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Members of the ERF Family of Transcription Factors play an important role in plant development and gene expression that regulates responses to biotic and abiotic stress. This work identified 36 ERF family genes in Coffea arabica within the AP2/ERF full domain, using the EST-based genomic resource of the Brazilian Coffee Genome Project. The ERF family genes were classified into nine of the ten existing groups through phylogenetic analysis of the deduced amino acid sequences and comparison with the sequences of the ERF family genes in Arabidopsis. In addition to the AP2 domain, other conserved domains were identified, typical of members of each group. The in silico analysis and expression profiling showed high levels of expression for libraries derived from tissues of fruits, leaves and flowers as well as for libraries subjected to water stress. These results suggest the participation of the ERF family genes of C. arabica in distinct biological functions, such as control of development, maturation, and responses to water stress. The results of this work imply in the selection of promising genes for further functional characterizations that will provide a better understanding of the complex regulatory networks related to plant development and responses to stress, opening up opportunities for coffee breeding programs.

Members of the ERF Family of Transcription Factors play an important role in plant development and gene expression that regulates responses to biotic and abiotic stress. This work identified 36 ERF family genes in Coffea arabica within the AP2/ERF full domain, using the EST-based genomic resource of the Brazilian Coffee Genome Project. The ERF family genes were classified into nine of the ten existing groups through phylogenetic analysis of the deduced amino acid sequences and comparison with the sequences of the ERF family genes in Arabidopsis. In addition to the AP2 domain, other conserved domains were identified, typical of members of each group. The in silico analysis and expression profiling showed high levels of expression for libraries derived from tissues of fruits, leaves and flowers as well as for libraries subjected to water stress. These results suggest the participation of the ERF family genes of C. arabica in distinct biological functions, such as control of development, maturation, and responses to water stress. The results of this work imply in the selection of promising genes for further functional characterizations that will provide a better understanding of the complex regulatory networks related to plant development and responses to stress, opening up opportunities for coffee breeding programs. Made available in DSpace on 2022-01-25T14:00:24Z (GMT). No. of bitstreams: 1 Identification-structure-2021.pdf: 961372 bytes, checksum: 09afa2ecc28963b2b125eb169adf4cd5 (MD5) Previous issue date: 2021

Le Centre culturel de Vanuatu veille a la preservation et a la transmission de la culture traditionnelle de l’archipel : la kastom. Le savoir se partage entre fieldworkers et conservateurs pour gerer, exposer et constituer leur patrimoine materiel et immateriel.

Bernadac Marie-laure. Barthélémy Toguo, «Célébrations» 2017. In: Sèvres. Revue de la Société des Amis du musée national de Céramique, n°27, 2018. pp. 154-159.

International audience; Survival biomass production and crop yield are heavily constrained by a wide range of environmental stresses. Several phytohormones among which abscisic acid (ABA), ethylene and salicylic acid (SA) are known to mediate plant responses to these stresses. By contrast, the role of the plant hormone auxin in stress responses remains so far poorly studied. Auxin controls many aspects of plant growth and development, and Auxin Response Factors play a key role in the transcriptional activation or repression of auxin-responsive genes through direct binding to their promoters. As a mean to gain more insight on auxin involvement in a set of biotic and abiotic stress responses in tomato, the present study uncovers the expression pattern of SlARF genes in tomato plants subjected to biotic and abiotic stresses. In silico mining of the RNAseq data available through the public TomExpress web platform, identified several SlARFs as responsive to various pathogen infections induced by bacteria and viruses. Accordingly, sequence analysis revealed that 5’ regulatory regions of these SlARFs are enriched in biotic and abiotic stress-responsive cis-elements. Moreover, quantitative qPCR expression analysis revealed that many SlARFs were differentially expressed in tomato leaves and roots under salt, drought and flooding stress conditions. Further pointing to the putative role of SlARFs in stress responses, quantitative qPCR expression studies identified some miRNA precursors as potentially involved in the regulation of their SlARF target genes in roots exposed to salt and drought stresses. These data suggest an active regulation of SlARFs at the post-transcriptional level under stress conditions. Based on the substantial change in the transcript accumulation of several SlARF genes, the data presented in this work strongly support the involvement of auxin in stress responses thus enabling to identify a set of candidate SlARFs as potential mediators of biotic and abiotic stress responses.

A gene encoding an elongation factor LeEF-Tsmt that participates in the protein synthesis process in mitochondria shows strong expression in ripening fruit as compared to other organs. It is strongly up-regulated during the first stages of the ripening process in parallel with the climacteric rise in respiration. LeEF-Tsmt expression is stimulated by ethylene, wounding and high temperature but ethylene-insensitive mutants exhibit normal expression. Transgenic fruit have been generated in which LeEF-Tsmt has been constitutively up- and down-regulated. Surprisingly, altering the expression of the gene by genetic transformation with antisense and sense LeEF-Tsmt constructs did not affect the pattern of respiration and ethylene production during ripening and upon wounding. In addition, expression of the alternative oxidase gene which is known to play an important role in respiratory climacteric was not affected. Possible reasons for the absence of effect on respiration of variations of LeEF-Tsmt gene expression are discussed. Made available in DSpace on 2016-10-25T21:37:34Z (GMT). No. of bitstreams: 1 GIRARDIOstharvestBiolTechv42n1p12006.pdf: 466398 bytes, checksum: 9306c559caab243abde7e824345aea9c (MD5) Previous issue date: 2012-08-06

Summary Flagella of some pathogens or marine microbes are sheathed by an apparent extension of the outer cell membrane. Although flagellar sheath has been reported for almost 60 years, little is known about its function and the mechanism of its assembly. Recently, we have observed a novel type of sheath that encloses a flagellar bundle, instead of a single flagellum, in a marine magnetotactic bacterium MO-1. Here, we reported isolation and characterization of the sheath which can be described as a six-start, right-handed helical tubular structure with a diameter of about 100 nm, and a pitch of helix of about 260 nm. By proteomic, microscopic and immunolabelling analyses, we showed that the sheath of MO-1 consists of glycoprotein with an apparent molecular mass > 350 kDa. This protein, named sheath-associated protein (Sap), shows homology with bacterial adhesins and eukaryotic calcium-dependent adherent proteins (cadherin). Most importantly, we showed that calcium ions mediate the assembly of the tubular-shaped sheath and disintegration of the sheath was deleterious for smooth swimming of MO-1 cells. The disintegrated sheath was efficiently reconstituted in vitro by adding calcium ions. Altogether, these results demonstrate a novel bacterial Ca2+-dependent surface architecture, which is essential for bacterial swimming.

Mimivirus, a virus infecting Acanthamoeba, is the prototype of the Mimiviridae, the latest addition to the nucleocytoplasmic large DNA viruses. The Mimivirus genome encodes close to 1000 proteins, many of them never before encountered in a virus, such as four amino-acyl tRNA synthetases. To explore the physiology of this exceptional virus and identify the genes involved in the building of its characteristic intracytoplasmic “virion factory,” we coupled electron microscopy observations with the massively parallel pyrosequencing of the polyadenylated RNA fractions of Acanthamoeba castellanii cells at various time post-infection. We generated 633,346 reads, of which 322,904 correspond to Mimivirus transcripts. This first application of deep mRNA sequencing (454 Life Sciences [Roche] FLX) to a large DNA virus allowed the precise delineation of the 5′ and 3′ extremities of Mimivirus mRNAs and revealed 75 new transcripts including several noncoding RNAs. Mimivirus genes are expressed across a wide dynamic range, in a finely regulated manner broadly described by three main temporal classes: early, intermediate, and late. This RNA-seq study confirmed the AAAATTGA sequence as an early promoter element, as well as the presence of palindromes at most of the polyadenylation sites. It also revealed a new promoter element correlating with late gene expression, which is also prominent in Sputnik, the recently described Mimivirus “virophage.” These results—validated genome-wide by the hybridization of total RNA extracted from infected Acanthamoeba cells on a tiling array (Agilent)—will constitute the foundation on which to build subsequent functional studies of the Mimivirus/Acanthamoeba system.

De nombreuses études épidémiologiques réalisées auprès de groupes de personnes travaillant dans le secteur agricole mettent en évidence une association entre les expositions aux pesticides et certaines pathologies chroniques. Une expertise collective de l’Inserm publiée en 2013 a synthétisé la littérature épidémiologique et toxicologique dans ce domaine à l’échelle internationale, de manière à proposer des niveaux de présomption concernant le lien entre expositions aux pesticides et différentes pathologies parmi lesquelles figurent notamment certains cancers (hémopathies malignes, cancers de la prostate, tumeurs cérébrales, cancers cutanés...), certaines maladies neurologiques (maladie de Parkinson, maladie d’Alzheimer, troubles cognitifs...), et certains troubles de la reproduction et du développement. D’autres pathologies suscitent également des interrogations telles que les maladies respiratoires, les troubles immunologiques, les pathologies endocriniennes. De plus, le Centre international de recherche sur le cancer (CIRC) a défini en 2014 des priorités d’évaluation scientifique pour une quinzaine de pesticides sur la période 2015-2019, en considérant notamment que des données scientifiques nouvelles concernant des effets sur l’homme de ces substances avaient été produites.

De nombreuses études épidémiologiques réalisées auprès de groupes de personnes travaillant dans le secteur agricole mettent en évidence une association entre les expositions aux pesticides et certaines pathologies chroniques. Une expertise collective de l’Inserm publiée en 2013 a synthétisé la littérature épidémiologique et toxicologique dans ce domaine à l’échelle internationale, de manière à proposer des niveaux de présomption concernant le lien entre expositions aux pesticides et différentes pathologies parmi lesquelles figurent notamment certains cancers (hémopathies malignes, cancers de la prostate, tumeurs cérébrales, cancers cutanés...), certaines maladies neurologiques (maladie de Parkinson, maladie d’Alzheimer, troubles cognitifs...), et certains troubles de la reproduction et du développement. D’autres pathologies suscitent également des interrogations telles que les maladies respiratoires, les troubles immunologiques, les pathologies endocriniennes. De plus, le Centre international de recherche sur le cancer (CIRC) a défini en 2014 des priorités d’évaluation scientifique pour une quinzaine de pesticides sur la période 2015-2019, en considérant notamment que des données scientifiques nouvelles concernant des effets sur l’homme de ces substances avaient été produites.

De nombreuses études épidémiologiques réalisées auprès de groupes de personnes travaillant dans le secteur agricole mettent en évidence une association entre les expositions aux pesticides et certaines pathologies chroniques. Une expertise collective de l’Inserm publiée en 2013 a synthétisé la littérature épidémiologique et toxicologique dans ce domaine à l’échelle internationale, de manière à proposer des niveaux de présomption concernant le lien entre expositions aux pesticides et différentes pathologies parmi lesquelles figurent notamment certains cancers (hémopathies malignes, cancers de la prostate, tumeurs cérébrales, cancers cutanés...), certaines maladies neurologiques (maladie de Parkinson, maladie d’Alzheimer, troubles cognitifs...), et certains troubles de la reproduction et du développement. D’autres pathologies suscitent également des interrogations telles que les maladies respiratoires, les troubles immunologiques, les pathologies endocriniennes. De plus, le Centre international de recherche sur le cancer (CIRC) a défini en 2014 des priorités d’évaluation scientifique pour une quinzaine de pesticides sur la période 2015-2019, en considérant notamment que des données scientifiques nouvelles concernant des effets sur l’homme de ces substances avaient été produites.

De nombreuses études épidémiologiques réalisées auprès de groupes de personnes travaillant dans le secteur agricole mettent en évidence une association entre les expositions aux pesticides et certaines pathologies chroniques. Une expertise collective de l’Inserm publiée en 2013 a synthétisé la littérature épidémiologique et toxicologique dans ce domaine à l’échelle internationale, de manière à proposer des niveaux de présomption concernant le lien entre expositions aux pesticides et différentes pathologies parmi lesquelles figurent notamment certains cancers (hémopathies malignes, cancers de la prostate, tumeurs cérébrales, cancers cutanés...), certaines maladies neurologiques (maladie de Parkinson, maladie d’Alzheimer, troubles cognitifs...), et certains troubles de la reproduction et du développement. D’autres pathologies suscitent également des interrogations telles que les maladies respiratoires, les troubles immunologiques, les pathologies endocriniennes. De plus, le Centre international de recherche sur le cancer (CIRC) a défini en 2014 des priorités d’évaluation scientifique pour une quinzaine de pesticides sur la période 2015-2019, en considérant notamment que des données scientifiques nouvelles concernant des effets sur l’homme de ces substances avaient été produites.

De nombreuses études épidémiologiques réalisées auprès de groupes de personnes travaillant dans le secteur agricole mettent en évidence une association entre les expositions aux pesticides et certaines pathologies chroniques. Une expertise collective de l’Inserm publiée en 2013 a synthétisé la littérature épidémiologique et toxicologique dans ce domaine à l’échelle internationale, de manière à proposer des niveaux de présomption concernant le lien entre expositions aux pesticides et différentes pathologies parmi lesquelles figurent notamment certains cancers (hémopathies malignes, cancers de la prostate, tumeurs cérébrales, cancers cutanés...), certaines maladies neurologiques (maladie de Parkinson, maladie d’Alzheimer, troubles cognitifs...), et certains troubles de la reproduction et du développement. D’autres pathologies suscitent également des interrogations telles que les maladies respiratoires, les troubles immunologiques, les pathologies endocriniennes. De plus, le Centre international de recherche sur le cancer (CIRC) a défini en 2014 des priorités d’évaluation scientifique pour une quinzaine de pesticides sur la période 2015-2019, en considérant notamment que des données scientifiques nouvelles concernant des effets sur l’homme de ces substances avaient été produites.

De nombreuses études épidémiologiques réalisées auprès de groupes de personnes travaillant dans le secteur agricole mettent en évidence une association entre les expositions aux pesticides et certaines pathologies chroniques. Une expertise collective de l’Inserm publiée en 2013 a synthétisé la littérature épidémiologique et toxicologique dans ce domaine à l’échelle internationale, de manière à proposer des niveaux de présomption concernant le lien entre expositions aux pesticides et différentes pathologies parmi lesquelles figurent notamment certains cancers (hémopathies malignes, cancers de la prostate, tumeurs cérébrales, cancers cutanés...), certaines maladies neurologiques (maladie de Parkinson, maladie d’Alzheimer, troubles cognitifs...), et certains troubles de la reproduction et du développement. D’autres pathologies suscitent également des interrogations telles que les maladies respiratoires, les troubles immunologiques, les pathologies endocriniennes. De plus, le Centre international de recherche sur le cancer (CIRC) a défini en 2014 des priorités d’évaluation scientifique pour une quinzaine de pesticides sur la période 2015-2019, en considérant notamment que des données scientifiques nouvelles concernant des effets sur l’homme de ces substances avaient été produites.

Pseudomonas aeruginosa cytotoxicity is linked to a type III secretion system (T3SS) that delivers effectors into the host cell. We show here that a negative cross-control exists between T3SS and flagellar assembly. We observed that, in a strain lacking flagella, T3SS gene expression, effector secretion, and cytotoxicity were increased. Conversely, we revealed that flagellar-gene expression and motility were decreased in a strain overproducing ExsA, the T3SS master regulator. Interestingly, a nonmotile strain lacking the flagellar filament (Δ fliC ) presented a hyperefficient T3SS and a nonmotile strain assembling flagella (Δ motAB ) did not. More intriguingly, a strain lacking motCD genes is a flagellated strain with a slight defect in swimming. However, in this strain, T3SS gene expression was up-regulated. These results suggest that flagellar assembly and/or mobility antagonizes the T3SS and that a negative cross talk exists between these two systems. An illustration of this is the visualization by electron microscopy of T3SS needles in a nonmotile P. aeruginosa strain, needles which otherwise are not detected. The molecular basis of the cross talk is complex and remains to be elucidated, but proteins like MotCD might have a crucial role in signaling between the two processes. In addition, we found that the GacA response regulator negatively affects the T3SS. In a gacA mutant, the T3SS effector ExoS is hypersecreted. Strikingly, GacA was previously reported as a positive regulator for motility. Globally, our data document the idea that some virulence factors are coordinately but inversely regulated, depending on the bacterial colonization phase and infection types.