Genome-Wide Mapping of Histone H3 Lysine 4 Trimethylation (H3K4me3) and Its Involvement in Fatty Acid Biosynthesis in Sunflower Developing Seeds

15 Páginas.-- 5 Figuras.-- 3 TablasHistone modifications are of paramount importance during plant development. Investigating chromatin remodeling in developing oilseeds sheds light on the molecular mechanisms controlling fatty acid metabolism and facilitates the identification of new functional regions in oil crop genomes. The present study characterizes the epigenetic modifications H3K4me3 in relationship with the expression of fatty acid-related genes and transcription factors in developing sunflower seeds. Two master transcriptional regulators identified in this analysis, VIV1 (homologous to Arabidopsis ABI3) and FUS3, cooperate in the regulation of WRINKLED 1, a transcriptional factor regulating glycolysis, and fatty acid synthesis in developing oilseeds.This research was funded by the Spanish AEI/FEDER (UE), Project AGL2017-83449-R.Peer reviewe

Efecto de la variabilidad de las propiedades físico-químicas del suelo en el rendimiento de la halófita costera Crithmum maritimum L.

Póster presentado en el XV Congreso Nacional de la AEET. "El valor de la naturaleza par una sociedad global"18-21 de octubre, Plasencia, CáceresEl hinojo marino (Crithmum maritimum L.) es una planta halófita perenne perteneciente a la familia Apiaceae, típica de ecosistemas costeros de Europa Occidental. Dada su elevada calidad nutricional para consumo humano, en los últimos años diferentes estudios han resaltado su potencial como cultivo comercial para la agricultura salina, una alternativa sostenible y prometedora ante la creciente salinización de las tierras agrícolas. Sin embargo, existe una falta de información referente a los rangos de tolerancia de la especie frente a los principales factores ambientales ligados a su cultivo, a lo que se suman diversas dificultades prácticas ligadas al cultivo de una especie no domesticada. Además, varios estudios han puesto de manifiesto un alto grado de variabilidad en los rangos de tolerancia a la sal, así como en el perfil nutricional en función de la procedencia geográfica del material. En este estudio se analizó el rendimiento de la especie (en términos de crecimiento, productividad, éxito reproductivo y calidad nutricional) en relación a las propiedades físico-químicas del suelo (pH, conductividad eléctrica, textura, contenido en materia orgánica y macro- y micronutrientes) en siete poblaciones naturales, representativas de los diferentes tipos de hábitat de la especie, localizadas en el sur de la Península Ibérica. Los resultados de este estudio permiten avanzar en el conocimiento ecológico y los mecanismos de tolerancia de las halófitas frente a diferentes factores abióticos, como la salinidad y la riqueza nutricional del suelo, aportando asimismo información relevante de cara a la valorización de la especie para su explotación en agricultura salinaN

Differences in nutrient composition of sea fennel (Crithmum maritimum) grown in different habitats and optimally controlled growing conditions

10 páginas.- 1 figura.- 5 tablas.- referenciasCrithmum maritimum L. is an edible halophyte with large potential in human nutrition field. However, it is unclear whether its nutritional value is maintained throughout the contrasting habitats where it commonly grows (cliffs, sandy and rocky beaches) and the nutritional profile of cultivated plants still remains uncertain. In this work, we provided for the first time a comparison of the nutritional profile of C. maritimum across its different type of habitats in the south of Spain and between wild plants and plant material under optimal growing conditions. The protein, amino acids, lipids, fatty acids, minerals composition and phenolic content of plants were analysed. Plants under field conditions exhibited a nutritionally balanced composition (3.8–6.2 g protein/100 g DW, 4.9–7.5 mg lipids/g WW, 3.9–5.0 g Na/100 g DW), with high phenolic content (30.2–48.0 mg/g DW) regardless of the variability of the contrasting habitats. In contrast, under optimal conditions, C. maritimum showed a greater protein and lipid content (10.2 g/100 g DW and 9.6 mg/g WW, respectively), and lower sodium accumulation (1.2 g/100 g DW), allowing a greater consumption of this halophyte without exceeding the daily intake recommendations. Conversely, phenolics were strongly decreased in these plants (6.1 mg/g DW) likely due to the absence of stress factors. © 2021 Elsevier Inc.This work was financially supported by two grants from the Spanish Ministry of Science, Innovation and Universities (RTI2018-099260-A- I00 to J. Cambroll é and RTI2018-099322-B-100 to X. Moreira).Peer reviewe

Characterization of the acyl-ACP thioesterases from Koelreuteria paniculata reveals a new type of FatB thioesterase

© 2020 The Authors.Koelreuteria paniculata is a deciduous tree, popular in temperate regions for its ornamental value, which accumulates unusual cyanolipids in its seeds. The seed oil of this plant is rich in the unusual cis-11-eicosenoic fatty acid (20:1, or gondoic acid), a monounsaturated oil of interest to the oleochemical industry. In higher plants, de novo fatty acid biosynthesis takes place in the plastids, a process that is terminated by hydrolysis of the thioester bond between the acyl moiety and the ACP by acyl-ACP thioesterases. The specificity of acyl-ACP thioesterases is fundamental in controlling the fatty acid composition of seed oil. To determine the mechanisms involved in fatty acid biosynthesis in K. paniculata seeds, we isolated, cloned and sequenced two cDNAs encoding acyl-ACP thioesterases in this plant, KpFatA and KpFatB. Both of them were expressed heterologously in Escherichia coli and characterized with different acyl-ACP substrates. The K. paniculata FatB2 displayed unusual substrate specificity, so that unlike most FatB2 type enzymes, it displayed preference for oleoyl-ACP instead of palmitoyl-ACP. This specificity was consistent with the changes in E. coli and N. benthamiana fatty acid composition following heterologous expression of this enzyme. KpFatB also showed certain genetic divergence relative to other FatB-type thioesterases and when modelled, its structure revealed differences at the active site. Together, these results suggest that this thioesterase could be a new class of FatB not described previously.This work was supported by the AEI (Agencia Estatal de Investigación) and FEDER Project AGL2017-83449-R

Cloning and characterization of two acyl-ACP thioesterases from Koelreuteria paniculate.

17th Euro Fed Lipid Congress 20-23 October 2019, Seville, Spaincis-11-Eicosenoic acid (20:1¿¿9, EA) is a monounsaturated fatty acid that is contained in a variety of plant oils. Some of these oils have a special interest for the industry due to they could be used in engine lubricant oil, pharmaceutical compounds and cosmetics. Approximately 48% of the fatty acid composition in Koelreuteria paniculate oil correspond to EA. The specificity of the acyl-ACP thioesterases plays an important role in controlling the fatty acid composition of seed oil. In order to determine the mechanisms involved in the biosynthesis of fatty acids in Koelreuteria paniculate seeds, we isolated, cloned and sequenced two cDNA coding for acyl-ACP thioesterases, KpFatA1 and KpFatB1. Both of them were heterologously expressed in Escherichia coli and characterized with different acyl-ACP substrates. Whereas KpFatA1 encodes a functional thioesterase with preference for monounsaturated acyl-ACPs (18:1-ACP), the KpFatB1 thioesterase showed higher efficiencies (kcat/KM) for saturated acyl-ACPs (18:0-ACP and 16:0-ACP) than KpFatA1. Lipid composition of tobacco leaves agroinfiltered with KpFatA1 and KpFatB1 for their transient expression was analysed. The results showed changes in the fatty acid composition of leaves overexpressing KpFats respect to non-agroinfiltered ones