Characterization of AtDGK2 in relation to Contact Sites

Contact Sites are conserved cellular regions where two membranes of different organelles are very close but not merged. Contact sites between the endoplasmic reticulum (ER) and the plasma membrane (ER-PM CS) play important roles in metabolic functions. We have identified AtDGK2 (Diacylglycerol kinase 2) as an interactor of SYT1 (Synaptotagmin1), which is a protein located at ER-PM CS. DGKs phosphorylate diacylglycerol to produce phosphatidic acid, both important signalling molecules. Arabidopsis thaliana has seven AtDGKs, but only AtDGK1 and AtDGK2 present an ER transmembrane domain, the rest are cytoplasmic. We have analysed the subcellular localization and functions of these two proteins.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. BIO2017-82609-

Propuesta de un plan de mantenimiento preventivo para la caldera de diésel York Shipley instalada en Planta de sub-producto COESA, de Avícola La Estrella, S.A, en el periodo comprendido de agosto a noviembre, 2015

El presente trabajo se realizó en el área de calderas de la Planta de Sub-producto COESA de Avícola La Estrella, S.A., ubicada en el Km 29 ½ de la carretera norte. Esta pequeña planta comenzó operaciones a mediados del mes de mayo de presente año. En la planta se realiza el proceso de elaboración de harina de pollo de todas las aves que son desechadas en las galeras de la empresa. En el inicio del presente trabajo se plantearon los objetivos (general y específicos) cuyo propósito es la mayor optimización productiva del equipo, de la misma manera en el planteamiento del problema se expone que los paros repentinos de la máquina son el principal problema por la falta de un adecuado mantenimiento. En cuanto al marco referencial se establecieron las respectivas teorías, definiciones, las especificaciones de las leyes con las que regir el presente estudio, la localización de la empresa y la especificación temporal en la que se realizó. Este estudio tiene un enfoque de carácter mixto ya que se describen y analizan los datos que generan la información encontrada de la máquina. De la misma manera se estableció el universo, población y muestra que corresponde a la empresa, la planta de subproducto y la máquina evaluada respectivamente y luego las herramientas de investigación que se utilizaron como entrevista, observación y métodos como el árbol de problemas y de fallos y la metodología HAZOP. En el desarrollo se caracteriza el proceso de producción por medio del diagrama de flujo de la norma ISO, se analizan las fallas con el árbol de problemas y árbol de fallo, se implementa la metodología HAZOP en donde se encuentra la “presión” como el mayor factor de riesgo y finalmente la aplicación del correspondiente “Manual MPP” para la caldera con un breve análisis de los costos de mantenimiento, los resultados de la entrevista y la observación aplicada. Finalmente la conclusión basada en los objetivos que se establecieron y luego las respectivas recomendaciones de mejoras para la planta y la caldera en estudio

Undercovering the molecular mechanisms of lipid signalling at ER-PM contact sites in tomato (Solanum lycopersicum) under abiotic stress conditions

Abiotic stresses cause large reductions in crop production. Therefore, is important to understand how plants respond in order to develop varieties with increased resistance. Lipid-transport proteins (LTP) are emerging as key players of lipid signaling in response to numerous stresses. Specifically, SYT1, a protein first identified by its role in abiotic stress tolerance, is now recognized as an endoplasmic reticulum-plasma membrane contact site tether capable. Our recent data support that SYT1 in involved on non-vesicular lipid-transport of diacyl glycerol (DAG) through its SMP domain. This data together with the interaction of SYT1 with a diacyl glycerol kinase (DGK) suggest a lipid signaling pathway where the product of phospholipase C, diacylglycerol, might be simultaneously translocated from the plasma membrane to the endoplasmic-reticulum by SYT1 and phosphorylated to phosphatidic acid by DGK at the plasma membrane. Using in vitro biochemical approaches we are investigating the affinity of specific lipid species transported by SYT1 using lipid-competition assays, where a fluorescent lipid competes for SYT1 binding-pocket with different lipid species. Using bioinformatic we are obtaining insight into the lipid signal pathway involving PHOSPHOLIPASE C (PLC), DIACYLGLYCEROL KINASE (DGK) and SYNAPTOTAGMIN1 (SYT1) in tomatoUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Role of Arabidopsis DGK1 and DGK2 in cold stress

There are regions, present in all eukaryotic cells, where the membranes of two different organelles are very close (10-30nm), but without fusion, due to proteins which act as tether. These regions are named Membrane Contact Sites (MCS), as for example those formed by endoplasmic reticulum (ER) and plasma membrane (PM). ER-PM CS play important roles in communication between membranes, lipid homeostasis and Ca2+ influx. When a plant is challenge with a stress, phospholipase C is activated at PM producing diacylglycerol (DAG) and inositol phosphates from the hydrolysis of PIP(4,5)P2 or PI4P. DAG is then phosphorylated by diacylglycerol kinases (DGKs) producing phosphatidic acid (PA). Both, DAG and PA, are molecules involved in signalling (Arisz et al., 2009). The genome of Arabidopsis thaliana contain 7 genes encoding DGKs. Most of them are predicted to be cytosolic, with only DGK1 and DGK2 are anchored to the ER due a transmembrane domain. Using different approaches (Co-Immunoprecipitation, confocal microscopy, FRET, Tap-tag…), our group has uncover, that AtDGK1 and AtDGK2 (Diacylglycerol kinase 1, AT5G07920 and Diacylglycerol kinase 2, At5g63770) form a complex with the lipid transport protein located at ER-PM CS known as Synaptotagmin1 (SYT1, At2g20990) (Pérez-Sancho et al., 2015). SYT1 is able to bind preferentially DAG (Ruiz-Lopez et al., 2021), which support the idea that SYT1, DGK1, and DGK2 function coordinated to regulate the levels of DAG at the PM. DGK1 and DGK2 are induced upon low temperatures and found that dgk2 mutants show reduced root growth in low temperature and have reduced freezing tolerance. Our studies suggest that DGK1 and DGK2 act in concert with SYT1 to regulate the production of DAG and PA at ER-PM CS and highlight the importance of these proteins for the correct response to stress.The authors acknowledge the support by: (1) Ministerio de Ciencia e Innovación BIO2017-82609-R, PGC2018-098789-B-100; (2) Ministerio de Economía, Industria y Competitividad (BES-2015-071256, RyC-2013-12699). Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

How are DGK1 and DGK2 involved in membrene contact sites?

Eukaryotic cells have regions of interaction between two organelles where some proteins, which act as tether, bring both membranes closer (10-30 nm) without fusion, named membrane contact sites (MCS). Two organelles that can form MCS are endoplasmic reticulum (ER) and plasma membrane (PM). ER-PM CS play important metabolic functions such as communication between both membranes, lipid homeostasis and Ca2+ influx. Our group has identified that AtDGK1 and AtDGK2 (Diacylglycerol kinase 1, AT5G07920 and Diacylglycerol kinase 2, At5g63770) form a complex with a well-known protein located at ER-PM CS, Synaptotagmin1 (SYT1, At2g20990). Upon perception of stress, phospholipase C (PLC) is activated at the plasma membrane to hydrolyse PIP(4,5)P2 or PI4P in order to generate DAG and inositol phosphates. Diacylglycerol (DAG) is phosphorylated by diacylglycerol kinases (DGKs) to produce phosphatidic acid (PA). DAG and PA are important cell signalling molecules. There are seven DGKs encoded in Arabidopsis thaliana genome, but only DGK1 and DGK2 have a transmembrane domain that anchors them to the endoplasmic reticulum, the rest are cytoplasmic. DGK1 and DGK2 appear to play a role in stress response as both are induced by exposure to low temperatures and wounding. Also, we found that dgk2 knockout mutant produces lower resistance to freezing. Using confocal microscopy, we have analysed the subcellular localization of these two proteins and investigated their interaction with SYT1 and between them using FRET and co-immunoprecipitation studies. Additionally, we report that the mutation of DGK1 is lethal in homozygosity. Our studies suggest that DGK1 and DGK2 act in concert with SYT1 to regulate the production of PA at ER-PM CS and highlight the importance of these proteins for the correct response to stress tolerance.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

SMP-CONTAINING PROTEINS AT MEMBRANE CONTACT SITES: SUBCELLULAR LOCALIZATION AND CHARACTERIZATION.

Membrane contact sites (MCS) are microdomains where two membranes of two different organelles are in close apposition, but they do not fuse. MCS are essential for non-vesicular transport of lipids. This lipid transport is mediated by several families of proteins which all of them contain a lipid transport domain, as the synaptotagmin-like mitochondrial lipid-binding (SMP) domain. The most studied SMP protein is Arabidopsis SYT1 which is known to be involved in tolerance to multiple abiotic stresses. Later studies in other SMP proteins of the same family have shown that SYT1 and homologous such as SYT3 or SYT5 gave similar results. However, little information is available about the role other SMP proteins in plants. We have studied the occurrence of additional SMP proteins in A. thaliana and S. lycopersicum. In order to identify these proteins, SMP sequences from human and yeast were used to identify their remote orthologues in A. thaliana and S. lycopersicum, allowing the identification of several putative encoding SMP domains. We have found that some of the identified proteins are exclusive of plants as they do not have direct orthologs in yeast nor human. Transient expression in N. benthamiana leaves followed by confocal microscopy was used to study the subcellular localization of these proteins. Our results show that some of these proteins are localized at ER-Golgi contact sites and two other proteins at ER-Chloroplast sites. Finally, to determine whether these proteins are involved in abiotic stress tolerance, we have analysed the root growth and seed germination rates of Arabidopsis mutants for these genes under different conditions. Some of these mutants have shown different germination rates in media supplemented with NaCl and different rates of expanded cotyledons in media supplemented with ABA. These results suggest that some these proteins may be implicated in abiotic stress signalling through an ABA-dependent pathway.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. This work is supported by grants from: Ministerio de Ciencia, Innovación y Universidades (grant PGC2018-098789-B-I00), UMA-FEDER (grant UMA18-FEDERJA-154) and Ministerio de Ciencia e Innovación (BIO2017-82609-R)

Recubrimientos recomendables por razones de durabilidad, a disponer en estructuras de hormigón sometidas a la clase específica de exposición Qb (ataque químico de intensidad media)

Es una realidad cada vez más aceptada que la durabilidad del hormigón es una propiedad igual de importante que la resistencia mecánica o la estabilidad de volumen. No es el objeto del presente trabajo ahondar en las causas de esta evidencia sino en contribuir a hacer del diseño de la durabilidad una materia incorporada al quehacer diario de los técnicos y especialistas. Solo si la durabilidad de una estructura se puede proyectar y verificar, será posible conseguir vidas útiles con una cierta garantía o seguridad en que se alcanzarán los periodos de servicio que se especifiquen. En el diseño de la durabilidad se ha dedicado mucho tiempo en el pasado a aclarar los mecanismos de ataque (por ejemplo: por sulfatos o por reacción árido-álcali) o como realizar ensayos acelerados en estos casos y también en el caso concreto de la corrosión de la armadura. En el caso de la corrosión, la envergadura de los costes de reparaciones ha estimulado la publicación de modelos y ensayos que, si bien necesitan todavía calibración, al menos suponen una cierta ayuda para el proyectista

Dental approach for Apert syndrome in children : a systematic review

Apert Syndrome (AS), or type I acrocephalosyndactyly, is a rare, congenital craniosynostosis condition resulting from missense mutations in the gene encoding fibroblast growth factor receptor 2. It is characterized by three specific clinical features: brachycephalic skull; midface hypoplasia, and limb abnormalities (syndactyly of hands and feet). The disorder exhibits variable presentations in bones, brain, skin, internal organs, and in the oral/maxillofacial region. The aim of the present paper was to show the main results from a systematic review of AS. A search of the literature was performed from April to June 2016 in five electronic databases. Clinical interventional or observational studies, reviews, and case reports were included. The present systematic review was carried out strictly following PRISMA and Cochrane Collaboration criteria. A total of 129 potential references were identified. After reviewing titles and abstracts, 77 of these did not meet the desired criteria and were discarded. The full text of the remaining 52 manuscripts was critically screened. Finally, 35 relevant papers were identified for inclusion in the present systematic review and classified according to topic type. According to the information gathered, dentistry practitioners must be able to supply an early diagnosis through the recognition of AS clinical features and provide correct oral management. Additionally, they should be integrated in a multidisciplinary medical care team in order to improve the quality of life of the affected patients

Mussel-Inspired Lego Approach for Controlling the Wettability of Surfaces with Colorless Coatings

The control of surface wettability with polyphenol coatings has been at the forefront of materials research since the late 1990s, when robust underwater adhesion was linked to the presence of L-DOPA—a catecholic amino acid—in unusually high amounts, in the sequences of several mussel foot proteins. Since then, several successful approaches have been reported, although a common undesired feature of most of them is the presence of a remnant color and/or the intrinsic difficulty in fine-tuning and controlling the hydrophobic character. We report here a new family of functional catechol-based coatings, grounded in the oxidative condensation of readily available pyrocatechol and thiol-capped functional moieties. The presence of at least two additional thiol groups in their structure allows for polymerization through the formation of disulfide bonds. The synthetic flexibility, together with its modular character, allowed us to: (I) develop coatings with applications exemplified by textiles for oil-spill water treatment; (II) develop multifunctional coatings, and (III) fine-tune the WCA for flat and textile surfaces. All of this was achieved with the application of colorless coatings.Fil: Casagualda, Carolina. Universitat Autònoma de Barcelona; EspañaFil: Mancebo Aracil, Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentina. Universitat Autònoma de Barcelona; EspañaFil: Moreno Villaecija, Miguel Angel. Universitat Autònoma de Barcelona; EspañaFil: López Moral, Alba. Universitat Autònoma de Barcelona; EspañaFil: Alibés, Ramon. Universitat Autònoma de Barcelona; EspañaFil: Busqué, Félix. Universitat Autònoma de Barcelona; EspañaFil: Ruiz Molina, Daniel. Universitat Autònoma de Barcelona; Españ

Localization and characterization of SMP-containing proteins in Membrane Contact Sites

Membrane contact sites (MCS) are discrete regions where two membranes from different organelles are closely apposed (10-30 nm). In those regions, non-vesicular transfer of lipids takes place to ensure proper organelle functioning. Arabidopsis SYT1 is one of the best characterized MCS protein, and it plays a relevant role in tolerance to abiotic stresses. SYT1 is a SMP (synaptotagmin-like mitocondrial lipid binding domain) containing protein localized at ER-PM contact sites. Recent studies suggest that this protein transfer glycerolipids between these two membranes. However, little is known about other SMP-containing proteins in plants, as their localization or their role in abiotic stress. We have focused on studying the rest of SMP-containing proteins in Arabidopsis thaliana and Solanum lycopersicum. To identify them, human E-Syt1 sequence was used to find the remote orthologues in plants. An interesting highlight of those results was that some SMP-containing proteins are exclusive from plants, there are no orthologues in human nor yeast. The subsequent step was the study of their subcellular location, that was carried out in Nicotiana benthamiana by transient expression of the SMP-containing proteins from Arabidopsis and Solanum, followed by confocal microscopy imaging. We have found that those proteins locate in different MCS across the cell: SYT6, NTMC2T6 and Tex2 localise in ER-Golgi contact sites, NTMC2T5 in ER-Chloroplast contact sites, and we have also confirmed that Solanum CLB1 and SYT5 localized at ER-PM contact sites as their Arabidopsis counterparts. Additionally, we have analysed the root growth, seed germination rates and fully expanded cotyledons of Arabidopsis mutants for these genes in media supplemented with salt or ABA, and our results suggest that some of these proteins might be implicated in abiotic stress signalling through an ABA pathway.This work is supported by grants from: Ministerio de Ciencia, Innovación y Universidades (grant PGC2018-098789-B-I00), UMA-FEDER (grant UMA18-FEDERJA-154) and Ministerio de Ciencia e Innovación (BIO2017-82609-R), and meeting assistance was granted by Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech