Selection for Robustness in Mutagenized RNA Viruses

Mutational robustness is defined as the constancy of a phenotype in the face of deleterious mutations. Whether robustness can be directly favored by natural selection remains controversial. Theory and in silico experiments predict that, at high mutation rates, slow-replicating genotypes can potentially outcompete faster counterparts if they benefit from a higher robustness. Here, we experimentally validate this hypothesis, dubbed the “survival of the flattest,” using two populations of the vesicular stomatitis RNA virus. Characterization of fitness distributions and genetic variability indicated that one population showed a higher replication rate, whereas the other was more robust to mutation. The faster replicator outgrew its robust counterpart in standard competition assays, but the outcome was reversed in the presence of chemical mutagens. These results show that selection can directly favor mutational robustness and reveal a novel viral resistance mechanism against treatment by lethal mutagenesis

Epigenética en técnicas de reproducción asistida: razones y evidencias para una reflexión

Los procesos epigenéticos producen cambios covalentes en la cadena de ADN sin alteración en la secuencia de bases nitrogenadas. Una de las modificaciones epigenéticas más relevantes es el proceso de metilación de citosina. Este proceso es de vital importancia para mantener el silenciamiento génico en el desarrollo normal, la impronta genómica y la inactivación del cromosoma X. Así, por ejemplo, cuando se producen alteraciones en la impronta, estos pueden desencadenar enfermedades, especialmente aquellas relacionadas con defectos en el desarrollo embrionario y el proceso neoplásico. En los últimos años se ha visto que mediante el uso de técnicas de reproducción asistida (TRAs), se pueden ver aumentados los desórdenes de este tipo, motivación suficiente por la que creemos que resulta de interés un mayor conocimiento de las modificaciones epigenéticas y su relación con numerosas enfermedades y disfunciones tras el uso de TRAs, con notables consecuencias sobre el manejo, tratamiento y prevención en el futuro de enfermedades en recién nacidos. En este trabajo, se describen los mecanismos de las modificaciones epigenéticas, más concretamente la metilación de citosina, las implicaciones que tiene dicha metilación de ADN sobre disfunciones y desarrollo de enfermedades en recién nacidos, los factores implicados en TRAs causantes y/o transmisión de la metilación de ADN y, finalmente, las metodologías analíticas para la determinación del grado de metilación en ADN.Epigenetic events lead to covalent modifications at the DNA chain without mutagenic alterations in the DNA sequence. One of the most relevant epigenetic modifications corresponds to the methylation process of cytosine. The above process is of outstanding importance to keep the gene silencing of normal development, genomic imprinting and inactivation of chromosome X. Thus, for instance, when the genomic imprinting suffers alterations, it can trigger the appearance of diseases, mainly those related to defects during the embrionary development or in neoplasic processes. Over the last few years, it has been observed that via the use of assisted reproductive techniques (ARTs) a number of the above disorders and dysfunctions can be proliferated, reason enough for which we strongly demand a more profound knowledge about the epigenetic modifications and their relationships with a wide number of diseases and dysfunctions after ARTs, with notable consequences in the management, treatment and prevention of diseases in newborn babies In this work, the authors describe the mechanisms involved in epigenetic modifications -more particularly cytosine methylation-, the implications of cytosine methylation at DNA upon dysfunctions and development of diseases in newborn babies, causal factors implicated in ARTs and/or transmission of DNA methylation and, finally, the analytical methodologies used for the determination of methylation grade in DNA

Percepción de actos de intimidación hacia adolescentes embarazadas en colegios de Bogotá, Colombia

El embarazo en adolescentes continúa siendo uno de los grandes problemas  de Salud Pública en Colombia y en el mundo. A pesar del mayor reconocimiento de las medidas preventivas, educación en salud sexual y reproductiva y  fácil acceso a los anticonceptivos, se mantienen cifras significativas  de gestantes adolescentes,  por múltiples factores que son agravados por la pérdida de valores, violación a los derechos humanos, características culturales y las malas condiciones socioeconómicas. En este estudio pretendemos establecer la percepción de algunos actos de intimidación que rodean a las adolescentes embarazadas en colegios de educación media de Bogotá en el 2010. Se realizó un estudio de alcance descriptivo en el que se utilizaron las respuestas de 39.044 adolescentes escolarizados a cinco preguntas que indagaban sobre actos de intimidación  en la Encuesta sobre el Comportamiento Sexual de Adolescentes Escolarizados en Bogotá (ECSAE), efectuada en Bogotá durante el primer semestre de 2010. Del total de registros, el 45,4% (17.737) pertenecían a  adolescentes hombres. El 23% de la muestra eran estudiantes de  colegios matriculados en los cursos 9 a 11 de 273 colegios de  Bogotá. El 0,69% de la muestra (272 niñas) estaban  embarazadas  en el momento de realizar la encuesta, de ese grupo, el 10,3% estudiaban  en colegios privados. El acto de intimidación más percibido por  los grupos analizados (22%-71% en colegios privados y 54%-50%  en públicos) fue: los profesores dicen en público que las niñas  cometieron un gran error al quedar embarazadas. Los ambientes escolares deben ser un espacio seguro donde se ofrezca protección a la adolescente embarazada. En este estudio establecimos que las adolescentes embarazadas  son objeto de actos de intimidación por parte de sus compañeros y profesores

Percepción de actos de intimidación hacia adolescentes embarazadas en colegios de Bogotá, Colombia

El embarazo en adolescentes continúa siendo uno de los grandes problemas  de Salud Pública en Colombia y en el mundo. A pesar del mayor reconocimiento de las medidas preventivas, educación en salud sexual y reproductiva y  fácil acceso a los anticonceptivos, se mantienen cifras significativas  de gestantes adolescentes,  por múltiples factores que son agravados por la pérdida de valores, violación a los derechos humanos, características culturales y las malas condiciones socioeconómicas. En este estudio pretendemos establecer la percepción de algunos actos de intimidación que rodean a las adolescentes embarazadas en colegios de educación media de Bogotá en el 2010. Se realizó un estudio de alcance descriptivo en el que se utilizaron las respuestas de 39.044 adolescentes escolarizados a cinco preguntas que indagaban sobre actos de intimidación  en la Encuesta sobre el Comportamiento Sexual de Adolescentes Escolarizados en Bogotá (ECSAE), efectuada en Bogotá durante el primer semestre de 2010. Del total de registros, el 45,4% (17.737) pertenecían a  adolescentes hombres. El 23% de la muestra eran estudiantes de  colegios matriculados en los cursos 9 a 11 de 273 colegios de  Bogotá. El 0,69% de la muestra (272 niñas) estaban  embarazadas  en el momento de realizar la encuesta, de ese grupo, el 10,3% estudiaban  en colegios privados. El acto de intimidación más percibido por  los grupos analizados (22%-71% en colegios privados y 54%-50%  en públicos) fue: los profesores dicen en público que las niñas  cometieron un gran error al quedar embarazadas. Los ambientes escolares deben ser un espacio seguro donde se ofrezca protección a la adolescente embarazada. En este estudio establecimos que las adolescentes embarazadas  son objeto de actos de intimidación por parte de sus compañeros y profesores

FluoroType MTB system for the detection of pulmonary tuberculosis

Altres ajuts: The authors would like to acknowledge Hain Lifescience (Germany) for their provision of a FluoroCycler and sufficient FluoroType MTB assays to carry out the study. Hain Lifescience had no influence on the study design, data analysis or preparation of the manuscript. Funding information for this article has been deposited with the Crossref Funder RegistryDiagnosis continues to be a major barrier for the control of tuberculosis (TB), especially in low- and middle-income countries (LMIC) [1]. The number of platforms for the molecular diagnosis of TB have increased in recent years and they can provide test results more rapidly than culture. Molecular assays are increasingly being used as alternative or adjunct methods to culture and smear microscopy, and modern systems seek to partially or fully automate the DNA extraction and amplification steps, increasing their suitability for resource-limited laboratories. One of these platforms, the GeneXpert MTB/RIF (Cepheid, USA), has a sensitivity of roughly 85% compared to culture [2] and has seen significant uptake in developing countries [3]. However, as a fully closed system, the DNA extracted during the process cannot be used for further downstream drug susceptibility testing (DST), which is crucial for patients with suspected drug-resistant TB. FluoroType MTB is a sensitive test for TB but specificity is low compared with fully integrated molecular system

PRX2 and PRX25, peroxidases regulated by COG1, are involved in seed longevity in Arabidopsis

[EN] Permeability is a crucial trait that affects seed longevity and is regulated by different polymers including proanthocyanidins, suberin, cutin and lignin located in the seed coat. By testing mutants in suberin transport and biosynthesis, we demonstrate the importance of this biopolymer to cope with seed deterioration. Transcriptomic analysis of cog1-2D, a gain-of-function mutant with increased seed longevity, revealed the upregulation of several peroxidase genes. Reverse genetics analysing seed longevity uncovered redundancy within the seed coat peroxidase gene family; however, after controlled deterioration treatment, seeds from the prx2 prx25 double and prx2 prx25 prx71 triple mutant plants presented lower germination than wild-type plants. Transmission electron microscopy analysis of the seed coat of these mutants showed a thinner palisade layer, but no changes were observed in proanthocyanidin accumulation or in the cuticle layer. Spectrophotometric quantification of acetyl bromide-soluble lignin components indicated changes in the amount of total polyphenolics derived from suberin and/or lignin in the mutant seeds. Finally, the increased seed coat permeability to tetrazolium salts observed in the prx2 prx25 and prx2 prx25 prx71 mutant lines suggested that the lower permeability of the seed coats caused by altered polyphenolics is likely to be the main reason explaining their reduced seed longevityRenard, J.; Martínez-Almonacid, I.; Sonntag, A.; Molina, I.; Moya-Cuevas, J.; Bissoli, G.; Muñoz-Bertomeu, J.... (2020). PRX2 and PRX25, peroxidases regulated by COG1, are involved in seed longevity in Arabidopsis. Plant Cell & Environment. 43(2):315-326. https://doi.org/10.1111/pce.13656S315326432Almagro, L., Gómez Ros, L. V., Belchi-Navarro, S., Bru, R., Ros Barceló, A., & Pedreño, M. A. (2008). Class III peroxidases in plant defence reactions. 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A., Summerhurst, D. K., & Razem, F. A. (2004). Oxidases, peroxidases and hydrogen peroxide: The suberin connection. Phytochemistry Reviews, 3(1-2), 113-126. doi:10.1023/b:phyt.0000047810.10706.46Bolger, A. M., Lohse, M., & Usadel, B. (2014). Trimmomatic: a flexible trimmer for Illumina sequence data. Bioinformatics, 30(15), 2114-2120. doi:10.1093/bioinformatics/btu170Bueso, E., Muñoz-Bertomeu, J., Campos, F., Brunaud, V., Martínez, L., Sayas, E., … Serrano, R. (2013). ARABIDOPSIS THALIANA HOMEOBOX25 Uncovers a Role for Gibberellins in Seed Longevity. Plant Physiology, 164(2), 999-1010. doi:10.1104/pp.113.232223Châtelain, E., Satour, P., Laugier, E., Ly Vu, B., Payet, N., Rey, P., & Montrichard, F. (2013). Evidence for participation of the methionine sulfoxide reductase repair system in plant seed longevity. Proceedings of the National Academy of Sciences, 110(9), 3633-3638. doi:10.1073/pnas.1220589110Clerkx, E. J. M., Blankestijn-De Vries, H., Ruys, G. J., Groot, S. P. C., & Koornneef, M. (2004). Genetic differences in seed longevity of various Arabidopsis mutants. Physiologia Plantarum, 121(3), 448-461. doi:10.1111/j.0031-9317.2004.00339.xCosio, C., & Dunand, C. (2009). Specific functions of individual class III peroxidase genes. Journal of Experimental Botany, 60(2), 391-408. doi:10.1093/jxb/ern318Czechowski, T., Stitt, M., Altmann, T., Udvardi, M. K., & Scheible, W.-R. (2005). Genome-Wide Identification and Testing of Superior Reference Genes for Transcript Normalization in Arabidopsis. Plant Physiology, 139(1), 5-17. doi:10.1104/pp.105.063743Debeaujon, I., Léon-Kloosterziel, K. M., & Koornneef, M. (2000). Influence of the Testa on Seed Dormancy, Germination, and Longevity in Arabidopsis. Plant Physiology, 122(2), 403-414. doi:10.1104/pp.122.2.403Duroux, L., & Welinder, K. G. (2003). The Peroxidase Gene Family in Plants: A Phylogenetic Overview. Journal of Molecular Evolution, 57(4), 397-407. doi:10.1007/s00239-003-2489-3Fedi, F., O’Neill, C. M., Menard, G., Trick, M., Dechirico, S., Corbineau, F., … Penfield, S. (2017). Awake1, an ABC-Type Transporter, Reveals an Essential Role for Suberin in the Control of Seed Dormancy. Plant Physiology, 174(1), 276-283. doi:10.1104/pp.16.01556Francoz, E., Ranocha, P., Nguyen-Kim, H., Jamet, E., Burlat, V., & Dunand, C. (2015). Roles of cell wall peroxidases in plant development. Phytochemistry, 112, 15-21. doi:10.1016/j.phytochem.2014.07.020Franke, R., Briesen, I., Wojciechowski, T., Faust, A., Yephremov, A., Nawrath, C., & Schreiber, L. (2005). Apoplastic polyesters in Arabidopsis surface tissues – A typical suberin and a particular cutin. Phytochemistry, 66(22), 2643-2658. doi:10.1016/j.phytochem.2005.09.027Franke, R., & Schreiber, L. (2007). Suberin — a biopolyester forming apoplastic plant interfaces. Current Opinion in Plant Biology, 10(3), 252-259. doi:10.1016/j.pbi.2007.04.004GoffL TrapnellC&KelleyD(2014)CummeRbund: Analysis exploration manipulation and visualization of Cufflinks high‐throughput sequencing data. R package version 2.22.0.Gou, M., Hou, G., Yang, H., Zhang, X., Cai, Y., Kai, G., & Liu, C.-J. (2016). The MYB107 Transcription Factor Positively Regulates Suberin Biosynthesis. Plant Physiology, 173(2), 1045-1058. doi:10.1104/pp.16.01614Graça, J. (2015). Suberin: the biopolyester at the frontier of plants. Frontiers in Chemistry, 3. doi:10.3389/fchem.2015.00062Haughn, G., & Chaudhury, A. (2005). Genetic analysis of seed coat development in Arabidopsis. Trends in Plant Science, 10(10), 472-477. doi:10.1016/j.tplants.2005.08.005Herrero, J., Fernández-Pérez, F., Yebra, T., Novo-Uzal, E., Pomar, F., Pedreño, M. Á., … Zapata, J. M. (2013). Bioinformatic and functional characterization of the basic peroxidase 72 from Arabidopsis thaliana involved in lignin biosynthesis. Planta, 237(6), 1599-1612. doi:10.1007/s00425-013-1865-5Kim, D., Langmead, B., & Salzberg, S. L. (2015). HISAT: a fast spliced aligner with low memory requirements. Nature Methods, 12(4), 357-360. doi:10.1038/nmeth.3317Kosma, D. K., Murmu, J., Razeq, F. M., Santos, P., Bourgault, R., Molina, I., & Rowland, O. (2014). At MYB 41 activates ectopic suberin synthesis and assembly in multiple plant species and cell types. The Plant Journal, 80(2), 216-229. doi:10.1111/tpj.12624Kunieda, T., Shimada, T., Kondo, M., Nishimura, M., Nishitani, K., & Hara-Nishimura, I. (2013). Spatiotemporal Secretion of PEROXIDASE36 Is Required for Seed Coat Mucilage Extrusion in Arabidopsis  . The Plant Cell, 25(4), 1355-1367. doi:10.1105/tpc.113.110072Lee, Y., Rubio, M. C., Alassimone, J., & Geldner, N. (2013). A Mechanism for Localized Lignin Deposition in the Endodermis. Cell, 153(2), 402-412. doi:10.1016/j.cell.2013.02.045Liang, M., Davis, E., Gardner, D., Cai, X., & Wu, Y. (2006). Involvement of AtLAC15 in lignin synthesis in seeds and in root elongation of Arabidopsis. Planta, 224(5), 1185-1196. doi:10.1007/s00425-006-0300-6Li-Beisson, Y., Shorrosh, B., Beisson, F., Andersson, M. X., Arondel, V., Bates, P. D., … Ohlrogge, J. (2013). Acyl-Lipid Metabolism. The Arabidopsis Book, 11, e0161. doi:10.1199/tab.0161Mandel, T., Candela, H., Landau, U., Asis, L., Zilinger, E., Carles, C. C., & Williams, L. E. (2016). Differential regulation of meristem size, morphology and organization by the ERECTA, CLAVATA and class III HD-ZIP pathways. Development. doi:10.1242/dev.129973Milne, I., Stephen, G., Bayer, M., Cock, P. J. A., Pritchard, L., Cardle, L., … Marshall, D. (2012). Using Tablet for visual exploration of second-generation sequencing data. Briefings in Bioinformatics, 14(2), 193-202. doi:10.1093/bib/bbs012Molina, I., Bonaventure, G., Ohlrogge, J., & Pollard, M. (2006). The lipid polyester composition of Arabidopsis thaliana and Brassica napus seeds. Phytochemistry, 67(23), 2597-2610. doi:10.1016/j.phytochem.2006.09.011Molina, I., Ohlrogge, J. B., & Pollard, M. (2007). Deposition and localization of lipid polyester in developing seeds of Brassica napus and Arabidopsis thaliana. The Plant Journal, 53(3), 437-449. doi:10.1111/j.1365-313x.2007.03348.xMoreira‐Vilar F C. Siqueira‐Soares R deC Finger‐Teixeira A. Oliveira de D. M. Ferro AP Rocha daG J. Ferrarese M deLL Santos dosW. D. Ferrarese‐Filho O(2014).The Acetyl Bromide Method Is Faster Simpler and Presents Best Recovery of Lignin in Different Herbaceous Tissues than Klason and Thioglycolic Acid Methods. PLoS ONE 9:e110000.https://doi.org/10.1371/journal.pone.0110000Oñate-Sánchez, L., & Vicente-Carbajosa, J. (2008). DNA-free RNA isolation protocols for Arabidopsis thaliana, including seeds and siliques. BMC Research Notes, 1(1), 93. doi:10.1186/1756-0500-1-93Østergaard, L., Teilum, K., Mirza, O., Mattsson, O., Petersen, M., Welinder, K. G., … Henriksen, A. (2000). Plant Molecular Biology, 44(2), 231-243. doi:10.1023/a:1006442618860Pfaffl, M. W. (2001). A new mathematical model for relative quantification in real-time RT-PCR. Nucleic Acids Research, 29(9), 45e-45. doi:10.1093/nar/29.9.e45Passardi, F., Longet, D., Penel, C., & Dunand, C. (2004). The class III peroxidase multigenic family in rice and its evolution in land plants☆☆☆. Phytochemistry, 65(13), 1879-1893. doi:10.1016/j.phytochem.2004.06.023Pedreira, J., Herrera, M. T., Zarra, I., & Revilla, G. (2010). The overexpression of AtPrx37, an apoplastic peroxidase, reduces growth in Arabidopsis. Physiologia Plantarum, 141(2), 177-187. doi:10.1111/j.1399-3054.2010.01427.xPollard, M., Beisson, F., Li, Y., & Ohlrogge, J. B. (2008). Building lipid barriers: biosynthesis of cutin and suberin. Trends in Plant Science, 13(5), 236-246. doi:10.1016/j.tplants.2008.03.003Quiroga, M., Guerrero, C., Botella, M. A., Barceló, A., Amaya, I., Medina, M. I., … Valpuesta, V. (2000). A Tomato Peroxidase Involved in the Synthesis of Lignin and Suberin. Plant Physiology, 122(4), 1119-1128. doi:10.1104/pp.122.4.1119Rains, M. K., Gardiyehewa de Silva, N. D., & Molina, I. (2017). Reconstructing the suberin pathway in poplar by chemical and transcriptomic analysis of bark tissues. Tree Physiology, 38(3), 340-361. doi:10.1093/treephys/tpx060Russell, W. R., Burkitt, M. J., Scobbie, L., & Chesson, A. (2005). EPR Investigation into the Effects of Substrate Structure on Peroxidase-Catalyzed Phenylpropanoid Oxidation. Biomacromolecules, 7(1), 268-273. doi:10.1021/bm050636oSano, N., Rajjou, L., North, H. M., Debeaujon, I., Marion-Poll, A., & Seo, M. (2015). Staying Alive: Molecular Aspects of Seed Longevity. Plant and Cell Physiology, 57(4), 660-674. doi:10.1093/pcp/pcv186Shigeto, J., Itoh, Y., Hirao, S., Ohira, K., Fujita, K., & Tsutsumi, Y. (2015). Simultaneously disrupting AtPrx2 , AtPrx25 and AtPrx71 alters lignin content and structure in Arabidopsis stem. Journal of Integrative Plant Biology, 57(4), 349-356. doi:10.1111/jipb.12334Shigeto, J., Kiyonaga, Y., Fujita, K., Kondo, R., & Tsutsumi, Y. (2013). Putative Cationic Cell-Wall-Bound Peroxidase Homologues in Arabidopsis, AtPrx2, AtPrx25, and AtPrx71, Are Involved in Lignification. Journal of Agricultural and Food Chemistry, 61(16), 3781-3788. doi:10.1021/jf400426gSoliday, C. L., Dean, B. B., & Kolattukudy, P. E. (1978). Suberization: Inhibition by Washing and Stimulation by Abscisic Acid in Potato Disks and Tissue Culture. Plant Physiology, 61(2), 170-174. doi:10.1104/pp.61.2.170Tobimatsu, Y., Chen, F., Nakashima, J., Escamilla-Trevino, L. L., Jackson, L., Dixon, R. A., & Ralph, J. (2013). Coexistence but Independent Biosynthesis of Catechyl and Guaiacyl/Syringyl Lignin Polymers in Seed Coats. The Plant Cell, 25(7), 2587-2600. doi:10.1105/tpc.113.113142Trapnell, C., Hendrickson, D. G., Sauvageau, M., Goff, L., Rinn, J. L., & Pachter, L. (2012). 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Peripheral membrane TTL proteins safeguard cellulose synthesis under stress.

Land plants provide around eighty percent of biomass on Earth and roughly one-third corresponds to cellulose (Bar-On et al 2018). Despite its biological and societal importance, many aspects of cellulose biosynthesis and regulation remain elusive. Controlled primary cell wall remodeling allows plant growth under stressful conditions, but how these changes are conveyed to adjust cellulose synthesis is not well understood (Colin et al 2023). In this work, we identify that Tetratricopeptide Thioredoxin-Like (TTL) proteins, which we previous describe as a scaffold of brassinosteroids signalling components, are also new members of the cellulose synthase complex (CSC) and we describe their unique and hitherto unknown dynamic association with the CSC under cellulose-deficient conditions (Amorim-Silva et al 2019 and Kesten, García-Moreno, Amorim-Silva et al 2022). We found out that TTLs are essential for maintaining cellulose synthesis under high salinity conditions, establishing a stress-resilient cortical microtubule array, and stabilizing CSCs at the plasma membrane. To fulfill these functions, TTLs interact with Cellulose Synthase1 (CESA1) and engage with cortical microtubules to promote their polymerization. We propose that TTLs function as bridges connecting stress perception with dynamic regulation of cellulose biosynthesis at the plasma membrane. In addition, we are currently working to identify and characterize new components involved in TTLs function and dynamics during cellulose biosynthesis under saline stress conditions. References: Amorim-Silva et al. 2019 The Plant Cell Bar-On et al. 2018 Proc. Natl. Acad. Sci. Colin et al. 2023 The Plant Cell Kesten, García-Moreno, Amorim-Silva et al. 2022 Sci. Adv.Meeting attendance was supported by Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. This work was funded by the Spanish Ministry for Science and Innovation (MCIN/AEI/ 10.13039/501100011033) (PGC2018-098789-B-I00) and (PID2019-107657RB-C22) to MAB, NRL and AC respectively. The Andalusian Research Plan co-financed by the European Union (PAIDI 2020-PY20_00084) to MAB andde Andalucía UMA-FEDER project (grant UMA18-FEDERJA-154) to NRL, and the Swiss National foundation to CSR (SNF 31003A_163065/1 to AM). CK was supported by a Peter und Traudl Engelhorn-Stiftung fellowship, an ETH Career Seed Grant (SEED-05 19-2) of the ETH Foundation, an Emerging Investigator grant (NNF20OC0060564) of the Novo Nordisk Foundation, and an Experiment grant (R346-2020-1546) of the Lundbeck foundation. AGM and FP were supported by BES-2015-071256 and FPU19/02219 fellowships respectively. VAS was supported by an Emerging Investigator research project (UMA20-FEDERJA-007) and co-financed by the “Programa Operativo FEDER 2014-2020” and by the “Consejería de Economía y Conocimiento de la Junta de Andalucía”.

Acute phase proteins and IP-10 in plasma for tuberculosis diagnosis

Background: Tuberculosis (TB) is a leading cause of death from a single infectious agent, and triage tests based on biomarkers may help to improve the diagnosis. This study aims to determine whether C-reactive protein (CRP), interferon-γ-inducible protein 10 (IP-10), α1-acid glycoprotein (AGP), and α1-anti-trypsin (AAT) could be useful for a screening test in patients with presumptive TB disease. Methods: CRP, IP-10, AGP, and AAT were measured in plasma samples from 277 patients with presumptive TB disease in the Republic of Moldova in a prospective study. Results: In general, the levels of all the biomarkers were higher in patients with TB than in the other groups (p < 0.05). Receiver operating characteristic curve analyses showed an area under the curve lower than 0.7 for all the biomarkers, and low correlations (Spearman's r < 0.6) were found between biomarkers. Conclusion: The levels of the tested biomarkers were different throughout the patient groups studied, but their suboptimal diagnostic performance either as individual biomarkers or in combination does not favor their use for triage testing

Endogenous indole-3-acetamide levels contribute to the crosstalk between auxin and abscisic acid, and trigger plant stress responses in Arabidopsis

Centro de Biotecnología y Genómica de Plantas (CBGP)The evolutionary success of plants relies to a large extent on their extraordinary ability to adapt to changes in their environment. These adaptations require that plants balance their growth with their stress responses. Plant hormones are crucial mediators orchestrating the underlying adaptive processes. However, whether and how the growth-related hormone auxin and the stress-related hormones jasmonic acid, salicylic acid, and abscisic acid (ABA) are coordinated remains largely elusive. Here, we analyse the physiological role of AMIDASE 1 (AMI1) in Arabidopsis plant growth and its possible connection to plant adaptations to abiotic stresses. AMI1 contributes to cellular auxin homeostasis by catalysing the conversion of indole-acetamide into the major plant auxin indole-3-acetic acid. Functional impairment of AMI1 increases the plant's stress status rendering mutant plants more susceptible to abiotic stresses. Transcriptomic analysis of ami1 mutants disclosed the reprogramming of a considerable number of stress-related genes, including jasmonic acid and ABA biosynthesis genes. The ami1 mutants exhibit only moderately repressed growth but an enhanced ABA accumulation, which suggests a role for AMI1 in the crosstalk between auxin and ABA. Altogether, our results suggest that AMI1 is involved in coordinating the trade-off between plant growth and stress responses, balancing auxin and ABA homeostasis.This research was supported by grants from the German Research Foundation (DFG, SFB480/A10) and the Spanish Ministry of Economy, Industry and Competitiveness (MINECO, BFU2017-82826-R to SP and a grant from the Swedish Research Council (VR) to HA. JM was supported by the ‘Severo Ochoa Program for Centers of Excellence in R&D’ from the Agencia Estatal de Investigación of Spain, grant SEV-2016-0672 (2017-2021) to the CBGP.Peer reviewed17 Pág