Plant Transcriptome Reprograming and Bacterial Extracellular Metabolites Underlying Tomato Drought Resistance Triggered by a Beneficial Soil Bacteria

Water deficit is one of the major constraints to crop production and food security worldwide. Some plant growth-promoting rhizobacteria (PGPR) strains are capable of increasing plant drought resistance. Knowledge about the mechanisms underlying bacteria-induced plant drought resistance is important for PGPR applications in agriculture. In this study, we show the drought stress-mitigating effects on tomato plants by the Bacillus megaterium strain TG1-E1, followed by the profiling of plant transcriptomic responses to TG1-E1 and the profiling of bacterial extracellular metabolites. Comparison between the transcriptomes of drought-stressed plants with and without TG1-E1 inoculation revealed bacteria-induced transcriptome reprograming, with highlights on differentially expressed genes belonging to the functional categories including transcription factors, signal transduction, and cell wall biogenesis and organization. Mass spectrometry-based analysis identified over 40 bacterial extracellular metabolites, including several important regulators or osmoprotectant precursors for increasing plant drought resistance. These results demonstrate the importance of plant transcriptional regulation and bacterial metabolites in PGPR-induced plant drought resistance.Chinese Academy of Science

The funerary monuments in the Roman Hispania and their epigraphy in the National Museum of Roman Art of Merida. A didactic proposal addressed to students of Classical Culture and Latin in ESO and Bachillerato

El mundo funerario en la Hispania romana presenta una gran variedad en sus tipos monumentales. Del estudio de los monumentos y la tipología funeraria se extrae información no sólo cultural y religiosa, sino también referente a aspectos sociológicos, demográficos, epigráficos, artísticos e iconográficos. La antigua capital de la Lusitania romana, Augusta Emerita, albergaba en su solar una nutrida, variada e interesante muestra del mejor arte funerario hispanorromano. Presentamos, por ello, un recorrido por una selección de piezas del Museo Nacional de Arte Romano de Mérida, acompañado de una propuesta de actividades didácticas, destinado a alumnos de Cultura Clásica y Latín de E.S.O. y del Bachillerato.The funerary world in the Roman Hispania showed a great deal of monumental models. Through the study of its monuments and their typology, not only can we gather religious and cultural information but we can also draw conclusions regarding sociological, demographic, epigraphic, artistic and iconographic features. Emerita Augusta, the old capital of the Roman Lusitania, housed a wide range of the best Hispano-Roman funerary artistic manifestations. That is why we are presenting a tour around several pieces from the Roman Art Museum in Mérida, together with a series of didactic activities addressed to students of Classical Culture and Latin in E. S. O. (Secondary Compulsory Education) and Bachillerato (Non Compulsory Secondary Education).peerReviewe

The Effects of Plant-Associated Bacterial Exopolysaccharides on Plant Abiotic Stress Tolerance

This research was funded by the Spanish Ministry for Economy and Competitiveness and the European Union, within the context of the research project CGL2017-91737-EXP and by the Andalusian Regional Government and the European Union under the aegis of research project P18-RT-976.Plant growth-promoting rhizobacteria (PGPR) are beneficial soil microorganisms that can stimulate plant growth and increase tolerance to biotic and abiotic stresses. Some PGPR are capable of secreting exopolysaccharides (EPS) to protect themselves and, consequently, their plant hosts against environmental fluctuations and other abiotic stresses such as drought, salinity, or heavy metal pollution. This review focuses on the enhancement of plant abiotic stress tolerance by bacterial EPS. We provide a comprehensive summary of the mechanisms through EPS to alleviate plant abiotic stress tolerance, including salinity, drought, temperature, and heavy metal toxicity. Finally, we discuss how these abiotic stresses may affect bacterial EPS production and its role during plant-microbe interactions.Spanish Ministry for Economy and CompetitivenessEuropean Commission P18-RT-976 CGL2017-91737-EXPAndalusian Regional Governmen

The funerary monuments in the Roman Hispania and their epigraphy in the National Museum of Roman Art of Merida. A didactic proposal addressed to students of Classical Culture and Latin in ESO and Bachillerato

El mundo funerario en la Hispania romana presenta una gran variedad en sus tipos monumentales. Del estudio de los monumentos y la tipología funeraria se extrae información no sólo cultural y religiosa, sino también referente a aspectos sociológicos, demográficos, epigráficos, artísticos e iconográficos. La antigua capital de la Lusitania romana, Augusta Emerita, albergaba en su solar una nutrida, variada e interesante muestra del mejor arte funerario hispanorromano. Presentamos, por ello, un recorrido por una selección de piezas del Museo Nacional de Arte Romano de Mérida, acompañado de una propuesta de actividades didácticas, destinado a alumnos de Cultura Clásica y Latín de E.S.O. y del Bachillerato.The funerary world in the Roman Hispania showed a great deal of monumental models. Through the study of its monuments and their typology, not only can we gather religious and cultural information but we can also draw conclusions regarding sociological, demographic, epigraphic, artistic and iconographic features. Emerita Augusta, the old capital of the Roman Lusitania, housed a wide range of the best Hispano-Roman funerary artistic manifestations. That is why we are presenting a tour around several pieces from the Roman Art Museum in Mérida, together with a series of didactic activities addressed to students of Classical Culture and Latin in E. S. O. (Secondary Compulsory Education) and Bachillerato (Non Compulsory Secondary Education).peerReviewe

Efecto de distintos oxidantes sobre la calidad de panes elaborados por el método tradicional argentino

La metodología de panificación tradicional argentina se destaca por utilizar escasa levadura y realizar fermentaciones muy largas, utilizando como oxidante bromato de potasio. Con la prohibición del uso de bromato desde el año 1998,cobró importancia el análisis de la acción de distintos oxidantes en estos procesos.En el presente trabajo se estudió la acción de 5 oxidantes sobre la retención de gases, el volumen de pan, las propiedades reológicas, la estructura de la miga y las interacciones entre proteínas. Los resultados de las electroforesis muestran que los oxidantes favorecen la formación de agregados proteicos, lo que estaría indicando el establecimiento de puentes disulfuro a partir de grupos sulfhidrilo. También se observa que ninguno de los aditivos en estudio puede suplantar por sí solo al bromato de potasio en este tipo de panificación, siendo la azodicarbonamida el oxidante que tiene el comportamiento más simila

Cell-free microbial culture filtrates as candidate biostimulants to enhance plant growth and yield and activate soil- and plant-associated beneficial microbiota

In this work we compiled information on current and emerging microbial-based fertilization practices, especially the use of cell-free microbial culture filtrates (CFs), to promote plant growth, yield and stress tolerance, and their effects on plant-associated beneficial microbiota. In addition, we identified limitations to bring microbial CFs to the market as biostimulants. In nature, plants act as metaorganisms, hosting microorganisms that communicate with the plants by exchanging semiochemicals through the phytosphere. Such symbiotic interactions are of high importance not only for plant yield and quality, but also for functioning of the soil microbiota. One environmentally sustainable practice to increasing crop productivity and/or protecting plants from (a)biotic stresses while reducing the excessive and inappropriate application of agrochemicals is based on the use of inoculants of beneficial microorganisms. However, this technology has a number of limitations, including inconsistencies in the field, specific growth requirements and host compatibility. Beneficial microorganisms release diffusible substances that promote plant growth and enhance yield and stress tolerance. Recently, evidence has been provided that this capacity also extends to phytopathogens. Consistently, soil application of microbial cell-free culture filtrates (CFs) has been found to promote growth and enhance the yield of horticultural crops. Recent studies have shown that the response of plants to soil application of microbial CFs is associated with strong proliferation of the resident beneficial soil microbiota. Therefore, the use of microbial CFs to enhance both crop yield and stress tolerance, and to activate beneficial soil microbiota could be a safe, efficient and environmentally friendly approach to minimize shortfalls related to the technology of microbial inoculation. In this review, we compile information on microbial CFs and the main constituents (especially volatile compounds) that promote plant growth, yield and stress tolerance, and their effects on plant-associated beneficial microbiota. In addition, we identify challenges and limitations for their use as biostimulants to bring them to the market and we propose remedial actions and give suggestions for future work.This work was supported by the Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (Spain) (grant PID2019-104685GB-100)

Histogenesis and cell differentiation in the retina of Thunnus thynnus: a morphological and immunohistochemical study

This study examines the anatomical development of the visual system of Atlantic bluefin tuna, Thunnus thynnus, during the first 15 days of life at histological level, with emphasis in the immunohistochemical characterization of different cell types. As an altricial fish species, the retina was not developed at hatching. The appearance of eye pigmentation and the transformation of the retina from an undifferentiated neuroblastic layer into a laminated structure occurred during the first two days of life. At 16 days after hatching (DAH), the ganglion cells were arranged in a single row in the central region of the retina and the outer segments of the photoreceptors were morphologically developed. Furthermore, at this age, all the retinal cell types were immunohistochemically characterized. The presence of ganglion cell axons was confirmed with the TUJ1 antibody and the existence of functional synapses in the plexiform layers with antibodies against SV2. Cone opsins were immunostained with antibodies against visinin and CERN-922 immunoreactive rods were also identified. Different subpopulations of amacrine cells were immunostained with antibodies against αTH and PV. Highly GS-immunoreactive Müller cells were also detected at this age. These observations suggested that the T. thynnus retina was fully functional at the end of the second week of life. Basic studies on early morphology of the visual system and larval behaviour are necessary to support applied research on larval rearing. Furthermore, they may have implications for understanding larval ecology in the wild.Versión del edito

PGI1-mediated vascular pentose phosphate pathway activity determines growth, photosynthesis and metabolism through 2-C-methyl-D-erythritol 4-P pathway action in Arabidopsis

Resumen del trabajo presentado en el XVI Meeting of Plant Molecular Biology, celebrado en Sevilla (España), del 14 al 16 de septiembre de 2022Phosphoglucose isomerase is involved in the early steps of glycolysis and regeneration of glucose-6-phosphate pools in the pentose phosphate pathway (PPP). In Arabidopsis, plastidial phosphoglucose isomerase (PGI1) is an important determinant of growth, metabolism and photosynthesis, probably due to its involvement in the synthesis of 2-C-methyl-D-erythritol 4-P (MEP)-derived hormones in root tips and vascular tissues (Bahaji et al., 2015; Bahaji et al., 2018). To test this hypothesis, we conducted proteomic and metabolic characterization of PGI1-null pgi1-2 plants. We also characterized pgi1-2 plants ectopically expressing PGI1 under the control of a root tip- and vascular tissue-specific promoter. Furthermore, we characterized pfk4/pfk5 knockout plants impaired in the early steps of plastidial glycolysis, and pgl3-1 plants with reduced activity of the plastidial PPP enzyme 6-phosphogluconolactonase 3. The overall data obtained in this work provide strong evidence that root tip and vascular PGI1-mediated plastidial PPP determines growth, development and photosynthesis through MEP pathway action.This work was supported by the Ministerio de Ciencia e Innovación (MCIN) and Agencia Estatal de Investigación (AEI) / 10.13039/501100011033/ (grants BIO2016-78747-P, PID2019-104685GB-100) and the Ministry of Education, Youth and Sport of the Czech Republic and ERDF project entitled “Plants as a tool for sustainable global development” (No. CZ.02.1.01/0.0/0.0/16_019/0000827)

Vascular and root tip GPT2 expression mediates the PGI1-independent response of Arabidopsis to small microbial volatiles

Resumen del trabajo presentado en el XVI Meeting of Plant Molecular Biology, celebrado en Sevilla (España), del 14 al 16 de septiembre de 2022Microorganisms emit a plethora of volatile compounds (VCs) that promote plant growth and photosynthesis as well as strong developmental and metabolic changes. In Arabidopsis, the plastidial isoform of phosphoglucose isomerase PGI1 mediates photosynthesis, metabolism and development, probably due to its involvement in the synthesis of isoprenoid-derived signals in vascular tissues (Bahaji et al., 2015; Bahaji et al., 2018). Like in wild-type (WT) plants, microbial VCs promote growth and photosynthesis as well as starch and CK accumulation in PGI1-lacking pgi1-2 plants (Sánchez-López et al. 2016). A striking alteration in the transcriptome of leaves of small fungal VC-treated plants involves strong up-regulation of levels of transcripts of GPT2 (At1g61800), a gene that codes for a plastidial G6P/Pi transporter. We hypothesized that the PGI1-independent response to microbial volatile emissions involves GPT2 action. To test this hypothesis, we characterized responses of WT, GPT2-null gpt2-1, PGI1-null pgi1-2 and pgi1- 2gpt2-1 plants to small fungal VCs. In addition, we characterized responses of pgi1-2gpt2-1 plants expressing GPT2 under the control of a vascular tissue- and root tip-specific promoter to small fungal VCs. Results presented in this work provide evidence that, under conditions in which PGI1 activity is reduced, long-distance action of GPT2 plays an important role in the response of plants to small VCs through mechanisms involving resetting of the photosynthesis-related proteome in leaves and complex GPT2 regulation.This work was supported by the Ministerio de Ciencia e Innovación (MCIN) and Agencia Estatal de Investigación (AEI) / 10.13039/501100011033/ (grants BIO2016-78747-P, PID2019-104685GB-100 and PID2019-107657RB-C22) and the Ministry of Education, Youth and Sport of the Czech Republic and ERDF project entitled “Plants as a tool for sustainable global development” (No. CZ.02.1.01/0.0/0.0/16_019/0000827)

Epigenetic changes in the metabolically healthy obese: A case-control versus a prospective study

Obesity has become a worldwide health problem, in which latest statistics reported an increased trend over the last years. Accordingly, long-term obesity is involved in an increased risk of developing several metabolic diseases, such as cardiovascular diseases, insulin resistance or type 2 diabetes. Although it is common to find obesity-related disorders in the majority of individuals with obesity, some of them do not show metabolic complications.1 Obese people without these metabolic disorders are defined as metabolically healthy obesity (MHO) individuals, whereas those who present metabolic complications are known as metabolically unhealthy obesity (MUO) subjects.2 Importantly, the prevalence of this healthy phenotype varies widely, in which a correct diagnosis is critical for a good prognosis.2, 3 Nevertheless, the variability of this prevalence may be due to the nature of related-study designs and the studied populations or the confounding variables considered. Therefore, conducting appropriately designed studies to evaluate important clinical research questions is crucial, to elucidate the impact of MHO in the progression of detrimental obesity-related phenotypes.4 In this case, epigenetic arises as a valuable tool for clinical applications. Epigenetic mechanisms might be implicated in the regulation of several metabolic disorders.5 However, until now, only a few studies have been conducted to understand the epigenetic changes in individuals with MHO and MUO.6-8 Therefore, we hypothesized that epigenetic changes may be involved in the development and the transition from MHO to MUO phenotype. Consequently, the aim of this study was to analyze the epigenome-wide DNA methylation study in peripheral blood mononuclear cells (PMBCs) from participants with MHO and MUO, by using two study designs, such as case-control and prospective approaches.TMLP and CGR were supported by a grant from Instituto de Salud Carlos III (FI19/00178 and CP20/00066, respectively). HB is supported by a predoctoral fellowship ("Plan Propio IBIMA 2020 A.1 Contratos predoctorales", Ref.: predoc20_002). SM, MMG and GRM are supported by Nicolas Monardes program from the Consejería de Salud de la Junta de Andalucía (RC-0008-2021, RC-0001-2018 and C-0060-2012, respectively). EAL was recipient of a postdoctoral fellowship from regional Andalusian Government (Ref: 2020_DOC_00541). This work was supported in part by a grant from the Instituto de Salud Carlos III (PI15-01350). This study has been co-funded by FEDER funds (“A way to make Europe”). CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN) and CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM) are ISCIII. Funding for open access charge: Universidad de Málaga / CBU