Oils and fats on food: is it possible to have a healthy diet?

Oils and fats are an important part of our diet as components of many food formulations. Thus, they are retailed for domestic or hostelry uses and broadly used by food industry for the elaboration of margarines, ice cream, canned food, pre-cooked dishes, bakery, confectionary, chocolates, etc. Chemically, the main component of oils and fats are triacylglycerols (TAGs), which account for up to 95% of their total weight. They consisted of a molecule of glycerol esterified with three fatty acids, usually the saturated, palmitic and stearic, the monounsatu�rated oleic, and the polyunsaturated, linoleic or linolenic, all with 18 carbons excepting the palmitic which has 16 carbons. Out of those most common fatty acids, we can found other fatty acids present only in certain oils such as saturated medium chained fatty acids like lauric and myristic, which contain 12 and 14 carbons respectively

Oils and fats on food: is it possible to have a healthy diet?

Oils and fats are an important part of our diet as components of many food formulations. Thus, they are retailed for domestic or hostelry uses and broadly used by food industry for the elaboration of margarines, ice cream, canned food, pre-cooked dishes, bakery, confectionary, chocolates, etc. Chemically, the main component of oils and fats are triacylglycerols (TAGs), which account for up to 95% of their total weight. They consisted of a molecule of glycerol esterified with three fatty acids, usually the saturated, palmitic and stearic, the monounsatu�rated oleic, and the polyunsaturated, linoleic or linolenic, all with 18 carbons excepting the palmitic which has 16 carbons. Out of those most common fatty acids, we can found other fatty acids present only in certain oils such as saturated medium chained fatty acids like lauric and myristic, which contain 12 and 14 carbons respectively

Chloroplast damage induced by the inhibition of fatty acid synthesis triggers autophagy in chlamydomonas

Fatty acids are synthesized in the stroma of plant and algal chloroplasts by the fatty acid synthase complex. Newly synthesized fatty acids are then used to generate plastidial lipids that are essential for chloroplast structure and function. Here, we show that inhibition of fatty acid synthesis in the model alga Chlamydomonas reinhardtii activates autophagy, a highly conserved catabolic process by which cells degrade intracellular material under adverse conditions to maintain cell homeostasis. Treatment of Chlamydomonas cells with cerulenin, a specific fatty acid synthase inhibitor, stimulated lipidation of the autophagosome protein ATG8 and enhanced autophagic flux. We found that inhibition of fatty acid synthesis decreased monogalactosyldiacylglycerol abundance, increased lutein content, down-regulated photosynthesis, and increased the production of reactive oxygen species. Electron microscopy revealed a high degree of thylakoid membrane stacking in cerulenin-treated cells. Moreover, global transcriptomic analysis of these cells showed an up-regulation of genes encoding chloroplast proteins involved in protein folding and oxidative stress and the induction of major catabolic processes, including autophagy and proteasome pathways. Thus, our results uncovered a link between lipid metabolism, chloroplast integrity, and autophagy through a mechanism that involves the activation of a chloroplast quality control system.Ministerio de Economía y Competitividad BFU2015-68216-PJunta de Andalucía CVI-7336, BIO2015-74432-JI

Autophagic flux is required for the synthesis of triacylglycerols and ribosomal protein turnover in Chlamydomonas

Autophagy is an intracellular catabolic process that allows cells to recycle unneeded or damaged material to maintain cellular homeostasis. This highly dynamic process is characterized by the formation of double-membrane vesicles called autophagosomes, which engulf and deliver the cargo to the vacuole. Flow of material through the autophagy pathway and its degradation in the vacuole is known as autophagic flux, and reflects the autophagic degradation activity. A number of assays have been developed to determine autophagic flux in yeasts, mammals, and plants, but it has not been examined yet in algae. Here we analyzed autophagic flux in the model green alga Chlamydomonas reinhardtii. By monitoring specific autophagy markers such as ATG8 lipidation and using immunofluorescence and electron microscopy techniques, we show that concanamycin A, a vacuolar ATPase inhibitor, blocks autophagic flux in Chlamydomonas. Our results revealed that vacuolar lytic function is needed for the synthesis of triacylglycerols and the formation of lipid bodies in nitrogen- or phosphate-starved cells. Moreover, we found that concanamycin A treatment prevented the degradation of ribosomal proteins RPS6 and RPL37 under nitrogen or phosphate deprivation. These results indicate that autophagy might play an important role in the regulation of lipid metabolism and the recycling of ribosomal proteins under nutrient limitation in ChlamydomonasEspaña, MINECO BFU2015-68216-PEspaña, Junta de Andalucía CVI-7336 (to JLC), BIO2015-74432-JIN (to MEPP

Phosphorus Availability Regulates TORC1 Signaling via LST8 in Chlamydomonas

Target of rapamycin complex 1 (TORC1) is a central regulator of cell growth. It balances anabolic and catabolic processes in response to nutrients, growth factors, and energy availability. Nitrogen- and carbon-containing metabolites have been shown to activate TORC1 in yeast, animals, and plants. Here, we show that phosphorus (P) regulates TORC1 signaling in the model green alga Chlamydomonas (Chlamydomonas reinhardtii) via LST8, a conserved TORC1 subunit that interacts with the kinase domain of TOR. P starvation results in a sharp decrease in LST8 abundance and downregulation of TORC1 activity. A hypomorphic lst8 mutation resulted in decreased LST8 abundance, and it both reduced TORC1 signaling and altered the cellular response to P starvation. Additionally, we found that LST8 levels and TORC1 activity were not properly regulated in a mutant defective in the transcription factor PSR1, which is the major mediator of P deprivation responses in Chlamydomonas. Unlike wild-type cells, the psr1 mutant failed to downregulate LST8 abundance and TORC1 activity when under P limitation. These results identify PSR1 as an upstream regulator of TORC1 and demonstrate that TORC1 is a key component in P signaling in Chlamydomonas.España Ministerio de Economía y Competitividad (grants BFU2015-68216-P and PGC2018-099048- B-100 to J.L.C. and grant BIO2015-74432-JIN to M.E.P.-P.)National Science Foundation (CAREER award MCB-1552522 to L.M.H. and grant MCB-1616820 to J.G.U.)European Commission (grant number 750996

Improvement of nutritional properties of Cassva (Manihot esculenta) through massive analysis of gene expression

Motivation: Currently, the cassava is the basis of food for more than 1 billion people in the world. In this instance, the modification of the nutritional composition of plant foods is an urgent matter, since the basic nutritional needs of the world population are not yet covered. The identification of the transcription factors that regulate oil biosynthesis could give tools to re-direct sucrose to oil in the root of tuberculous cultures. In cassava, most of the research that has been done has focused on the tuber, with little study of the seeds and their characteristics.In Cassava the factors that direct the flow of carbon towards the different reserve tissues and determine the final composition of the tissue in the plant are not known. The proposed research line aims to deepen the knowledge of the fatty acid biosynthesis in cassava and increase the oil content of the roots. Fundamental knowledge to be able to reach the final objective of increasing the oil content. In addition to improving its nutritional value, while the amount of nutrients that contribute to the body.Methods: There are two lines of research. The computer methods are based on searching for genes involved in the biosynthesis pathway of lipid substrates through databases such as Uniref and UniProt. After a series of genes obtained from other trials, we compared their presence in the Manihot Esculenta genome and verified their function. With homologous genes, we can expand the number of candidate genes.The laboratory methods aim to develop the method of genetic transformation of cassava (Ima M Zainuddin et al., Plant Methods 2012, 8:24) in combination with Agrobacterium. From a horizontal cuttings and an in vitro culture of their apical buds, we get a mother plant from which we can obtain somatic embryos and create new seedlings to be able to transform with differentResults: The following results were obtained after a first search for genes obtained from a compilation base don papers previously made in other related organisms. From that list of candidates genes, there are genes that cease to be candidates because they are not found in Manihot esculenta, these being susy, ATP-PFK and FBAGenes that continue as candidates, for being in the genome of cassava, being PK,GPT2 and PPT1. And for the latter, new genes can be obtained, such as APE2 with identifier 16G010700.1 in JGI Phytozome. It is a translocator of triose-phosphate located in the chloroplast.Conclusions: There is a vision of the future in this line of research to be able to start from a new and broader list of genes involved in the synthesis routes of sucrose and oil that are susceptible to modification.There is still a lot to study to reach the goal, but positive results will come out

New Insights Into Sunflower (Helianthus annuus L.) FatA and FatB Thioesterases, Their Regulation, Structure and Distribution

Sunflower seeds (Helianthus annuus L.) accumulate large quantities of triacylglycerols (TAG) between 12 and 28 days after flowering (DAF). This is the period of maximal acyl-acyl carrier protein (acyl-ACP) thioesterase activity in vitro, the enzymes that terminate the process of de novo fatty acid synthesis by catalyzing the hydrolysis of the acyl-ACPs synthesized by fatty acid synthase. Fatty acid thioesterases can be classified into two families with distinct substrate specificities, namely FatA and FatB. Here, some new aspects of these enzymes have been studied, assessing how both enzymes contribute to the acyl composition of sunflower oil, not least through the changes in their expression during the process of seed filling. Moreover, the binding pockets of these enzymes were modeled based on new data from plant thioesterases, revealing important differences in their volume and geometry. Finally, the subcellular location of the two enzymes was evaluated and while both possess an N-terminal plastid transit peptide, only in FatB contains a hydrophobic sequence that could potentially serve as a transmembrane domain. Indeed, using in vivo imaging and organelle fractionation, H. annuus thioesterases, HaFatA and HaFatB, appear to be differentially localized in the plastid stroma and membrane envelope, respectively. The divergent roles fulfilled by HaFatA and HaFatB in oil biosynthesis are discussed in the light of our data.España MINECO y FEDER Projects AGL2014- 53537-R y AGL2017-83449-

Nutritional improvement of Manihot esculenta roots by boosting the lipids storage

Motivation: The human population continues to grow and it is necessary to produce more and better quality food to meet the world population's demand. Genetic engineering opens great possibilities to improve the quantity of available food. The cassava (Manihot esculenta) plant is the basis of food for more than 1 billion people in the world. All plants have genes coding for oil biosynthetic pathways and transcription factors that activate the expression of these genes. If these transcription factors are activated in other tissues, like roots, the conversion of sucrose to oil could increase. In this way, crops that accumulate sugars and starch could become more nutritious (2.2 times more energy than carbohydrates). It has been shown that starch and oil can accumulate in the same cell, as is the case for oats (Ekman et al., 2008). In this project, cassava has been chosen as a model plant because it has a high starch content in their edible roots.Methods: Two somatic embryos were obtained from mother plants with ecotype 60444. The in-vitro plants will be transformed by the vector via Agrobacterium tumefaciens. The functional annotation of the cassava proteome was carried out using Sma3s (Casimiro-Soriguer et al., 2017). This annotation will allow us to know the function of the protein-coding genes present in cassava. To know those genes involved in the synthesis of fatty acids they must be filtered. The expression of these genes in different tissues was comparated with ArrayExpress. Posible candidates will be examined in order to choose the most suitable ones to be transformed and expressed in the cassava plants.Results: From 41,381 cassava predicted proteins, 35,889 were scored, meaning Sma3s annotated 86% of the proteome. The list of possible candidates is currently around 600 genes and their expression wilI checked with public database. In vitro plants are growing and the second phase of the transformation will be begun.Conclusions: The project will (i) expand knowledge on cassava, particularly on the development of their storage organs, such as roots and seeds, as well as carbohydrate and lipid metabolism, and (ii) develop a cassava crop modification platform using genetic engineering techniques. This work aims to cover two demands of society, try to mitigate hunger, and on the other hand be able to extrapolate the scientific knowledge generated to other crops of interest to cover the current demand for vegetable oil

Measuring the Quality of Model-Driven Projects with NDT-Quality

Model-driven web engineering (MDWE) is a new paradigm which provides satisfactory results in the development of web software systems. However, as can be concluded from several research works, MDWE provokes traceability problems and the necessity of managing constraints in metamodel instances and transformation executions. The management of these aspects is usually executed manually in the most of MDWE approaches. Nevertheless, model-driven paradigm itself can offer suitable ways to manage them. This chapter presents NDT-Quality, an approach to measure the quality of web projects developed with NDT (navigational development techniques), and offers a view about the application of this tool in real web projects.Ministerio de Educación y Ciencia TIN2007-67843-C06-03Ministerio de Educación y Ciencia TIN2007-30391-