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.
Sl-ERF.B.3 (Solanum lycopersicum ethylene response factor B.3) gene encodes for a tomato transcription factor of the ERF (ethylene responsive factor) family. Our results of real-time RT-PCR showed ...that Sl-ERF.B.3 is an abiotic stress responsive gene, which is induced by cold, heat, and flooding, but downregulated by salinity and drought. To get more insight into the role of Sl-ERF.B.3 in plant response to separate salinity and cold, a comparative study between wild type and two Sl-ERF.B.3 antisense transgenic tomato lines was achieved. Compared with wild type, Sl-ERF.B.3 antisense transgenic plants exhibited a salt stress dependent growth inhibition. This inhibition was significantly enhanced in shoots but reduced in roots, leading to an increased root to shoot ratio. Furthermore, the cold stress essay clearly revealed that introducing antisense Sl-ERF.B.3 in transgenic tomato plants reduces their cell injury and enhances their tolerance against 14 d of cold stress. All these results suggest that Sl-ERF.B.3 gene is involved in plant response to abiotic stresses and may play a role in the layout of stress symptoms under cold stress and in growth regulation under salinity.
•ERFs display differential expression in response to different abiotic stresses.•Responses to different types of abiotic stresses can involve common ERFs to set up adaptive strategy.•High and low ...temperature stresses activate different set of ERFs than those activated under water, flooding or salt stresses.•ERFs regulate expression of abiotic stress genes regardless of the presence of GCC or DRE cis-elements in their promoter.
Plants are sessile organisms, hence to face environmental constrains they developed strategies that rely on the activation of stress-response genes under the control of specific transcription factors. The plant hormone ethylene mediates physiological, developmental and stress responses through the activation of Ethylene Response Factors (ERFs) which belong to a large multigene family of transcription factors. While an increasing number of studies supports the involvement of ERFs in abiotic stress responses, so far the specific role of ERF family members in different abiotic stress conditions remains unexplored. The present work investigates the expression profile of a set of ERFs, representative of different ERF types, in tomato plants subjected to cold, heat, salt, drought and flooding conditions. The study revealed that a group of ERFs is preferentially associated with cold and heat stress responses while another set is expressed in response to salt, water and flooding stresses. Transactivation assays indicated that ERFs can regulate the expression of abiotic stress genes regardless of whether or not they harbor conserved GCC or DRE cis-elements in their promoter region. The outcome of the study provides clue on which ERFs should be targeted when aiming to improve adaptation to a particular stress type.
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.
Experienced in psychomotricity in two nursing homes, pony-assisted therapy shows first positive effects on psycho-behavioral symptoms. Recognized in the field of disability and psychiatry, this form ...of therapy is not developed in gerontology.
To measure the effects of this therapy on the behavior of elderly people with neurocognitive disorders living in long-term care and especially on the involvement in this activity. Anxiety and apathy were chosen as the measurement criteria.
An intervention study with an experimental cross-study design was conducted over two months for 23 subjects. An intervention group was studied during a period with TAP and a period without TAP. Another group without intervention was also studied. All participants were assessed before and after intervention with the NPI-R scale. The engagement during two TAP sessions and one animation time was also evaluated with the ECPAI scale.
In the crossover study, positive engagement is more important in participant/pony interaction than in participant/facilitator interaction (p<0.01). The ECPAI score reflecting apathetic behavior was significantly decreased during interaction with the animal than in the interaction with the facilitator in patients undergoing therapy (p<0.01). The ECPAI score reflecting engagement is greater in pony interaction for participants in therapy than in the control group in facilitator interaction (p<0.01). There is no significant change in the scores for the anxiety and apathy items on the NPI-R scale.
TAP participates in the positive engagement of the elderly people in the interaction with the animal. These results are consistent with the conclusions of the studies on animal mediation and confirm the clinical observations collected. TAP could work by improving self-esteem and valuing all of the person's preserved abilities.
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.
Water deficit and increasing salinization reduce productivity of wheat, the leading crop for human diet. While the complete genome sequence of this crop has not been deciphered, a BAC library ...screening allowed the isolation of TdERF1, the first ethylene response factor gene from durum wheat. This gene is putatively involved in mediating salt stress tolerance and its characterization provides clues toward understanding the mechanisms underlying the adaptation/tolerance of durum wheat to suboptimal growth conditions. TdERF1 expression is differentially induced by high salt treatment in 2 durum wheat varieties, the salt-tolerant Grecale (GR) and the salt-sensitive Om Rabiaa (OR). To further extend these findings, we show here that the expression of this ERF is correlated with physiological parameters, such as the accumulation of osmo-regulators and membrane integrity, that discriminate between the 2 contrasted wheat genotypes. The data confirm that GR and OR are 2 contrasted wheat genotypes with regard to salt-stress and show that TdERF1 is also induced by water stress with an expression pattern clearly discriminating between the 2 genotypes. These findings suggest that TdERF1 might be involved in responses to salt and water stress providing a potential genetic marker discriminating between tolerant and sensitive wheat varieties.
Introduction. Little is known about the impact of organic manure on andosol. Materials and methods. Two varieties of Solanum lycopersicum L. (cvs. ‘Rio grande’ and ‘Rossol VFN’) were grown under ...tropical andosol. The soil was silty, acidic and very poor in Bray P (3 mg·kg–1) with a strong imbalance in the (Ca:Mg:K) ratio of (74.0:25.0:0.7). Five fertilization treatments were used: (i) control with no fertilizer, (ii) minerals, with a (Ca:Mg:K) ratio of (76:18:6) and 75 mg P·kg–1 of soil; (iii) poultry manure with a (Ca:Mg:K) ratio of (68:24:7) and 450 mg P·kg–1 of soil; (iv) a combination of (ii) and (iii), and (v) mineral fertilization as applied by local farmers, with a (Ca:Mg:K) ratio of (73:25:1) and 54 mg P·kg–1 of soil. Results. All cation-balanced treatments (organic, mineral or a combination of both) significantly improved plant growth, the number of trusses and fruits per plant, the marketable fruit yield and fruit P, K, Ca and Na contents of both tomato varieties considered. The ‘Rio grande’ variety was the most productive (32–44 t·ha–1) compared with the ‘Rossol’ variety (20–22 t·ha–1). There was no major difference between the organic fertilizer and the cation-balanced mineral fertilizer. There was no effect of mineral fertilizer with an unbalanced cation composition on tomato plant growth and production as compared with unfertilized control. Conclusion. In tropical andosol poor in potassium and phosphorous and with excess of Mg, application of poultry manure in adequate dosage and at the right time is capable of sustaining tomato fruit production, as well as the application of calculated inorganic fertilizer.
Introduction. Il existe peu d’informations sur l'impact des engrais organiques sur les andosols. Matériel et méthodes. Deux variétés de tomate (Solanum lycopersicum L.), cv. ‘Rio grande’ et ‘Rossol VFN’, ont été cultivées sur andosols tropicaux. Le sol était limoneux, acide, très pauvre en phosphore Bray (3 mg·kg–1 de sol) avec un fort déséquilibre du rapport (Ca:Mg:K) égal à (74.0:25.0:0.7). Cinq traitements de fertilisation ont été testés : (i) traitement témoin sans engrais, (ii) engrais minéral équilibré en cations (rapport (Ca:Mg:K) = (76:18:6) et 75 mg P·kg–1 de sol ; (iii) fumier de volaille avec un rapport (Ca:Mg:K) de (68:24:7) et 450 mg P·kg–1 de sol ; (iv) combinaison des traitements (ii) et (iii) ; (v) fertilisation minérale déséquilibrée en cations, telle qu’appliquée par les agriculteurs locaux rapport (Ca:Mg:K) = (73:25:1) et 54 mg P·kg–1 de sol. Résultats. Les fertilisations équilibrées en cations (organique, minérale ou organo-minérale) ont sensiblement amélioré la croissance des plantes, le nombre de grappes et de fruits par plante, le rendement en fruits commercialisables et la teneur en P, K, Ca et Na des deux variétés de tomate considérées. La variété ‘Rio Grande’ a été plus productive (32–44 t·ha–1) que la variété ‘Rossol’ (20–22 t·ha–1). Il n'y a pas eu de différences majeures entre les plants fertilisés avec l'engrais organique et ceux ayant reçu un engrais minéral équilibré en cations. La fertilisation minérale déséquilibrée en cations n’a pas eu d’effet sur la croissance et la production des plants de tomate par rapport au traitement témoin sans engrais. Conclusion. Dans les andosols tropicaux pauvres en potassium et en phosphore et présentant un excès de magnésium, l'application de fumier de volaille à des doses adaptées et au bon moment permet de maintenir une production de tomates équivalente à celle obtenue avec un engrais minéral bien dosé.
A gene encoding an elongation factor LeEF-Ts
mt 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-Ts
mt
expression is stimulated by ethylene, wounding and high temperature but ethylene-insensitive mutants exhibit normal expression. Transgenic fruit have been generated in which
LeEF-Ts
mt
has been constitutively up- and down-regulated. Surprisingly, altering the expression of the gene by genetic transformation with antisense and sense
LeEF-Ts
mt
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-Ts
mt
gene expression are discussed.
PDF
