In the course of this century, rising anthropogenic CO₂ emissions will likely cause a decrease in ocean pH, know as ocean acidification, together with an increase of water temperature. Only in the ...last years, studies have focused on synergetic effects of both stressors on marine invertebrates, particularly on early life stages considered more vulnerable. Disparate responses of their singular and combined effects were reported, highlighting the importance of extending the studies to different species and populations of marine invertebrates. Here, we observed the response of important parameters such as growth, mortality and oxygen consumption of juvenile pen shell Pinna nobilis at supplied pCO₂ gas levels of 400 ppm (ambient) and 1000 ppm and at three temperatures (20, 23 and 26 °C) during 36 days. To our knowledge, this is the first study on ocean acidification and temperature effects on juveniles of this species. We show that the two stressors play roles at distinct levels, with pCO₂ influencing growth and partially mortality, and temperature increasing mortality rates and oxygen consumption strongly. Therefore, juveniles of P. nobilis are more likely affected by increasing temperature than the pCO₂ levels expected by the end of the twenty-first century.
Predicted pH decreases in ocean surface waters of ~0.3-0.5 and 0.7-0.8 pH units (for 2100 and 2300, respectively) are expected to negatively affect calcification processes and physiological ...performances of many marine organisms. Here we evaluated the response of important parameters such as growth, mortality, oxygen consumption, and mineralization of transplanted Pinna nobilis juveniles in the naturally acidified waters of a CO sub(2) vent system. Our field experiments show a general decrease of physiological responses of juveniles for the studied parameters along a decreasing pH gradient, even if significant effects are only observed under pH values of 7.6 units ("extreme" pH). In particular, the mortality rate increased from 10-30 % over the study period at control conditions to 60-70 % at extreme pH values. We conclude that near-future decreases in pH (decreases of 0.3-0.5 pH units) may not have a significant effect on performance of P. nobilis juveniles, while predicted longer-term decreases (decreases of 0.7-0.8 pH units) could affect the survival of the species. The combination of laboratory experiments with the assessment of naturally acidified environments can provide further insights into the threshold pH affecting the performance of vulnerable marine species.
The Mediterranean basin is one of the regions heavily affected by jellyfish bloom phenomena, mainly due to the presence of scyphozoans, such as
. The jellyfish have few natural predators, and their ...bodies represent an organic-rich substrate that can support rapid bacterial growth with great impact on the structure of marine food webs. In Asiatic countries, jellyfish are widely studied for their health benefits, but their nutritional and nutraceutical values still remain poorly characterized. In this study, the differences in the
H NMR spectroscopy metabolic profiles of
female gonads and body fractions (including umbrella and oral arms), in different sampling periods, were studied. For each body compartment both lipid and aqueous extracts were characterized and their
H NMR metabolic profiles subjected to multivariate analysis. From a statistical analysis of the extracts, a higher contents of ω-3 polyunsaturated fatty acids (PUFAs), amino acid and osmolytes (homarine, betaine, taurine) with important roles in marine invertebrates were observed in female gonads, whereas umbrella and oral arms showed similar metabolic profiles. These results support a sustainable exploitation of the jellyfish for the extraction of bioactive compounds useful in nutraceutical, nutricosmetics, and functional food fields.
The pen shell Pinna nobilis (also known as the fan mussel) is an endemic bivalve of the Mediterranean Sea. Threatened by human activities, it has been listed as an endangered and protected species ...under the European Council Directive 92/43/EEC since 1992. The ecological role of this species is of importance because it filters and retains large amounts of organic matter from suspended detritus contributing to water clarity. In addition, as a hard substrate in the soft-bottom seafloor, it provides a surface that can be colonized by other (floral and faunal) benthic species. Here, we provide an overview of all available published studies on the pen shell, compiling available data and summarizing current knowledge on the conservation status and viability of populations over the full range of the Mediterranean Basin. Additionally, we discuss the different practices in applied methodology and identify gaps and new research areas in order to render conservation programmes of the species more effective.
Under future increased CO
concentrations, seagrasses are predicted to perform better as a result of increased photosynthesis, but the effects in carbon balance and growth are unclear and remain ...unexplored for early life stages such as seedlings, which allow plant dispersal and provide the potential for adaptation under changing environmental conditions. Furthermore, the outcome of the concomitant biochemical changes in plant-herbivore interactions has been poorly studied, yet may have important implications in plant communities. In this study we determined the effects of experimental exposure to current and future predicted CO
concentrations on the physiology, size and defense strategies against herbivory in the earliest life stage of the Mediterranean seagrass Posidonia oceanica. The photosynthetic performance of seedlings, assessed by fluorescence, improved under increased pCO
conditions after 60 days, although these differences disappeared after 90 days. Furthermore, these plants exhibited bigger seeds and higher carbon storage in belowground tissues, having thus more resources to tolerate and recover from stressors. Of the several herbivory resistance traits measured, plants under high pCO
conditions had a lower leaf N content but higher sucrose. These seedlings were preferred by herbivorous sea urchins in feeding trials, which could potentially counteract some of the positive effects observed.
Main conclusion
The ex vitro hairy root system from petioles of detached soybean leaves allows the functional validation of genes using classical transgenesis and CRISPR strategies (e.g., sgRNA ...validation, gene activation) associated with nematode bioassays.
Agrobacterium rhizogenes
-mediated root transformation has been widely used in soybean for the functional validation of target genes in classical transgenesis and single-guide RNA (sgRNA) in CRISPR-based technologies. Initial data showed that in vitro hairy root induction from soybean cotyledons and hypocotyls were not the most suitable strategies for simultaneous performing genetic studies and nematode bioassays. Therefore, an ex vitro hairy root system was developed for in planta screening of target molecules during soybean parasitism by root-knot nematodes (RKNs). Applying this method, hairy roots were successfully induced by
A. rhizogenes
from petioles of detached soybean leaves. The soybean
GmPR10
and
GmGST
genes were then constitutively overexpressed in both soybean hairy roots and tobacco plants, showing a reduction in the number of
Meloidogyne incognita
-induced galls of up to 41% and 39%, respectively. In addition, this system was evaluated for upregulation of the endogenous
GmExpA
and
GmExpLB
genes by CRISPR/dCas9, showing high levels of gene activation and reductions in gall number of up to 58.7% and 67.4%, respectively. Furthermore, morphological and histological analyses of the galls were successfully performed. These collective data validate the ex vitro hairy root system for screening target genes, using classical overexpression and CRISPR approaches, directly in soybean in a simple manner and associated with nematode bioassays. This system can also be used in other root pathosystems for analyses of gene function and studies of parasite interactions with plants, as well as for other purposes such as studies of root biology and promoter characterization.
Hematopoietic stem/progenitor cells (HSPCs) are capable of supporting the lifelong production of blood cells exerting a wide spectrum of functions. Lentiviral vector HSPC gene therapy generates a ...human hematopoietic system stably marked at the clonal level by vector integration sites (ISs). Using IS analysis, we longitudinally tracked >89,000 clones from 15 distinct bone marrow and peripheral blood lineages purified up to 4 years after transplant in four Wiskott-Aldrich syndrome patients treated with HSPC gene therapy. We measured at the clonal level repopulating waves, populations' sizes and dynamics, activity of distinct HSPC subtypes, contribution of various progenitor classes during the early and late post-transplant phases, and hierarchical relationships among lineages. We discovered that in-vitro-manipulated HSPCs retain the ability to return to latency after transplant and can be physiologically reactivated, sustaining a stable hematopoietic output. This study constitutes in vivo comprehensive tracking in humans of hematopoietic clonal dynamics during the early and late post-transplant phases.
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•Hematopoietic reconstitution occurs in two distinct clonal waves•A few thousand HSPC clones stably sustain multilineage blood cell production•Steady-state hematopoiesis after transplant is maintained by both HSCs and MPPs•Natural killer clones have closer relationships to myeloid cells than to lymphoid cells
Biasco et al. report a clonal tracking study on the dynamics and nature of hematopoietic reconstitution in humans after transplant. Using integration sites as molecular tags, they measured, in gene therapy patients, repopulating waves, population size and dynamics, activity of progenitor subtypes during the early and late post-transplant phases, and hierarchical relationships among lineages.
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