III. Unidades de Investigação, Desenvolvimento e Outras
Permanent URI for this community
Browse
Browsing III. Unidades de Investigação, Desenvolvimento e Outras by Author "A, Serrão"
Now showing 1 - 10 of 12
Results Per Page
Sort Options
- A transcriptome resource for the copepod Calanus glacialis across a range of culture temperaturesPublication . A Ramos, Ana; Weydmann, A.; Cox, C. J.; Canario, A.V.M.; A, Serrão; Pearson, G. A.The copepod Calanus glacialis plays a key role in the Arctic pelagic ecosystem. Despite its ecological importance and ongoing climate changes, limited knowledge at the genomic level has hindered the understanding of the molecular processes underlying environmental stress responses and ecological adaptation. Transcriptome data was generated from an experiment with C glacialis copepodite (CV) subjected to five different temperatures. We obtained a total of 512,352 high-quality 454 pyrosequencing reads, which were assembled into 55,562 contigs distributed in 128 KEGG pathways. Functional analysis revealed numerous genes related to diverse biological functions and processes, including members of all major conserved signaling pathways. Comparative analysis of acclimated individuals to experimental temperatures has provided information about gene variations observed in several pathways (e.g. genes involved in energy, lipid and amino acid metabolism were shown to be down-regulated with increasing temperatures). These mRNA sequence resources will facilitate further studies on genomics and physiology-driven molecular processes in C glacialis and related species. (C) 2015 Elsevier B.V. All rights reserved.
- Complete mitochondrial genome of the branching octocoral Paramuricea grayi (Johnson, 1861), phylogenetic relationships and divergence analysisPublication . Coelho, Márcio; Ledoux, Jean-Baptiste; Boavida, Joana; Paulo, Diogo; Gómez-Gras, Daniel; Bensoussan, Nathaniel; López-Sendino, Paula; Cerrano, Carlo; Kipson, Silvija; Bakran-Petricioli, Tatjana; Garrabou, Joaquim; A, Serrão; Pearson, GarethThe Gray's sea fan, Paramuricea grayi (Johnson, 1861), typically inhabits deep littoral and circalittoral habitats of the eastern temperate and tropical Atlantic Ocean. Along the Iberian Peninsula, where P. grayi is a dominant constituent of circalittoral coral gardens, two segregating lineages (yellow and purple morphotypes) were recently identified using single-copy nuclear orthologues. The mitochondrial genomes of 9 P. grayi individuals covering both color morphotypes were assembled from RNA-seq data, using samples collected at three sites in southern (Sagres and Tavira) and western (Cape Espichel) Portugal. The complete circular mitogenome is 18,668 bp in length, has an A + T-rich base composition (62.5%) and contains the 17 genes typically found in Octocorallia: 14 protein-coding genes (atp6, atp8, cob, cox1-3, mt-mutS, nad1-6, and nad4L), the small and large subunit rRNAs (rns and rnl), and one transfer RNA (trnM). The mitogenomes were nearly identical for all specimens, though we identified a noteworthy polymorphism (two SNPs 9 bp apart) in the mt-mutS of one purple individual that is shared with the sister species P. clavata. The mitogenomes of the two species have a pairwise sequence identity of 99.0%, with nad6 and mt-mutS having the highest rates of non-synonymous substitutions.
- Entangled fates of holobiont genomes during invasion: nested bacterial and host diversities in Caulerpa taxifoliaPublication . ARNAUD-HAOND, Sophie; Aires, T; Candeias, R.; Teixeira, S. J. L.; Duarte, C. M.; Valero, M.; A, SerrãoSuccessful prevention and mitigation of biological invasions requires retracing the initial steps of introduction, as well as understanding key elements enhancing the adaptability of invasive species. We studied the genetic diversity of the green alga Caulerpa taxifolia and its associated bacterial communities in several areas around the world. The striking congruence of alpha and beta diversity of the algal genome and endophytic communities reveals a tight association, supporting the holobiont concept as best describing the unit of spreading and invasion. Both genomic compartments support the hypotheses of a unique accidental introduction in the Mediterranean and of multiple invasion events in southern Australia. In addition to helping with tracing the origin of invasion, bacterial communities exhibit metabolic functions that can potentially enhance adaptability and competitiveness of the consortium they form with their host. We thus hypothesize that low genetic diversities of both host and symbiont communities may contribute to the recent regression in the Mediterranean, in contrast with the persistence of highly diverse assemblages in southern Australia. This study supports the importance of scaling up from the host to the holobiont for a comprehensive understanding of invasions.
- Exploring the response of a key Mediterranean gorgonian to heat stress across biological and spatial scalesPublication . Gómez-Gras, D.; Bensoussan, N.; Ledoux, J. B.; López-Sendino, P.; Cerrano, C.; Ferretti, E.; Kipson, S.; Bakran-Petricioli, T.; A, Serrão; Paulo, D.; Coelho, Márcio; Pearson, Gareth; Boavida, J.; Montero-Serra, I.; Pagès-Escolà, M.; Medrano, A.; López-Sanz, A.; Milanese, M.; Linares, C.; Garrabou, J.Understanding the factors and processes that shape intra-specific sensitivity to heat stress is fundamental to better predicting the vulnerability of benthic species to climate change. Here, we investigate the response of a habitat-forming Mediterranean octocoral, the red gorgonian Paramuricea clavata (Risso, 1826) to thermal stress at multiple biological and geographical scales. Samples from eleven P. clavata populations inhabiting four localities separated by hundreds to more than 1500 km of coast and with contrasting thermal histories were exposed to a critical temperature threshold (25 degrees C) in a common garden experiment in aquaria. Ten of the 11 populations lacked thermotolerance to the experimental conditions provided (25 days at 25 degrees C), with 100% or almost 100% colony mortality by the end of the experiment. Furthermore, we found no significant association between local average thermal regimes nor recent thermal history (i.e., local water temperatures in the 3 months prior to the experiment) and population thermotolerance. Overall, our results suggest that local adaptation and/or acclimation to warmer conditions have a limited role in the response of P. clavata to thermal stress. The study also confirms the sensitivity of this species to warm temperatures across its distributional range and questions its adaptive capacity under ocean warming conditions. However, important inter-individual variation in thermotolerance was found within populations, particularly those exposed to the most severe prior marine heatwaves. These observations suggest that P. clavata could harbor adaptive potential to future warming acting on standing genetic variation (i.e., divergent selection) and/or environmentally-induced phenotypic variation (i.e., intra- and/or intergenerational plasticity).
- First record of Ruppia maritima in West Africa supported by morphological description and phylogenetic classificationPublication . Martínez-Garrido, Jose; Creed, Joel C.; Martins, Samir; Almada, Carmen H.; A, SerrãoRuppia maritima (widgeon grass) has been identified phylogenetically for the first time from West Africa (Santiago Island, Cape Verde). Genetic markers distinguished this species from the tetraploid Ruppia cf. maritima previously known from West Africa. Taxonomic description, photographs and molecular phylogenetic classification are provided here. The results show that, in Cape Verde, the species is phylogenetically closer to European and northeast American than to Indo-Pacific populations. This study extends the known distribution of R. maritima, an ecosystem structuring species that provides essential habitat for threatened animals.
- Global impacts of projected climate changes on the extent and aboveground biomass of mangrove forestsPublication . Gouvêa, Lidiane; A, Serrão; Cavanaugh, Kyle; Gurgel, Carlos F. D.; Horta, Paulo A.; Assis, JorgeAim: Over the past 50 years, anthropogenic activities have led to the disappearance of approximately one-third of the world's mangrove forests and their associated ecosystem services. The synergetic combined effect of projected climate change is likely to further impact mangroves in the years to come, whether by range expansions associated with warming at higher latitudes or large-scale diebacks linked to severe droughts. We provide an estimate of future changes in the extent and aboveground biomass (AGB) of mangrove forests at global scales by considering contrasting Representative Concentration Pathway scenarios (decade 2090-2100 under RCP 2.6 in line with the Paris Agreement expectations, and RCP 8.5 of higher emissions). Location: Global. Methods: Boosted regression trees fitted occurrence and AGB of mangroves against high-resolution biologically meaningful data on air temperature, precipitation, wave energy, slope and distance to river Deltas. Results: On the global scale, models produced for present-day conditions retrieved high accuracy scores and estimated a total area of 12,780,356 ha and overall biomass of 2.29 Pg, in line with previous estimates. Model projections showed poleward shifts along temperate regions, which translated into comparable gains in total area, regardless of the RCP scenario (area change RCP 2.6: 17.29%; RCP 8.5: 15.77%). However, biomass changes were dependent on the emission scenario considered, remaining stable or even increasing under RCP 2.6, or undergoing severe losses across tropical regions under RCP 8.5 (overall biomass change RCP 2.6: 12.97%; RCP 8.5: -11.51%). Such losses were particularly aggravated in countries located in the Tropical Atlantic and Eastern Pacific, and the Western and Eastern Indo-Pacific regions (regions with losses above similar to 20% in overall biomass). Conclusions: Our global estimates highlight the potential effect of future climate changes on mangrove forests and how broad compliance with the Paris Agreement may counteract severe trajectories of loss. The projections made, also provided at the country level, serve as new baselines to evaluate changes in mangrove carbon sequestration and ecosystem services, strongly supporting policy-making and management directives, as well as to guide restoration actions considering potential future changes in niche availability.
- Golden carbon of Sargassum forests revealed as an opportunity for climate change mitigationPublication . Gouvêa, Lidiane P.; Assis, Jorge; Gurgel, Carlos F. D.; A, Serrão; Silveira, Thiago C.L.; Santos, Rui; Duarte, Carlos M.; Peres, Leticia M. C.; Carvalho, Vanessa F.; Batista, Manuela; Bastos, Eduardo; Sissini, Marina N.; Horta, Paulo A.Marine climate change mitigation initiatives have recently attracted a great deal of interest in the role of natural carbon sinks, particularly on coastal systems. Brown seaweeds of the genus Sargassum are the largest canopyforming algae in tropical and subtropical environments, with a wide global distribution on rocky reefs and as floating stands. Because these algae present high amounts of biomass, we suggest their contribution is relevant for global carbon stocks and consequently for mitigating climate change as CO2 remover. We modelled global distributions and quantified carbon stocks as above-ground biomass (AGB) with machine learning algorithms and climate data. Sargassum AGB totaled 13.1 Pg C at the global scale, which is a significant amount of carbon, comparable to other key marine ecosystems, such as mangrove forests, salt marshes and seagrass meadows. However, specific techniques related to bloom production and management, or the utilization of biomass for biomaterials, should be fostered.
- High genetic differentiation of red gorgonian populations from the Atlantic Ocean and the Mediterranean SeaPublication . Pilczynska, Joanna; Cocito, Silvia; boavida, joana; A, Serrão; Queiroga, HenriquePatterns of genetic variation within a species may be used to infer past events in the evolutionary history of marine species. In the present study we aimed to compare the genetic diversity of the red gorgonian Paramuricea clavata in the Atlantic Ocean and the Mediterranean Sea. For genetic markers we used microsatellites and a mitochondrial gene fragment. Our results revealed a distinct genetic composition and diversity between the Mediterranean and the Atlantic. The Mediterranean samples had higher microsatellite heterozygosity, allelic richness and private allelic richness. The hypotheses that can explain these patterns are the isolation of Atlantic populations and/or a founder effect. Additionally, a clear difference was obtained from the mitochondrial locus, since sequences from Atlantic and Mediterranean samples diverged by 1%, which is high for soft corals.
- Major shifts at the range edge of marine forests: the combined effects of climate changes and limited dispersalPublication . Assis, J.; Berecibar, E.; Claro, B.; Alberto, F.; Reed, D.; Raimondi, P.; A, SerrãoGlobal climate change is likely to constrain low latitude range edges across many taxa and habitats. Such is the case for NE Atlantic marine macroalgal forests, important ecosystems whose main structuring species is the annual kelp Saccorhiza polyschides. We coupled ecological niche modelling with simulations of potential dispersal and delayed development stages to infer the major forces shaping range edges and to predict their dynamics. Models indicated that the southern limit is set by high winter temperatures above the physiological tolerance of overwintering microscopic stages and reduced upwelling during recruitment. The best range predictions were achieved assuming low spatial dispersal (5 km) and delayed stages up to two years (temporal dispersal). Reconstructing distributions through time indicated losses of similar to 30% from 1986 to 2014, restricting S. polyschides to upwelling regions at the southern edge. Future predictions further restrict populations to a unique refugium in northwestern Iberia. Losses were dependent on the emissions scenario, with the most drastic one shifting similar to 38% of the current distribution by 2100. Such distributional changes might not be rescued by dispersal in space or time (as shown for the recent past) and are expected to drive major biodiversity loss and changes in ecosystem functioning.
- Population level variation in reproductive development and output in the golden kelp Laminaria ochroleuca under marine heat wave scenariosPublication . Strasser, Fiona-Elaine; Barreto, Luis M.; Kaidi, Soukaina; Sabour, Brahim; A, Serrão; Pearson, Gareth; Martins, NeusaThermal tolerance is often interpreted as a species-wide thermal niche in the absence of studies focusing on the adaptive potential of populations to exhibit differential thermal tolerance. Thus, considering intraspecific thermal plasticity, local adaptation or both between populations along distributional gradients when interpreting and predicting species responses to warming is imperative. Removing the effect of environmental histories by raising kelp gametophyte generations in vitro under common garden conditions allows unbiased comparison between population-specific adaptive variation under different environmental conditions. Following this approach, this study aims to detect (potentially) adaptive differentiation in microscopic life-stages (gametophytes) between populations of a temperate forest forming kelp, Laminaria ochroleuca from locations with distinct thermal conditions. Gametophytes from four geographically distinct populations were subjected to different temperature treatments (17, marine heat waves of 23, 25 and 27 degrees C) and gametophyte survival during thermal stress as well as reproductive success and photosynthetic responses during recovery were investigated. Intraspecific variation in resilience and reproductive output to thermal stress was found in L. ochroleuca; gametophytes from the most northern population (Brittany, France) were the most thermally sensitive, with mortality onset at 23 degrees C, whereas mortality in the remaining populations was only apparent at 27 degrees C. Gametophytes from northern Spain and Morocco exhibited very low reproductive success during recovery from 23 and 25 degrees C. However, when recovering from the highest thermal treatment (27 degrees C) the reproductive development and sporophyte output was higher than in the gametophytes from France and Italy (Mediterranean). The population-specific responses of gametophyte resilience and reproductive success to temperature stress suggest genetic differentiation in response to variation in local thermal regimes.