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As an evolutionary ancient component of the metazoan immune defense toolkit, the complement system can modulate cells and humoral responses of both innate and (in jawed vertebrates) adaptive immunity. All the three known complement-activation pathways converge on the cleavage of C3 to C3a and C3b. The anaphylatoxin C3a behaves as a chemokine in inflammatory responses, whereas C3b exerts an opsonic role and, ultimately, can activate the lytic pathway. C3aR, one of the mammalian receptors for C3a, is a member of the G-protein-coupled receptor family sharing seven transmembrane alpha helixes. C3aR can act as a chemokine and recruit neutrophils, triggering degranulation and respiratory burst, which initiates an inflammatory reaction. Mining the transcriptome of the colonial ascidian Botryllus schlosseri, we identified a transcript showing homology with both mammalian C3aR and C5aR. The gene (bsc3/c5ar) is actively transcribed in morula cells, the circulating immunocyte triggering the inflammatory reactions in response to the recognition of nonself. Its transcription is modulated during the recurrent cycles of asexual reproduction known as blastogenetic cycles. Moreover, the treatment of hemocytes with C3aR agonist, induces a significant increase in the transcription of BsC3, revealing the presence of an autocrine feedback system able to modulate the expression of C3 in order to obtain a rapid clearance of potentially dangerous nonself cells or particles. The obtained results support the previously proposed role of complement as one of the main humoral components of the immune response in tunicates and stress the importance of morula cells in botryllid ascidian innate immunity.European sea bass is a marine teleost which can inhabit a broad range of environmental salinities. So far, no research has studied the physiological response of this fish to salinity challenges using modifications in skin mucus as a potential biological matrix. Here, we used a skin mucus sampling technique to evaluate the response of sea bass to several acute osmotic challenges (for 3 h) from seawater (35‱) to two hypoosmotic environments, diluted brackish water (3‱) and estuarine waters (12‱), and to one hyperosmotic condition (50‱). For this, we recorded the volume of mucus exuded and compared the main stress-related biomarkers and osmosis-related parameters in skin mucus and plasma. Sea bass exuded the greatest volume of skin mucus with the highest total contents of cortisol, glucose, and protein under hypersalinity. This indicates an exacerbated acute stress response with possible energy losses if the condition is sustained over time. Under hyposalinity, the response depended on the magnitude of the osmotic change shifting to 3‱ was an extreme salinity change, which affected fish aerobic metabolism by acutely modifying lactate exudation. All these data enhance the current scarce knowledge of skin mucus as a target through which to study environmental changes and fish status.Minimally processed ready-to-eat (RTE) vegetables are increasingly consumed for their health benefits. However, they also pose a risk of being ingested with food-borne pathogens. The present study investigated the ability of RTE spinach and rocket to support the growth of Listeria monocytogenes as previous studies provided contradicting evidence. Findings were compared to growth on iceberg lettuce that has repeatedly been shown to support growth. Products were inoculated with a three-strain mix of L. monocytogenes at 10 and 100 cfu g-1 and stored in modified atmosphere (4 kPa O2, 8 kPa CO2) at 8 °C over 7-9 days. Spinach demonstrated the highest growth potential rate of 2 to 3 log10 cfu g-1 over a 9-day period with only marginal deterioration in its visual appearance. Growth potential on rocket was around 2 log10 cfu g-1 over 9 days with considerable deterioration in visual appearance. Growth potential of iceberg lettuce was similar to that of rocket over a 7-day period. Growth curves fitted closely to a linear growth model, indicating none to limited restrictions of growth over the duration of storage. The high growth potentials of L. MF-438 research buy monocytogenes on spinach alongside the limited visual deterioration highlight the potential risks of consuming this raw RTE food product when contaminated.Shiitake mushroom (Lentinula edodes) is commonly consumed worldwide and is cultivated in many farms in Korea using Chinese substrates owing to a lack of knowledge on how to prepare sawdust-based substrate blocks (bag cultivation). Consequently, issues related to the origin of the Korean or Chinese substrate used in shiitake mushrooms produced using bag cultivation have been reported. Here, we investigated differences in fatty acids (FAs) and stable isotope ratios (SIRs) in shiitake mushrooms cultivated using Korean and Chinese substrates under similar conditions (strain, temperature, humidity, etc.) and depending on the harvesting cycle. The total FA level decreased significantly by 5.49 mg∙g-1 as the harvesting cycle increased (p less then 0.0001); however, no differences were found in FAs between shiitake mushrooms cultivated using Korean and Chinese substrates. Linoleic acid was the most abundant FA, accounting for 77-81% of the total FAs during four harvesting cycles. Moreover, the SIRs differed significantly between the Korean and Chinese substrates, and the harvesting cycles resulted in smaller maximum differences in SIR values compared to those of the cultivation substrate origins. Our findings contribute to the identification of the geographical origin of shiitake mushrooms and may have potential applications in international shiitake-mushroom markets.Calmodulin binding is a nearly universal property of gap junction proteins, imparting a calcium-dependent uncoupling behavior that can serve in an emergency to decouple a stressed cell from its neighbors. However, gap junctions that function as electrical synapses within networks of neurons routinely encounter large fluctuations in local cytoplasmic calcium concentration; frequent uncoupling would be impractical and counterproductive. We have studied the properties and functional consequences of calmodulin binding to the electrical synapse protein Connexin 35 (Cx35 or gjd2b), homologous to mammalian Connexin 36 (Cx36 or gjd2). We find that specializations in Cx35 calmodulin binding sites make it relatively impervious to moderately high levels of cytoplasmic calcium. Calmodulin binding to a site in the C-terminus causes uncoupling when calcium reaches low micromolar concentrations, a behavior prevented by mutations that eliminate calmodulin binding. However, milder stimuli promote calcium/calmodulin-dependent protein kinase II activity that potentiates coupling without interference from calmodulin binding.