studied directly and thus the biological causes that determine size-based mate choice are poorly understood. To address this, we studied the size-based mate choice in an intertidal snail, Echinolittorina malaccana, that has been used as a model to understand this process. Previous studies, assuming a quantitative Gaussian mating preference function, have inferred that mate choice in this snail is caused by a size similarity mechanism (males prefer to mate with females slightly larger than themselves). To further test and quantify this proposed mechanism, we conducted mate choice experiments with alternative designs (single, male and multiple choice) in the laboratory and compared the results to mate choice data observed in natural populations. This integrated approach allowed us to elucidate the mechanism of mate choice by evaluating alternative mating models that best fitted the observed data of various designs. Results confirmed the similarity-based mechanism but showed deviations at extreme size classes. The single choice design indicated that mate choice was exercised during one-on-one maleefemale interactions, but the strength of mate choice increased with the presence of additional individuals (males in the male choice design, and both males and females in the multiplechoice design). Multiple-choice experiments are, therefore, the most valuable and useful design to infer how males choose mates in the wild, as they best mimic the natural scenario and the results are the most similar to those observed in natural populations. To elucidate the mechanisms causing this male choice for particular female sizes, the next steps are to identify the genetic basis as well as potential physiological benefits associated with choosing slightly larger females. Xunta de Galicia | Ref. ED431C 2020-05 Ministerio de Economía, Industria y Competitividad | Ref. CGL2016-75482-P

Meagre (Argyrosomus regius) is a teleost fish that has experienced an increase in Mediterranean aquaculture production in recent years. To improve productivity, it is necessary to establish a genetic selection program, but the generational interval in meagre is very high (2 and 3 years in males and females respectively). The objective of this survey is to evaluate the effect of specific A. regius single-chain recombinant gonadotropins (rGths) in prepubertal and sexually undifferentiated meagre. For this, 8 treatment groups were established, in which doses of 6, 12 or 18 μg / kg of rFSH or rLH were injected weekly for 3 weeks. Results did not show significant differences in GSI, but they did in plasma E2. Furthermore, early gonadal development was induced with the appearance of oocytes and spermatids in localized regions, while 100% of the fish in the saline group remained sexually undifferentiated. Our results on sexual differentiation show that with rGths therapy 1) males sexually differentiate earlier than females; 2) there is a higher proportion of males; 3) there are intersex fish. This is the first report of the presence of intersex fish and a male skewed ratio in this species. In conclusion, rGths therapy represent a potential solution to reduce the generation interval in prepubertal meagre, but more studies are needed to know how its administration affects during the period of sexual differentiation. Ciencias del Mar

Current methods for biomonitoring marine environments are aggressive, costly and time-consuming. DNA barcoding and metabarcoding offers a more accurate solution to this framework, but for this to be implemented, reliable reference sequences need to be available. The present study aimed to complete the reference database for metabarcoding studies. From an original list of 141 marine fish individuals, a total of 50 fish species were barcoded by PCR amplification of the 12s rRNA gene and sanger sequencing. A genetic analysis was additionally performed. Sequences are submitted to public access. Overall, DNA barcoding has shown to be a means by which marine resources could be surveyed without causing any negative impact. Ciencias del Mar

[ES] Se ha estudiado la divergencia genómica en 10 pequeñas poblaciones insulares de la lagartija balear (Podarcis lilfordi), en peligro de extinción, mediante la secuenciación del ADN asociada al sitio de restricción de doble digestión. Los objetivos eran establecer los niveles de divergencia entre las poblaciones, investigar el impacto del el tamaño de la población en la variabilidad genética y evaluar el papel de los diferentes factores ambientales en la adaptación local., [EN]Genomic divergence was studied in 10 small insular populations of the endangered Balearic Islands lizard (Podarcis lilfordi) using double digest restriction-site associated DNA sequencing. The objectives were to establish levels of divergence among populations, investigate the impact of population size on genetic variability and to evaluate the role of diferent environmental factors on local adaptation. Analyses of 72,846 SNPs supported a highly diferentiated genetic structure, being the populations with the lowest population size (Porros, Foradada and Esclatasang islets) the most divergent, indicative of greater genetic drift. Outlier tests identifed ~2% of loci as candidates for selection. Genomic divergence-Enviroment Association analyses were performed using redundancy analyses based on SNPs putatively under selection, detecting predation and human pressure as the environmental variables with the greatest explanatory power. Geographical distributions of populations and environmental factors appear to be fundamental drivers of divergence. These results support the combined role of genetic drift and divergent selection in shaping the genetic structure of these endemic island lizard populations.

Low dispersal marine intertidal species facing strong divergent selective pressures associated with steep environmental gradients have a great potential to inform us about local adaptation and reproductive isolation. Among these, gastropods of the genus Littorina offer a unique system to study parallel phenotypic divergence resulting from adaptation to different habitats related with wave exposure. In this study, we focused on two Littorina fabalis ecotypes from Northern European shores and compared patterns of habitat-related phenotypic and genetic divergence across three different geographic levels (local, regional and global). Geometric morphometric analyses revealed that individuals from habitats moderately exposed to waves usually present a larger shell size with a wider aperture than those from sheltered habitats. The phenotypic clustering of L. fabalis by habitat across most locations (mainly in terms of shell size) support an important role of ecology in morphological divergence. A genome scan based on amplified fragment length polymorphisms (AFLPs) revealed a heterogeneous pattern of differentiation across the genome between populations from the two different habitats, suggesting ecotype divergence in the presence of gene flow. The contrasting patterns of genetic structure between nonoutlier and outlier loci, and the decreased sharing of outlier loci with geographic distance among locations are compatible with parallel evolution of phenotypic divergence, with an important contribution of gene flow and/or ancestral variation. In the future, model-based inference studies based on sequence data across the entire genome will help unravelling these evolutionary hypotheses, improving our knowledge about adaptation and its influence on diversification within the marine realm Volkswagen Stiftung | Ref. 50500776 European Commission | Ref. 706376 European Marine Biological Resource Centre | Ref. 227799 Fundação para a Ciência e a Tecnologia | Ref. PTDC/BIA‐EVF/113805/2009 Fundação para a Ciência e a Tecnologia | Ref. PTDC/BIA‐EVL/30628/2017 Fundação para a Ciência e a Tecnologia | Ref. IF/00641/2014/CP1256/CT0008 Fundação para a Ciência e a Tecnologia | Ref. PD/BD/128350/2017 Ministerio de Ciencia, Innovación y Universidades | Ref. RTI2018- 101274-J-I00 Fundação para a Ciência e a | Ref. POCI-01-0145-FEDER-030628 European Regional Development Fund | Ref. FCOMP-01-0124-FEDER-014272

262 p. El objetivo general de esta Tesis Doctoral es el aprovechamiento y la utilización de las NGS (Next Generation Sequencing = tecnologías de secuenciación de segunda generación) para estudiar caracteres complejos y algunos fenotipos de importancia económica en el ganado ovino lechero. Todos los trabajos incluidos en esta Tesis Doctoral proporcionan una visión global de la gran utilidad del uso de las tecnologías de secuenciación para profundizar en distintos aspectos relacionados con la genómica animal.

214 p. La actual tesis doctoral, que se ha desarrollado en el grupo de investigación de mejora genética animal de la Universidad de León (grupo MEGA-ULE), tiene como objetivo global el estudio de la base genética subyacente a la resistencia a los nematodos gastrointestinales (GIN) en ovejas adultas. Para ello se han utilizado metodologías empleadas en la genómica, tales como el chip de genotipado de SNPs de alta densidad (HD) y las tecnologías se cuenciación conocidas como next generation sequencing (NGS). Para el cumplimiento el objetivo global se han abordado dos objetivos específicos. El primero de ellos tuvo por objeto realizar un mapeo de alta densidad de regiones con influencia sobre la resistencia a los GIN en ovejas mediante el análisis de genotipos imputados para el chip HD-chip en una población de raza Churra previamente analizada con el chip de media densidad (50K-chip) y para la cual estaban disponibles datos de dos fenotipos relacionados con la carga parasitaria. El segundo objetivo específico se centró en la caracterización funcional de regiones genómicas asociadas con la resistencia a los GIN en ovejas adultas, utilizando el análsis del transcriptioma completo de diferentes tejidos (ganglio linfático abomasal y mucosa del abomaso) después de la infección experimental con T. circumcincta, mediante la metodología RNAseq.

Natural color polymorphisms are widespread across animal species and usually have a simple genetic basis. This makes them an ideal system to study the evolutionary mechanisms responsible for maintaining biodiversity. In some populations of the intertidal snail Littorina fabalis, variation in shell color has remained stable for years, but the mechanisms responsible are unknown. Previous studies suggest that this stability could be caused by frequency-dependent sexual selection, but this hypothesis has not been tested. We analyzed shell color polymorphism in mating pairs and surrounding unmated individuals in two different populations of L. fabalis to estimate sexual fitness for color, as well as assortative mating. The estimated effective population size from neutral markers allowed us to disregard genetic drift as the main source of color frequency changes across generations. Shell color frequency was significantly correlated with sexual fitness showing a pattern of negative frequency dependent selection with high disassortative mating for color. The results suggested a contribution of male mate choice to maintain the polymorphism. Finally, the implementation of a multi-model inference approach based on information theory allowed us to test for the relative contribution of mate choice and mate competition to explain the maintenance of color polymorphism in this snail species Xunta de Galicia | Ref. ED431C 2016-037 Ministerio de Economía, Industria y Competitividad | Ref. CGL2016-75904-C2-1-P Ministerio de Ciencia, Innovación y Universidades | Ref. RTI2018-101274-J-I00 FCT – Foundation for Science and Technology | Ref. PTDC/BIA-EVL/30628/2017 FCT – Foundation for Science and Technology | Ref. POCI-01-0145-FEDER-030628 State Task RF | Ref. AAAAA19-119022690122-5

Segments of the genome enriched in repetitive sequences still present a challenge and are omitted in genome assemblies. For that reason, the exact composition of DNA sequences underlying the heterochromatic regions and the active centromeres are still unexplored for many organisms. The centromere is a crucial region of eukaryotic chromosomes responsible for the accurate segregation of genetic material. The typical landmark of centromere chromatin is the rapidly-evolving variant of the histone H3, CenH3, while DNA sequences packed in constitutive heterochromatin are associated with H3K9me3-modified histones. In the Pacific oyster Crassostrea gigas we identified its centromere histone variant, Cg-CenH3, that shows stage-specific distribution in gonadal cells. In order to investigate the DNA composition of genomic regions associated with the two specific chromatin types, we employed chromatin immunoprecipitation followed by high-throughput next-generation sequencing of the Cg-CenH3- and H3K9me3-associated sequences. CenH3-associated sequences were assigned to six groups of repetitive elements, while H3K9me3-associated-ones were assigned only to three. Those associated with CenH3 indicate the lack of uniformity in the chromosomal distribution of sequences building the centromeres, being also in the same time dispersed throughout the genome. The heterochromatin of C. gigas exhibited general paucity and limited chromosomal localization as predicted, with H3K9me3-associated sequences being predominantly constituted of DNA transposons. Hrvatska Zaklada za Znanost | Ref. IP-09-2014-3183 Xunta de Galicia | Ref. ED431C 2016-037 Xunta de Galicia | Ref. ED481B / 2018/091

Several features already qualified the invasive bivalve species Crassostrea gigas as a valuable non-standard model organism in genome research. C. gigas is characterized by the low contribution of satellite DNAs (satDNAs) vs. mobile elements and has an extremely low amount of heterochromatin, predominantly built of DNA transposons. In this work, we have identified 52 satDNAs composing the satellitome of C. gigas and constituting about 6.33% of the genome. Satellitome analysis reveals unusual, highly scattered organization of relatively short satDNA arrays across the whole genome. However, peculiar chromosomal distribution and densities are specific for each satDNA. The inspection of the organizational forms of the 11 most abundant satDNAs shows association with constitutive parts of Helitron mobile elements. Nine of the inspected satDNAs are dominantly found in mobile element-associated form, two mostly appear standalone, and only one is present exclusively as Helitron-associated sequence. The Helitron-related satDNAs appear in more chromosomes than other satDNAs, indicating that these mobile elements could be leading satDNA propagation in C. gigas. No significant accumulation of satDNAs on certain chromosomal positions was detected in C. gigas, thus establishing a novel pattern of satDNA organization on the genome level This work was supported by the following projects: Croatian Science Foundation, grant number IP-2019-045522; Xunta de Galicia (ED431C 2020/05) and the European Union (European Regional Development Fund—ERDF); Xunta de Galicia (Centro singular de investigación de Galicia, accreditation 2019-2022) and the European Union (European Regional Development Fund—ERDF). D.G.-S. is financially supported by Xunta de Galicia, a postdoctoral contract ED481B/2018/091 SI

17 pages, 8 figures, 4 tables.-- This article is licensed under a Creative Commons Attribution 4.0 International License, Common octopus, Octopus vulgaris, is an economically important cephalopod species. However, its rearing under captivity is currently challenged by massive mortalities previous to their juvenile stage due to nutritional and environmental factors. Dissecting the genetic basis and regulatory mechanism behind this mortality requires genomic background knowledge. A transcriptomic sequencing of 10 dph octopus paralarvae from different experimental conditions was constructed via RNA-seq. A total of 613,767,530 raw reads were filtered and de novo assembled into 363,527 contigs of which 82,513 were annotated in UniProt carrying also their GO and KEGG information. Differential gene expression analysis was carried out on paralarvae reared under different diet regimes and temperatures, also including wild paralarvae. Genes related to lipid metabolism exhibited higher transcriptional levels in individuals whose diet includes crustacean zoeas, which had an impact over their development and immune response capability. High temperature induces acclimation processes at the time that increase metabolic demands and oxidative stress. Wild individuals show an expression profile unexpectedly similar to Artemia fed individuals. Proteomic results support the hypothesis revealed by transcriptional analysis. The comparative study of the O. vulgaris transcriptomic profiles allowed the identification of genes that deserve to be further studied as candidates for biomarkers of development and health. The results obtained here on the transcriptional variations of genes caused by diet and temperature will provide new perspectives in understanding the molecular mechanisms behind nutritional and temperature requirements of common octopus that will open new opportunities to deepen in paralarvae rearing requirements, Proteomic and statistics analysis was performed in the SCSIE University of Valencia that belongs to ProteoRed PRB2-ISCIII, supported by grant PT13/0001 (PE I + D + i 2013–2016) funded by ISCIII and FEDERPT13/0001. This work was funded by “AGL20134910- C02–2R” and “AGL2017-89475-C2-1R” research projects from the Spanish Ministerio de Economía, Industria y Competitividad. P. García-Fernández thanks (PhD student “Marine Science, Technology and Management, University of Vigo”) Xunta de Galicia for his predoctoral fellowship (“Plan galego de investigación, innovación e crecemento 2011-2015 (Plan I2C)” ref. ED481A-2015/446). M. Prado-Alvarez thanks EU Marie-Sklodowska- Curie Actions for her postdoctoral contract MSC-IF-RESISGAL 659072. DGDLS is a Serra Húnter Fellow of the University of Barcelona

Terminal repeat retrotransposons in miniature (TRIMs) are small non-autonomous LTR retrotransposons consisting of two terminal direct repeats surrounding a short internal domain. The detection and characterization of these elements has been mainly limited to plants. Here we present the frst fnding of a TRIM element in bivalves, and among the frst known in the kingdom Animalia. Class Bivalvia has high ecological and commercial importance in marine ecosystems and aquaculture, and, in recent years, an increasing number of genomic studies has addressed to these organisms. We have identifed biv-TRIM in several bivalve species: Donax trunculus, Ruditapes decussatus, R. philippinarum, Venerupis corrugata, Polititapes rhomboides, Venus verrucosa, Dosinia exoleta, Glycymeris glycymeris, Cerastoderma edule, Magallana gigas, Mytilus galloprovincialis. biv-TRIM has several characteristics typical for this group of elements, exhibiting diferent variations. In addition to canonically structured elements, solo-TDRs and tandem repeats were detected. The presence of this element in the genome of each species is

La musaraña de campo, Crocidura suaveolens, tiene una distribución continua por gran parte de Eurasia y es una especie común y abundante. Sin embargo, en el oeste de Europa su distribución está fragmentada y es una especie rara y poco conocida en general. En la península ibérica, poco o nada se conoce sobre su historia, sobre su diversidad genética o sobre su ecología. Esta carencia de conocimiento impide una adecuada evaluación de la prioridad y el estado de su conservación. Las poblaciones del golfo de Cádiz, en particular, al estar situadas en el extremo suroeste de la distribución global de la especie y dado el pasado rol del sur ibérico como refugio glacial, podrían albergar una diversidad genética única que puede resultar clave para la persistencia de la especie ante el actual escenario de cambio global. La presente tesis doctoral tiene como finalidad inferir la historia evolutiva y demográfica de la musaraña de campo en la península ibérica y evaluar su distribución, estado génico y ecología en el golfo de Cádiz, con el objetivo final de contribuir a la evaluación del estado de conservación y, en su caso, al diseño de un plan de gestión de la especie en esta región. Para este propósito, se usaron egagrópilas de lechuza común, Tyto alba, y trampas Trip Trap de captura en vivo como principales métodos de muestreo de la especie, así como diferentes técnicas de genética molecular para la caracterización genética de las muestras obtenidas. Todas las poblaciones de musaraña de campo de la península ibérica pertenecen al clado IV del grupo C. suaveolens. Dentro de este clado, se han identificado tres linajes evolutivos mitocondriales, dos de ellos exclusivamente ibéricos. Las poblaciones del golfo de Cádiz presentan dos sublinajes exclusivos de uno de estos linajes ibéricos. La historia evolutiva de la musaraña de campo en la península ibérica puede ser explicada por la existencia de múltiples refugios glaciares para la especie en la península ibérica y la competencia con la musaraña gris, Crocidura russula, tras su llegada desde África hace aproximadamente 126.000 años. En el golfo de Cádiz la musaraña de campo está solo presente en seis marismas mareales distribuidas en cuatro áreas marismeñas aisladas entre sí: las marismas de los ríos Guadiana (orilla española), Piedras, Odiel, Tinto, Estero Domingo Rubio y Guadalquivir. La especie presenta una fuerte estructura genética como resultado de un alto nivel de aislamiento poblacional, con seis grupos genéticos diferenciados correspondientes a cada una de las seis marismas ocupadas por la especie. Guadalquivir y Estero Domingo Rubio son las poblaciones más diferenciadas genéticamente, mientras que las poblaciones del Guadiana, Piedras, Odiel y Tinto son genéticamente más parecidas entre sí. El flujo génico entre poblaciones está limitado porque la especie no dispersa a través de hábitats no marismeños. Los cauces fluviales más anchos también limitan el flujo génico, pero no parecen constituir barreras absolutas para la dispersión. Se han observado niveles moderados de diversidad local y altos niveles de diversidad genética regional, lo que convierte al golfo de Cádiz en una región con un gran potencial evolutivo para afrontar futuras amenazas. La musaraña de campo es especialista de hábitat de marisma mareal en el golfo de Cádiz, siendo el único caso conocido de especialización en la especie. Su especialización de hábitat parece ser un efecto evolutivo de la competencia pasada con la musaraña gris, que ha favorecido la coexistencia de las dos especies en la región mediante la segregación espacial y temporal de sus nichos ecológicos. La musaraña de campo excluye competitivamente a la musaraña gris de las marismas mareales, invirtiendo el patrón de dominancia habitual en simpatría. La historia evolutiva de las poblaciones de musaraña de campo del golfo de Cádiz, su distribución, su composición genética y su ecología pueden ser explicadas por la acción combinada de la competencia con la musaraña gris, la especialización de la musaraña de campo en marisma mareal y la evolución geomorfológica de las marismas mareales de esta región., The lesser white-toothed shrew, Crocidura suaveolens, is continuously distributed, common and abundant throughout most Eurasia. However, in Western Europe its distribution is fragmented and it is a rare and poorly known species. In the Iberian Peninsula, the lack of knowledge about its history, its genetic diversity or its ecology hampers a proper assessment of its conservation priority and status. The populations of the Gulf of Cádiz, in particular, being located in the southwestern limit of the global distribution of the species and given the prominent role of the Iberian Peninsula as glacial refugia, could harbour a unique genetic diversity which may be key for the species persistence in the current scenario of global change. This doctoral thesis aims to describe the evolutionary and demographic history of C. suaveolens in the Iberian Peninsula and to assess its distribution, genetic status and ecology in the Gulf of Cádiz, with the final intention of contributing to the assessment of its conservation status and, where appropriate, to the design of a management plan for the species in this region. For this purpose, I used barn owl, Tyto alba, pellets and Trip Trap live traps to sample individuals, and applied different molecular genetic techniques for the genetic characterization of these samples. All the C. suaveolens populations in the Iberian Peninsula cluster within the previously described clade IV of the C. suaveolens group. Within this clade, three evolutionary mitochondrial lineages have been identified, two of which are exclusively Iberian. Two sublineages within one of these Iberian lineages are exclusive of the populations in the gulf of Cádiz. The evolutionary history of C. suaveolens in the Iberian Peninsula can be explained by the existence of multiple refugia within the Iberian Peninsula and the competition with the greater white-toothed shrew, Crocidura russula, that started with its arrival from Africa ca. 126 Kya. In the Gulf of Cádiz C. suaveolens is present only in six tidal marshes located in four isolated marsh areas: the marshes of the rivers Guadiana (Spanish shore), Piedras, Odiel, Tinto, Estero Domingo Rubio and Guadalquivir. The species has a marked genetic structure as a result of a high level of population isolation, with six differentiated genetic groups corresponding to the six marshes occupied by the species. Guadalquivir and Estero Domingo Rubio are the most genetically differentiated populations, while the populations of Guadiana, Piedras, Odiel and Tinto are genetically more similar to each other. Gene flow between populations is restricted because the species does not disperse through non-marsh habitats. Wider river channels also limit gene flow, but they do not appear to be absolute barriers to dispersal. Moderate levels of local and high levels of regional genetic diversity have been observed, making the Gulf of Cádiz a region with a great evolutionary potential to face future threats. C. suaveolens is a tidal marsh habitat specialist in the Gulf of Cádiz, being the only known case of habitat specialization described for the species. Its habitat specialization in the region seems to be an evolutionary effect of past competition with C. russula, which is allowing the coexistence of the two species through the spatial and temporal segregation of their ecological niches. C. suaveolens is currently outcompeting C. russula in tidal marshes, reversing the dominance pattern observed elsewhere. The evolutionary history of the C. suaveolens populations of the Gulf of Cádiz, its distribution, genetic composition and ecology, can be explained by the competition with C. russula, the specialization of C. suaveolens in tidal marsh and the geomorphological evolution of tidal marshes of this region.

P. 14-32 La raza de lidia se origina en la Edad Media en España y está constituida por 5 castas, 16 encastes y 6 líneas genéticas. En los últimos años el número de efectivos se ha visto disminuido por la crisis económica, que ha hecho a muchos ganaderos reducir o sustituir sus animales por razas más rentables. A pesar de que la raza no es considerada en peligro de extinción por el MAGRAMA, un censo realizado en 2010 arrojó datos alarmantes: 16 encastes en situación de peligro de extinción (con menos de 1000 vacas madres cada uno). La demostrada importancia genética del ganado de lidia hace necesaria una mayor coordinación entre los organismos y entidades implicados en su explotación y a su vez conveniente el establecimiento de un centro de estudio y conservación de la raza, que disponga del banco de germoplasma con un volumen suficiente de material genético que asegure su supervivencia. SI

9 páginas, 3 figuras, 2 tablas.-- This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY), The common octopus, Octopus vulgaris, is a good candidate for aquaculture but a sustainable production is still unviable due to an almost total mortality during the paralarvae stage. DNA methylation regulates gene expression in the eukaryotic genome, and has been shown to exhibit plasticity throughout O. vulgaris life cycle, changing profiles from paralarvae to adult stages. This pattern of methylation could be sensitive to small alterations in nutritional and environmental conditions during the species early development, thus impacting on its health, growth and survival. In this sense, a full understanding of the epigenetic mechanisms operating during O. vulgaris development would contribute to optimizing the culture conditions for this species. Paralarvae of O. vulgaris were cultured over 28 days post-hatching (dph) using two different Artemia sp. based diets: control and a long chain polyunsaturated fatty acids (LC-PUFA) enriched diet. The effect of the diets on the paralarvae DNA global methylation was analyzed by Methyl-Sensitive Amplification Polymorphism (MSAP) and global 5-methylcytosine enzyme-linked immunosorbent assay (ELISA) approaches. The analysis of different methylation states over the time revealed a global demethylation phenomena occurring along O. vulgaris early development being directly driven by the age of the paralarvae. A gradual decline in methylated loci (hemimethylated, internal cytosine methylated, and hypermethylated) parallel to a progressive gain in non-methylated (NMT) loci toward the later sampling points was verified regardless of the diet provided and demonstrate a pre-established and well-defined demethylation program during its early development, involving a 20% of the MSAP loci. In addition, a differential behavior between diets was also observed at 20 dph, with a LC-PUFA supplementation effect over the methylation profiles. The present results show significant differences on the paralarvae methylation profiles during its development and a diet effect on these changes. It is characterized by a process of demethylation of the genome at the paralarvae stage and the influence of diet to favor this methylation loss, This work was funded by “AGL20134910-C02-2R” research Project from the Spanish Ministerio de Economía, Industria y Competitividad. PG (PhD student “Marine Science, Technology and Management–University of Vigo”) thanks Xunta de Galicia for his predoctoral fellowship (“Plan galego de investigación, innovación e crecemento 2011-2015 (Plan I2C)” ref. ED481A-2015/446), We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).

El libro del primer congreso internacional “Epilepsia Audiógena: de los modelos a la clínica” contiene las presentaciones y contribuciones realizadas por los investigadores en la conferencia. El congreso se celebró en Salamanca del 9 al 12 de Septiembre de 2014. La sede del congreso es el Instituto de Neurociencias de Castilla y León (INCyL), un centro dedicado a la investigación científica en el sistema nervioso y sus patologías así como a la formación de nuevos investigadores y a la divulgación científica. El congreso tuvo un programa científico de excelencia, diverso y compacto centrado en los modelos experimentales de epilepsias reflejas y su relación con la clínica. Los participantes tuvieron la oportunidad de disfrutar de conferenciantes invitados de reconocido prestigio mundial en el campo de la epilepsia. De especial interés fueron los principales temas tratados durante el congreso: epilepsia refleja, modelos de epilepsia audiógena, modelos genéticos de epilepsia, fármacos antiepilépticos y epilepsias humanas., The programme book of the the First International Conference “Audiogenic Epilepsy: from Animal Models to the Clinic” contains the proceedings and contributions made by researchers at the conference. The Congress was held at the Neuroscience Institute of Castilla y León (INCyL), Salamanca, Spain, from September 9th – 12th, 2014 and focused on a broad spectrum of cutting-edge epilepsy research and technologies. During the conference, we had the opportunity to enjoy with excellent and internationally well-recognized keynote speakers. This Congress was intended to be a consolidated forum for multidisciplinary interaction between basic research and clinical scientists, working at the genetic-molecular, cellular, and behaviour levels. Of special interest were the main topics of the Congress: reflex epilepsies, audiogenic seizure models, genetic models of epilepsy, antiepileptic drugs, and human epilepsies, Fundación Ramón Areces, Fundación Alicia Koplowitz, Esteve Veterinaria, Instituto de Biomedicina de Salamanca (IBSAL), Univeridad de Salamanca, Instituto de Neurociencias de Castilla y León (INCYL), Charles River, Fotocopias Idem, Microsercon, Ayuntamiento de Salamanca

La cherna Polyprion americanus es un componente de las pesquerías multiespecíficas en todo su rango de distribución y recientemente ha sido identificada por su gran potencial de acuicultura. Por ello, en la última década se fundaron varios stocks en piscifactorías gallegas. La combinación de marcadores genéticos con estrategias clásicas de domesticación parece ser un método útil para evitar la deriva genética y los efectos adversos derivados de la consanguínidad. En este estudio hemos aplicado marcadores microsatélites a los cuatro stocks de cherna disponibles en criaderos gallegos, para determinar el grado de divergencia genética, así como a una población salvaje del Atlántico. Demostramos que existe diferenciación genética significativa (5,43% de la varianza genética) debida a la deriva de muestreo y una pronunciada pérdida de diversidad (44% de la diversidad alélica) en el 80% de los stocks con respecto a la riqueza genética de la población salvaje. Con marcadores moleculares también hemos testado el resultado de dos estrategias de apareamiento dentro y entre poblaciones, con el objetivo de determinar la más adecuada para la gestión de este recurso en el espacio y tiempo, usando simulaciones in silico. Los resultados muestran que un escenario de cruzamientos inter-criadero resulta mucho más ventajoso para evitar la endogamia que el apareamiento dentro de cada criadero. La cherna es un pez pelágico de larga vida con una fase adulta demersal que muestra una distribución antitropical a lo largo del Océano Atlántico, el Océano Indico y el Océano Pacífico. Estudios genéticos anteriores han sugerido una diferenciación importante entre el Atlántico Norte y Atlántico Sur usando ADN mitocondrial y marcadores microsatélites. Sin embargo, no ha podido demostrarse hasta el momento si existe o no una mayor estructuración dentro del Atlántico Norte, aparentemente homogéneo. Hemos aplicado marcadores microsatélites neutros y secuencias, nucleares y mitocondriales a un muestreo temporal de chernas del Atlántico Norte para clarificar esta situación. Los datos experimentales muestran un valor de diferenciación global entre muestras de 12.7% debido a la divergencia entre los tres diferentes pools génicos: Atlántico Norte, Atlántico Sur y Oceanía. Sin embargo, las poblaciones atlánticas parecen conectarse sistemáticamente a través de migraciones longitudinales desde Caroline USA hacia aguas del este Atlántico. Este resultado es clave para entender la dinámica de poblaciones que rige a las chernas, así como para el diseño correcto de sus estrategias de explotación. Como indicamos, la cherna tiene alto valor comercial, alta tasa de crecimiento en la fase juvenil, carne de buena calidad y gran potencial en la acuicultura, pero todavía hay muy poca información sobre su tecnología de cultivo. El objetivo de este estudio es describir el comportamiento reproductivo de la cherna en los tres criaderos de la costa de Galicia: el Centro Oceanográfico de Vigo (IEO-Vigo), el Instituto Gallego de Formación en Acuicultura (IGAFA) y el Aquarium Finisterrae, entre 2011 y 2013. Durante ese período se efectuó el seguimiento de parámetros tales como crecimiento, nutrición y reproducción. Se tomaron muestras sanguíneas en el IEO-Vigo para el análisis de la madurez sexual mediante la técnica de Palma (1986), donde se midieron los niveles de varias hormonas, i.e. 17-beta-estradiol (E2), testosterona (T) y la testosterona 11-ceto (11-KT). Aunque la madurez sexual se ha confirmado en algunos individuos, solamente se observó un desove en un tanque de prueba, con y sin inducción sexual. En cuanto a género, peso y crecimiento, estos evolucionaron significativamente (p < 0.05) en los stocks del IGAFA y el IEO. Se observaron diferencias significativas en la ganancia de peso entre los sexos en los tanques del Aquarium Finisterrae y el IEO.

Esta tesis doctoral trata varias cuestiones pendientes en la estructura poblacional de las poblaciones del mejillón Mytilus galloprovincialis que habitan las costas de Marruecos y que son necesarias para llevar a cabo un plan de gestión genética de este recurso genético. A lo largo de cuatro capítulos, los pooles genéticos de mejillón presentes en Marruecos se ponen en relación con otros pooles presentes en el mundo, bien basándose en estudios previos llevados a cabo con marcadores moleculares, bien en la variación observada con microsátelites descrita aquí a todas las escalas geográficas. El capítulo I trata la variación observada con microsatélites en las poblaciones de mejillón que habitan el Mar de Alborán, una zona de transición biogeográfica para muchas especies, entre el Atlántico y el Mediterráneo. Los marcadores microsatélites muestran un flujo génico limitado entre las poblaciones de mejillón de las costas Atlánticas ibéricas y los de las costas marroquís (FST±SD = 0.041±0.002). Esta divergencia latitudinal en la zona biogeográfica Gibraltar-Alborán nos indica heterogeneidad genética que es probablemente debida a la interacción entre la capacidad dispersiva larvaria y el complejo patrón de condiciones físicas y corrientes oceanográficas de esa zona. El capítulo II extiende la reducida escala geográfica estudiada en el capítulo previo a toda la costa de Marruecos, para establecer el número de pooles génicos locales. Se observan dos pooles génicos divergentes en Marruecos (FST±SD = 0.038±0.010): un grupo de poblaciones confinado en el Mar de Alborán y otro que se extiende a lo largo de la fachada Atlántica marroquí. El conocido como Frente Oceanográfico Almería Orán (AOOF) se aplica para establecer la divergencia relativa entre los pooles génicos (FST±SD = 0.074±0.010) que se encuentran en esa latitud: el Mediterráneo, el Atlántico Marroquí y el Atlántico Ibérico. La importancia de la existencia de varios pooles génicos en contacto, se discute en términos de dinámica biogeográfica, así como también su implicación en la gestión genética de las poblaciones de mejillón cultivadas en el norte de Marruecos. El capítulo III está motivado por la dificultad para identificar el número de pooles génicos de Mytilus galloprovincialis en el mundo, debido a su cercanía genética a otras especies del género. Este hecho impulsó a aislar nuevos marcadores microsatélites del chorito o mejillón chileno (Mytilus chilensis) y a testar su amplificación en el resto de especies congenéricas. La ausencia de amplificación interespecífica y/o de polimorfismo de la mayoría de los microsatélites de M. chilensis en el género, permite proponer un estatus taxonómico propio para esta especie. En el capítulo IV se aborda el muestreo a escala mundial para determinar el número de stocks de M. galloprovincialis. Se identificaron cinco unidades génicas bien justificadas, que mostraron un gran divergencia entre ellas (FST±SD = 0.096±0.012), posiblemente resultado de la hibridación (M. galloprovincialis x M. trossulus en las costas de California) y de la deriva (e.g. el stock japonés). El porcentaje de variación respecto a otras especies congenéricas fue elevado (M. galloprovincialis vs. M. trossulus, M. edulis y M. chilensis, i.e. 24.16 %, 10.22 % y 6.17 %, respectivamente). Por otra parte se confirma también con microsatélites la presencia de M. galloprovincialis en la costa central Chile. La genética de poblaciones de mejillón abordada en esta tesis, puede resultar muy útil para la incipiente gestión acuícola de sus poblaciones en Marruecos (detección de deriva, heterosis, etc.) así como para la gestión y conservación de pesquerías (mantenimiento de diversidad genética zonal) o para la trazabilidad comercial de los stocks de mejillón. The current thesis addresses several pending questions on the population structure of the mussel Mytilus galloprovincialis inha biting the Moroccan shores that are required to work out a proper population manage ment of this Moroccan genetic resource . Throughout the four chapters, the Moroccan mussel gene pools are put in relation to other world - round mussel gene pools both, based o n previous knowledge afforded with molecular markers as well as on present microsatellite variation described at large geographical scales. Chapter I addresses microsatellite variation of mussel populations inhabiting the Alboran Sea, a biogeographic trans ition zone between the Atlantic and the Mediterranean for many species. M icrosatellites markers unveiled a limited gene flow between mussels from Atlantic Iberia coasts and those from Morocco coasts ( F ST ± SD = 0.041±0.002). This latitudinal divergence withi n the same oceanographic area tells about a population genetic heterogeneity around the Gibraltar - Alboran biogeographic zone that is likely shaped by larvae dispersal ability under a complex physical and oceanographic current pattern in the area. Chapter I I enlarges the reduced geographical scale addressed in the previous chapter to the whole Moroccan coast, aiming to establish the true number of gene pools inhabiting this area. T wo major divergent genetic pools ( F ST ± SD = 0 . 038±0 . 010) were observed in Moroc co, one group of populations confined to the Alboran Sea and other one extend ing along the Atlantic Moroccan façade. The well - known Almeria Oran Oceanographic Front (AOOF) served at establishing the relative divergence among gene pools ( F ST ± SD = 0 . 074±0 . 01 0) colliding in this area: the Mediterranean pool, the Atlantic Moroccan pool and the Atlantic Iberian pool. The importance of concomitant genetic pools in this area is discussed in terms of basic biogeographic dynamics as well as on its implication on the genetic management of mussel aquaculture pools in northern Morocco. Chapter III is motivated by t he difficulty at identifying the number of world gene pools of Mytilus galloprovincialis due to its closeness to other sister species. This fact led us to iso late new polymorphic microsatellites from the Chilean blue mussel ( Mytilus chilensis ) and to cross - species testing of its amplification. Failure of most M. chilensis microsatellite primers to amplify in other species of genus Mytilus or being monomorphic, allowed to consider a proper genetic status to the southern Chilean blue mussel M. chilensis within this genus. Chapter IV addresses a world - wide macro - scale sampling study was developed to depict the number of divergent stocks of M . galloprovincialis . Fiv e well supported world regional genepools were found showing a large genetic divergence among them ( F ST ±SD = 0.096±0.012) as a result of hybridisation ( M. galloprovincialis x M. trossulus at Californian coasts) and drift (e.g., the Japanese stock). Percen tage of variation was large between the four species considered ( M. galloprovincialis vs . M. trossulus, M. edulis and M. chilensis , i.e. 24.16%, 10.22% and 6.17% , respectively), and the presence of M. galloprovincialis in Central Chile was patently establi shed after this study. The population genetic information offered in this thesis is useful to the incipient aquaculture management of Mytilus stocks in Morocco (drift detection, across - stocks heterosis, etc.) as well as for fishery restoration and conserva tion (zonal enhancement of gene diversity), of for the molecular traceability of commercial mussel stocks.

[spa] La sobreexplotación pesquera es un gran problema actual, por lo que científicos y gestores tratan de evaluar los riesgos de colapso y proponer planes estratégicos para mejorar la sostenibilidad de las pesquerías. El análisis genético espacio-temporal de los recursos pesqueros describe el patrón conectivo existente entre poblaciones y su estabilidad temporal, por lo que la inclusión de datos genéticos en los planes estratégicos está cada vez más demandada. Los datos moleculares obtenidos con marcadores microsatélite y secuencias de ADN mitocondrial de merluza europea (Merluccius merluccius), muestreada en todo su rango de distribución durante la última década, han permitido establecer importantes propiedades genético-poblacionales de esta pesquería. El patrón de conectividad a gran escala, obtenido tras la aplicación de un reloj molecular mitocondrial, sitúa en el Pleistoceno tardío (ca. 150.000 años) el comienzo de la divergencia genética entre las poblaciones de las dos principales vertientes europeas. La merluza atlántica parece constituir una población panmíctica, que se extiende desde el norte de Irlanda hasta el Mar Canario, mostrando únicamente una reducción al flujo génico respecto a la población más extrema del Mar del Norte. La migración latitudinal hacia el sur, planteada en esta tesis, sugiere un desplazamiento significativo de biomasa desde las principales áreas de freza de esta especie, del oeste y sur de Irlanda (Porcupine Bank y Great Sole) hacia latitudes septentrionales del llamado Stock Sur (Mar Cantábrico). El escenario panmíctico descrito para la merluza europea se alterna con episodios de divergencia metapoblacional y por tanto su gestión genética debería evitar visiones estructuralistas infundadas. De hecho, el seguimiento interanual de la diversidad genética de esta especie, medida a través de su tamaño efectivo poblacional, parece ser un buen estimador de su status genético. Además, este indicador genético se correlaciona estrechamente con estimas de biomasa aportadas por otras disciplinas científicas. Los resultados presentados en esta tesis son relevantes para la gestión genética de largo plazo en esta especie, enfocada a su sostenibilidad ecológica y comercial. [eng] The overexploitation of fisheries is a major problem nowadays and therefore scientists and managers try to assess the risks of collapse and to propose strategic plans to improve the sustainability of fisheries. Spatio-temporal genetic analyses of marine resources help to describe the connectivity pattern existing across populations and its temporal stability, so the inclusion of this type of data into strategic plans is increasingly demanded. Present molecular data obtained from microsatellite markers and mitochondrial DNA sequences on European hake (Merluccius merluccius) samples collected from its whole distribution range during the last decade, have allowed to establishing important eco-biological properties of this fishery. The macroscale pattern of connectivity recovered upon a mitochondrial clock situates the initial divergence between populations of the two main European basins in the Late Pleistocene (ca. 150,000 yr bp). The Atlantic hake conforms a single panmictic population extending from Northern Ireland to the Canarian Sea and only the North Sea population exhibits a limited gene flow with the rest of Atlantic grounds. A southwards latitudinal migration pattern put forward in this thesis, suggests that a significant biomass displacement occurs systematically from the main spawning grounds of the species in Southwestern Ireland (Great Sole and Porcupine Bank grounds) to northern latitudes of the Southern Stock (Cantabrian Sea). The panmictic scenario proposed for the European hake alternates episodes of metapopulation divergence and therefore its genetic management should ignore unfounded structural criteria. In fact, the interannual monitoring of the genetic diversity of this species, measured through its effective genetic population size, appears to be a good predictor of its genetic status and correlates tightly with biomass trends from interdisciplinary records. The results presented in this thesis are of upmost relevance for the long-term genetic management of this European species regarding its ecological and commercial sustainability.

206 p. [ES] En la presente tesis se ha procedido a analizar el efecto del tiempo de conservación postmortem, del medio de dilución y del método de selección espermática sobre las características de calidad del semen epididimario del toro de Lidia. Para ello se recogieron los testículos, inmediatamente después del sacrificio de los animales. El estudio de los parámetros seminales se realizó en diferentes momentos del proceso: antes de la dilución de las muestras, durante la refrigeración, una vez descongelados y después de la descongelación y de la selección espermática, estudiando además la capacidad de fecundación y la división embrionaria de dichas muestras. En todos los casos, la calidad de los espermatozoides epididimales de toro de Lidia almacenados en la cola epididimaria, decayó con el tiempo de conservación postmortem, manteniendo la calidad, aunque con un ligero descenso, hasta las 24 horas de almacenamiento. Los métodos de selección evaluados, “swim-up” y gradiente de densidad, consiguieron fecundar y dividir los ovocitos, aunque se obtuvo una mejor calidad espermática en las muestras seleccionadas mediante ¿swim-up¿, los espermatozoides presentaron un mayor número de alteraciones y/o reacción acrosomal. La separación por gradiente de densidad, proporcionó muestras con una mayor concentración espermática, que también presentaban una buena calidad. Los espermatozoides, congelados-descongelados, recogidos de epidídimos almacenados a 5 ºC, durante 24 horas, mostraron una capacidad fecundante similar que la de los no conservados. Si bien los espermatozoides almacenados durante un periodo más largo, lograron fecundar y dividir al ovocito, éstos lo hicieron en un porcentaje inferior a los anteriores

Publicado en el año 2008 en: Revista ITEA, 104 (2), 283-289. http://www.aida-itea.org/index.php/revista/contenidos?idArt=85&lang=esp Webs desde donde descargar las ponencias: http://acteon.webs.upv.es/ Web del congreso: http://www.uco.es/genetica/MERAGEM/xivreunion.htm Se han estudiado la variabilidad y relaciones genéticas de las cuatro poblaciones equinas de aptitud cárnica de España de protección especial (41 muestras) (Burguete (BUR): 10, Jaca Navarra (JAC): 11, Hispano Bretón (HB): 10 y Agrupación Hipermétrica del Pirineo (AHP): 10) a través del estudio del ADN mitocondrial (ADNmt). Se han encontrado 15 haplotipos en las 4 razas analizadas determinados por la existencia de 19 posiciones polimórficas de las cuales 18 han sido posiciones informativas parsimoniosas y 1 no informativa (singleton). La diversidad haplotípica (Hd) ha oscilado entre 0,758 del AHP y 0,993 del BUR siendo el valor medio de todas las razas de de 0,929 (SD = 0,016). La raza JAC ha presentado el mayor valor de diversidad nucleotídica (0,023). Casi la totalidad de los haplotipos encontrados los han compartido las razas analizadas excepto el haplotipo 8 que sólo lo ha presentado la AHP, el haplotipo 10 la raza BUR, los haplotipos 13 y 14 el HB y el haplotipo 15 la raza JAC. No se ha encontrado un agrupamiento claro de las poblaciones analizadas, lo que confirma los múltiples orígenes maternos previamente indicado por varios autores. No obstante, al haberse encontrado haplotipos específicos en las 4 poblaciones analizadas se deben tenerlos en cuenta a la hora de llevar a cabo los planes de conservación. Genetic variability and phylogenetic relationships of the autochthonous horse breed for meat production based on mitochondrial DNA We have studied the genetic variability and relationships of four endangered Spanish equine populations for meat production using mitochondrial DNA (mtDNA) (41 horses, 30 of them belong to Burguete (BUR), Hispano Bretón (HB) and Agrupación Hipermétrica del Pirineo (AHP) populations and the other 11 samples belong to Jaca Navarra (JAC) breed. Fifteen haplotypes were found and 19 polomorphic sites were detected, eighteen of them were parsimony informative sites and the other one was a singleton. Haplotipic diversity (Hd) ranged from 0.758 of AHP to 0.993 of BUR breed. The average Hd value was 0.929 (SD = 0.016). The JAC breed presented the highest nucleotide diversity value (0.023). Most of haplotypes found have been shared by the four horse populations except haplotype 8 that only was presented by AHP populaton, haplotype 10 by BUR, the haplotypes 13 and 14 by HB and haplotype 15 by JAC breed. A clear group of horses belong to the same population were not shown. These results confirm the multiple maternal origin previously shown by other authors. However we have found haplotypes specific of each breed that is important to take in account in their conservation programmes.

El ganado porcino tiene una gran importancia económica, y depende en gran medida de la utilización de la inseminación artificial. El objetivo de este trabajo es llevar a cabo una revisión bibliográfica sobre métodos novedosos basados en biomarcadores que permitan optimizar la detección temprana de daños en el ADN espermático de cerdo. Diversos estudios han establecido una alta correlación entre la calidad del ADN espermático y la fertilidad de las muestras utilizadas en la reproducción asistida en especies porcinas. Los métodos clásicos de evaluación de muestras de semen (SCSA, COMET, TUNEL, etc.) en muchas ocasiones no proporcionan datos fiables sobre la calidad del ADN. Esto ha impulsado la búsqueda de novedosas técnicas inmunoquímicas basadas en biomarcadores oxidativos como los aductos de 8-OHdG y modificaciones epigenéticas (acetilaciones y metilaciones) en histonas que permitan una temprana detección de ADN espermático de baja calidad, ya que se considera la causa principal de la infertilidad y los tamaños reducidos de las camadas. Los avances en este campo supondrán grandes beneficios económicos para el sector porcino. Palabras clave: alteraciones epigenéticas, cromatina, daño espermático, daño oxidativo, espermatozoide porcino, histonas.