Homeostatic and Tissue Reparation Defaults in Mice Carrying Selective Genetic Invalidation of CXCL12/Proteoglycan Interactions.

International audienceBACKGROUND: Interaction with heparan sulfate proteoglycans is supposed to provide chemokines with the capacity to immobilize on cell surface and extracellular matrix for accomplishing both tissue homing and signaling of attracted cells. However, the consequences of the exclusive invalidation of such interaction on the roles played by endogenous chemokines in vivo remain unascertained. METHODS AND RESULTS: We engineered a mouse carrying a Cxcl12 gene (Cxcl12(Gagtm)) mutation that precludes interactions with heparan sulfate structures while not affecting CXCR4-dependent cell signaling of CXCL12 isoforms (α, β, γ). Cxcl12(Gagtm/Gagtm) mice develop normally, express normal levels of total and isoform-specific Cxcl12 mRNA, and show increased counting of circulating CD34(+) hematopoietic precursor cells. After induced acute ischemia, a marked impaired capacity to support revascularization was observed in Cxcl12(Gagtm/Gagtm) animals associated with a reduced number of infiltrating cells in the ischemic tissue despite the massive expression of CXCL12 isoforms. Importantly, exogenous administration of CXCL12γ, which binds heparan sulfate with the highest affinity ever reported for a cytokine, fully restores vascular growth, whereas heparan sulfate-binding CXCL12γ mutants failed to promote revascularization in Cxcl12(Gagtm/Gagtm) animals. CONCLUSION: These findings prove the role played by heparan sulfate interactions in the functions of CXCL12 in both homeostasis and physiopathological settings and document for the first time the paradigm of chemokine immobilization in vivo

Neurodevelopment Genes in Lampreys Reveal Trends for Forebrain Evolution in Craniates

The forebrain is the brain region which has undergone the most dramatic changes through vertebrate evolution. Analyses conducted in lampreys are essential to gain insight into the broad ancestral characteristics of the forebrain at the dawn of vertebrates, and to understand the molecular basis for the diversifications that have taken place in cyclostomes and gnathostomes following their splitting. Here, we report the embryonic expression patterns of 43 lamprey genes, coding for transcription factors or signaling molecules known to be involved in cell proliferation, stemcellness, neurogenesis, patterning and regionalization in the developing forebrain. Systematic expression patterns comparisons with model organisms highlight conservations likely to reflect shared features present in the vertebrate ancestors. They also point to changes in signaling systems –pathways which control the growth and patterning of the neuroepithelium-, which may have been crucial in the evolution of forebrain anatomy at the origin of vertebrates

Follistatin Is an Early Player in Rainbow Trout Ovarian Differentiation and Is Both Colocalized with Aromatase and Regulated by the Wnt Pathway.

International audienceIn mammals, follistatin (FST) plays an important role in early ovarian differentiation, acting downstream of the Wnt pathway. In teleost fish, fst is implicated in folliculogenesis and oocyte maturation, and an early and specific expression during ovarian differentiation has been described in rainbow trout, Oncorhynchus mykiss. By in situ hybridization, we demonstrated that during rainbow trout gonadal differentiation, fst shares a similar expression pattern with cyp19a1a, the gene encoding ovarian aromatase, a key steroidogenic enzyme needed for ovarian differentiation in fish. Expression of fst and cyp19a1a was first detected in a few scattered cells in the embryonic ovary several days before hatching. Then, after histological differentiation, fst and cyp19a1a expression was localized in clusters of cells lining the future ovarian lamellae. As FST expression is known to be induced by the Wnt/β-catenin pathway in mammals, the Wnt pathway was inhibited in vivo with the IWR-1 molecule, and we analyzed by qPCR the effects of this treatment on fst expression. We found that IWR-1 decreased fst expression in female gonads, consistent with a regulation of fst expression by the Wnt pathway in rainbow trout. Furthermore, expression of cyp19a1a was also downregulated, suggesting an implication of the Wnt pathway in ovarian differentiation

Caractérisation d'une implication de la stéroïdogenèse dans le processus de différenciation sexuelle de la gonade chez le poisson zèbre <em>(Danio rerio)</em> à des fins d'études écotoxicologiques

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Expression and localization of steroidogenic enzymes during gonadal sexual differentiation in zebrafish

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Cutaneous manifestations of lymphoid-variant hypereosinophilic syndrome

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Coastal high-frequency radars in the Mediterranean - Part 1: Status of operations and a framework for future development

none42Due to the semi-enclosed nature of the Mediterranean Sea, natural disasters and anthropogenic activities impose stronger pressures on its coastal ecosystems than in any other sea of the world. With the aim of responding adequately to science priorities and societal challenges, littoral waters must be effectively monitored with high-frequency radar (HFR) systems. This land-based remote sensing technology can provide, in near-real time, fine-resolution maps of the surface circulation over broad coastal areas, along with reliable directional wave and wind information. The main goal of this work is to showcase the current status of the Mediterranean HFR network and the future roadmap for orchestrated actions. Ongoing collaborative efforts and recent progress of this regional alliance are not only described but also connected with other European initiatives and global frameworks, highlighting the advantages of this cost-effective instrument for the multi-parameter monitoring of the sea state. Coordinated endeavors between HFR operators from different multi-disciplinary institutions are mandatory to reach a mature stage at both national and regional levels, striving to do the following: (i) harmonize deployment and maintenance practices; (ii) standardize data, metadata, and quality control procedures; (iii) centralize data management, visualization, and access platforms; and (iv) develop practical applications of societal benefit that can be used for strategic planning and informed decision-making in the Mediterranean marine environment. Such fit-for-purpose applications can serve for search and rescue operations, safe vessel navigation, tracking of marine pollutants, the monitoring of extreme events, the investigation of transport processes, and the connectivity between offshore waters and coastal ecosystems. Finally, future prospects within the Mediterranean framework are discussed along with a wealth of socioeconomic, technical, and scientific challenges to be faced during the implementation of this integrated HFR regional network.Lorente, P; Aguiar, E; Bendoni, M; Berta, M; Brandini, C; Caceres-Euse, A; Capodici, F; Cianelli, D; Ciraolo, G; Corgnati, L; Dadic, V; Doronzo, B; Drago, A; Dumas, D; Falco, P; Fattorini, M; Gauci, A; Gomez, R; Griffa, A; Guerin, CA; Hernandez-Carrasco, I; Hernandez-Lasheras, J; Licer, M; Magaldi, MG; Mantovani, C; Mihanovic, H; Molcard, A; Mourre, B; Orfila, A; Revelard, A; Reyes, E; Sanchez, J; Saviano, S; Sciascia, R; Taddei, S; Tintore, J; Toledo, Y; Ursella, L; Uttieri, M; Vilibic, I; Zambianchi, E; Cardin, VLorente, P; Aguiar, E; Bendoni, M; Berta, M; Brandini, C; Caceres-Euse, A; Capodici, F; Cianelli, D; Ciraolo, G; Corgnati, L; Dadic, V; Doronzo, B; Drago, A; Dumas, D; Falco, P; Fattorini, M; Gauci, A; Gomez, R; Griffa, A; Guerin, Ca; Hernandez-Carrasco, I; Hernandez-Lasheras, J; Licer, M; Magaldi, Mg; Mantovani, C; Mihanovic, H; Molcard, A; Mourre, B; Orfila, A; Revelard, A; Reyes, E; Sanchez, J; Saviano, S; Sciascia, R; Taddei, S; Tintore, J; Toledo, Y; Ursella, L; Uttieri, M; Vilibic, I; Zambianchi, E; Cardin,

Coastal high-frequency radars in the Mediterranean - Part 2: Applications in support of science priorities and societal needs

none42The Mediterranean Sea is a prominent climate-change hot spot, with many socioeconomically vital coastal areas being the most vulnerable targets for maritime safety, diverse met-ocean hazards and marine pollution. Providing an unprecedented spatial and temporal resolution at wide coastal areas, high-frequency radars (HFRs) have been steadily gaining recognition as an effective land-based remote sensing technology for continuous monitoring of the surface circulation, increasingly waves and occasionally winds. HFR measurements have boosted the thorough scientific knowledge of coastal processes, also fostering a broad range of applications, which has promoted their integration in coastal ocean observing systems worldwide, with more than half of the European sites located in the Mediterranean coastal areas. In this work, we present a review of existing HFR data multidisciplinary science-based applications in the Mediterranean Sea, primarily focused on meeting end-user and science-driven requirements, addressing regional challenges in three main topics: (i) maritime safety, (ii) extreme hazards and (iii) environmental transport process. Additionally, the HFR observing and monitoring regional capabilities in the Mediterranean coastal areas required to underpin the underlying science and the further development of applications are also analyzed. The outcome of this assessment has allowed us to provide a set of recommendations for future improvement prospects to maximize the contribution to extending science-based HFR products into societally relevant downstream services to support blue growth in the Mediterranean coastal areas, helping to meet the UN's Decade of Ocean Science for Sustainable Development and the EU's Green Deal goals.Reyes, E; Aguiar, E; Bendoni, M; Berta, M; Brandini, C; Caceres-Euse, A; Capodici, F; Cardin, V; Cianelli, D; Ciraolo, G; Corgnati, L; Dadic, V; Doronzo, B; Drago, A; Dumas, D; Falco, P; Fattorini, M; Fernandes, MJ; Gauci, A; Gomez, R; Griffa, A; Guerin, CA; Hernandez-Carrasco, I; Hernandez-Lasheras, J; Licer, M; Lorente, P; Magaldi, MG; Mantovani, C; Mihanovic, H; Molcard, A; Mourre, B; Revelard, A; Reyes-Suarez, C; Saviano, S; Sciascia, R; Taddei, S; Tintore, J; Toledo, Y; Uttieri, M; Vilibic, I; Zambianchi, E; Orfila, AReyes, E; Aguiar, E; Bendoni, M; Berta, M; Brandini, C; Caceres-Euse, A; Capodici, F; Cardin, V; Cianelli, D; Ciraolo, G; Corgnati, L; Dadic, V; Doronzo, B; Drago, A; Dumas, D; Falco, P; Fattorini, M; Fernandes, Mj; Gauci, A; Gomez, R; Griffa, A; Guerin, Ca; Hernandez-Carrasco, I; Hernandez-Lasheras, J; Licer, M; Lorente, P; Magaldi, Mg; Mantovani, C; Mihanovic, H; Molcard, A; Mourre, B; Revelard, A; Reyes-Suarez, C; Saviano, S; Sciascia, R; Taddei, S; Tintore, J; Toledo, Y; Uttieri, M; Vilibic, I; Zambianchi, E; Orfila,

Coastal HF radars in the Mediterranean: status of operations and a framework for future development

Abstract. Due to the semi-enclosed nature of the Mediterranean Sea, natural disasters and anthropogenic activities impose stronger pressures on its coastal ecosystems than in any other sea of the world. With the aim of responding adequately to science priorities and societal challenges, littoral waters must be effectively monitored with High-Frequency radar (HFR) systems. This land-based remote sensing technology can provide, in near real-time, fine-resolution maps of the surface circulation over broad coastal areas, along with reliable directional wave and wind information. The main goal of this work is to showcase the current status of the Mediterranean HFR network and the future roadmap for orchestrated actions. Ongoing collaborative efforts and recent progress of this regional alliance are not only described but also connected with other European initiatives and global frameworks, highlighting the advantages of this cost-effective instrument for the multi-parameter monitoring of the sea state. Coordinated endeavours between HFR operators from different multi-disciplinary institutions are mandatory to reach a mature stage at both national and regional levels, striving to: i) harmonize deployment and maintenance practices; ii) standardize data, metadata and quality control procedures; iii) centralize data management, visualization and access platforms; iv) develop practical applications of societal benefit, that can be used for strategic planning and informed decision-making in the Mediterranean marine environment. Such fit-for-purpose applications can serve for search and rescue operations, safe vessel navigation, tracking of marine pollutants, the monitoring of extreme events or the investigation of transport processes and the connectivity between offshore waters and coastal ecosystems. Finally, future prospects within the Mediterranean framework are discussed along with a wealth of socio-economic, technical and scientific challenges to be faced during the implementation of this integrated HFR regional network