Viticulture tropicale dans le monde : caractéristiques et limites climatiques.

La vitiviniculture tropicale affiche une expansion très rapide pour de multiples raisons (économiques, politiques, sanitaires, etc.). Dans l?espace intertropical, l?absence de saison froide permet une croissance continue de la vigne, offrant la possibilité de réaliser plusieurs récoltes par an. Tropical viticulture in the world: climatic characteristics and limits Tropical vitiviniculture is expanding rapidly for a variety of reasons (economic, political, health, etc.). Between the tropics, the absence of a cold season allows a continuous growth of the vine, offering the possibility of making several harvests a year. The beginning of each "vegetative cycle" of the vine is controlled by human intervention, which makes it possible to choose the time of year when the climatic conditions are most favorable to the oenological potential of the grape. But this "flexibility" is not systematic. Viticultura tropicale nel mondo : caratteristiche e limiti climatici La vitivinicultura tropicale mostra una espansione molto rapida a causa di molti fattori (economici, politici, sanitari, etc.). Nello spazio intertropicale , l?assenza della stagione fredda permette una crescita continua della vite, permettendo la realizzazione di piu? raccolti per anno.L?inizio di ogni «ciclo vegetativo» della vite é controllato a traverso l?intervento umano, permettendo quindi di ottimizzare la scelta del periodo,o deiperiodi,dell?anno con le condizioni climatiche il piu favorevole possibile per il potenziale enologico dell?uva.CONGRESO MUNDIAL DE LA VIÑA Y EL VINO, 41., ASEMBLE GENERAL DE LA ORGANIZACIÓN INTERNACIONAL DE LA VIÑA Y EL VINO, 16.,2018, Punta del Este, UR. Anais...Punta Del Este: OIV, 19 al 23 de noviembre 2018. http://www.oiv.int/es/la-organizacion-intenacional-de-la-vina-y-el-vino/congreso-oi

M-ficolin interacts with the long pentraxin PTX3: a novel case of cross-talk between soluble pattern-recognition molecules.

International audienceFicolins and pentraxins are soluble oligomeric pattern-recognition molecules that sense danger signals from pathogens and altered self-cells and might act synergistically in innate immune defense and maintenance of immune tolerance. The interaction of M-ficolin with the long pentraxin pentraxin 3 (PTX3) has been characterized using surface plasmon resonance spectroscopy and electron microscopy. M-ficolin was shown to bind PTX3 with high affinity in the presence of calcium ions. The interaction was abolished in the presence of EDTA and inhibited by N-acetyl-D-glucosamine, indicating involvement of the fibrinogen-like domain of M-ficolin. Removal of sialic acid from the single N-linked carbohydrate of the C-terminal domain of PTX3 abolished the interaction. Likewise, an M-ficolin mutant with impaired sialic acid-binding ability did not interact with PTX3. Interaction was also impaired when using the isolated recognition domain of M-ficolin or the monomeric C-terminal domain of PTX3, indicating requirement for oligomerization of both proteins. Electron microscopy analysis of the M-ficolin-PTX3 complexes revealed that the M-ficolin tetramer bound up to four PTX3 molecules. From a functional point of view, immobilized PTX3 was able to trigger M-ficolin-dependent activation of the lectin complement pathway. These data indicate that interaction of M-ficolin with PTX3 arises from its ability to bind sialylated ligands and thus differs from the binding to the short pentraxin C-reactive protein and from the binding of L-ficolin to PTX3. The M-ficolin-PTX3 interaction described in this study represents a novel case of cross-talk between soluble pattern-recognition molecules, lending further credit to the integrated view of humoral innate immunity that emerged recently

The RNA-binding region of human TRBP interacts with microRNA precursors through two independent domains.

International audienceMicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression through RNA interference. Human miRNAs are generated through a series of enzymatic processing steps. The precursor miRNA (pre-miRNA) is recognized and cleaved by a complex containing Dicer and several non-catalytic accessory proteins. HIV TAR element binding protein (TRBP) is a constituent of the Dicer complex, which augments complex stability and potentially functions in substrate recognition and product transfer to the RNA-induced silencing complex. Here we have analysed the interaction between the RNA-binding region of TRBP and an oncogenic human miRNA, miR-155, at different stages in the biogenesis pathway. We show that the region of TRBP that binds immature miRNAs comprises two independent double-stranded RNA-binding domains connected by a 60-residue flexible linker. No evidence of contact between the two double-stranded RNA-binding domains was observed either in the apo- or RNA-bound state. We establish that the RNA-binding region of TRBP interacts with both pre-miR-155 and the miR-155/miR-155* duplex through the same binding surfaces and with similar affinities, and that two protein molecules can simultaneously interact with each immature miRNA. These data suggest that TRBP could play a role before and after processing of pre-miRNAs by Dicer

The CO dehydrogenase accessory protein CooT is a novel nickel-binding protein.

International audienceIn Rhodospirillum rubrum, maturation of Carbon Monoxide Dehydrogenase (CODH) requires three accessory proteins, CooC, CooT and CooJ, dedicated to nickel insertion into the active site, which is constituted by a distorted [NiFe$_3$S$_4$] cubane coordinated with a mononuclear Fe site. CooC is an ATPase proposed to provide the energy required for the maturation process, while CooJ is described as a metallochaperone with 16 histidines and 2 cysteines at the C-terminus, likely involved in metal binding and/or storage. Prior to the present study, no information was available on CooT at the molecular level. Here, the X-ray structure of RrCooT was obtained, which revealed that this protein is a homodimer featuring a fold that resembles an Sm-like domain, suggesting a role in RNA metabolism that was however not supported by experimental observations. Biochemical and biophysical evidence based on circular dichroism spectroscopy, light scattering, isothermal titration calorimetry and site-directed mutagenesis showed that RrCooT specifically binds a single Ni(ii) per dimer, with a dissociation constant of 9 nM, through the pair of Cys2, highly conserved residues, located at the dimer interface. Despite its role in the activation of RrCODH in vivo, CooT was thought to be a unique protein, found only in R. rubrum, with an unclear function. In this study, we extended the biological impact of CooT, establishing that this protein is a member of a novel Ni(ii)-binding protein family with 111 homologues, linked to anaerobic metabolism in bacteria and archaea, and in most cases to the presence of CODH