Using lipidomics to reveal details of lipid accumulation in developing seeds from oilseed rape (Brassica napus L.)

With dwindling available agricultural land, concurrent with increased demand for oil, there is much current interest in raising oil crop productivity. We have been addressing this issue by studying the regulation of oil accumulation in oilseed rape (Brassica napus L). As part of this research we have carried out a detailed lipidomic analysis of developing seeds. The molecular species distribution in individual lipid classes revealed quite distinct patterns and showed where metabolic connections were important. As the seeds developed, the molecular species distributions changed, especially in the period of early (20 days after flowering, DAF) to mid phase (27DAF) of oil accumulation. The patterns of molecular species of diacylglycerol, phosphatidylcholine and acyl-CoAs were used to predict the possible relative contributions of diacylglycerol acyltransferase (DGAT) and phospholipid:diacylglycerol acyltransferase to triacylglycerol production. Our calculations suggest that DGAT may hold a more important role in influencing the molecular composition of TAG. Enzyme selectivity had an important influence on the final molecular species patterns. Our data contribute significantly to our understanding of lipid accumulation in the world’s third most important oil crop

Circulación e intercambio en el poblamiento y la explotación de la alta montaña del Pirineo en los milenios V-IV ANE

Los datos arqueológicos que presentamos indican que las áreas de alta montaña del Pirineo axial fueron objeto de un proceso de ocupación y explotación económica continuada a lo largo del Neolítico. La reiterada ocupación de la Cueva del Sardo de Boí, situada a 1790 m de altitud, en el Parque Nacional de Aigüestortes i Estany de Sant Maurici, desde inicios del V hasta mediados del III milenio ANE, nos permite apoyar esta hipótesis. El estudio de los materiales líticos amortizados en el yacimiento parece indicar la existencia de patrones de movilidad regional de los grupos neolíticos pirenaicos, así como el contacto con otros grupos al exterior de la cordillera

Generation and Characterization of a Novel Recombinant Antibody Against 15-Ketocholestane Isolated by Phage-Display

The employment of monoclonal antibodies (Mabs) to identify disease-associated biomarkers in clinical samples represents the underlying principle for many diagnostic tests. To date, these have been principally developed for protein targets with few reported applications for lipids due to their hydrophobicity and poor immunogenicity. Oxysterols represent a family of lipids implicated in diverse human diseases where Mab-based detection assays could have a profound effect on their utility as clinical biomarkers. These are usually identified in patients’ samples by mass- spectrometry based approaches. Here, we describe an antibody phage-library based screening methodology for generating a recombinant monoclonal antibody (RAb) targeting the oxysterol-15-ketocholestane (15-KA), a lipid implicated in multiple sclerosis and Autoimmune Encephalomyelitis (EAE). The antibody is highly specific for 15-KA and shows little or no binding activity for other closely related oxysterols. We employ RAb2E9 to address the controversy over whether 15-KA is a true biomarker for MS/EAE and show that 15-KA is undetectable in serum taken from mice with EAE using antibody based detection methodologies; a finding confirmed by mass-spectrometry analysis. This study demonstrates the technical feasibility of using phage display to isolate highly specific antibodies against poorly immunogenic, small molecule lipids

La explotación de las cimas. Ocupación e impacto humano en las zonas alpinas de los Pirineos al final del Neolítico

En los últimos años se ha constatado arqueológicamente la presencia humana en el Pirineo axial desde inicios del Holoceno, que se incrementa especialmente durante el Neolítico. Con un escaso desfase con respecto a la cronología de las primeras ocupaciones neolíticas del Piedemonte y del Prepirineo, se han documentado diversos yacimientos en fondos de valle del área axial y en laderas entre los 1400 y los 1800 metros de altitud, ocupados desde el V y IV milenios cal ANE. Las últimas investigaciones confirman, además, un incremento del número de asentamientos durante el tercer milenio cal ANE en diversos puntos de la región central de los Pirineos en cotas que, en ocasiones, superan los 2.300 metros de altura. Paralelamente, los datos paleoambientales muestran las primeras señales de impacto humano sobre el medio, como por ejemplo descensos de las formaciones forestales o un incremento de las evidencias de las aperturas de pastos. En definitiva, parece que es a partir del final del Neolítico cuando se establece una explotación ganadera de las áreas alpinas y la franja superior de los pisos subalpinos, iniciando un proceso que ganará en intensidad durante el II milenio cal ANE. Esta presentación aborda la discusión del fenómeno del poblamiento en las zonas altas de la sierra, procurando evitar apriorismos relacionados con el determinismo medioambiental. Para eso, entendemos imprescindible la comparación y contrastación de los datos arqueológicos y la información paleoecológica, con el objetivo de entender, de forma integrada, la evolución del paisaje, de las sociedades y del impacto que éstas produjeron sobre el territorio.Peer reviewe

Interacción entre clima y ocupación humana en la configuración del paisaje vegetal del Parque Nacional de Aigüestortes i Estany de Sant Maurici a lo largo de los últimos 15.000 años

The vegetation of the National Park of Aigüestortes i Estany de St Maurici is the result of an interaction between climate, plant community dynamics and the human occupation of the territory. The OCUPAproject aimed to reconstruct this interaction across the last millennia combining methods from palaeoecology and archaeology. The study focused primarily on the Sant Nicolau valley and built on the multidisciplinary analysis of the sedimentary archive of two lakes (Llebreta and Redó) and a number of archaeological sites located in shelters and outdoors. There is archaeological evidence of human presencesince 9000 yr cal BP, and a continuous record since 7500 yr cal BP. At early stages, humans transformed the surroundings of the shelters occupied and lithic tools indicate contacts with locations far away (i.e.,the Ebro plains). Since more than 3000 years ago, there has been human impact on the vegetation withoutinterruption until present. Initially, the impacts were mostly related to livestock: use of fire to open grazing lands, soil erosion and, during the medieval period, forestry and eutrophication of lakes. The agriculture impact in the lower part of the valley (e.g., Llebreta) occurred about 2100 yr ago, although some cereal grains and tools for harvesting have been found for the Neolithic. In the medieval period, the impact was higher than during the last centuries. In general, the changes in the human land use approximately follow the major changes in climate, but the specific causal link is likely related to the social and cultural dynamics of a broader territory since the Neolithic

MS-based lipidomics of human blood plasma: a community-initiated position paper to develop accepted guidelines

Human blood is a self-regenerating lipid-rich biological fluid that is routinely collected in hospital settings. The inventory of lipid molecules found in blood plasma (plasma lipidome) offers insights into individual metabolism and physiology in health and disease. Disturbances in the plasma lipidome also occur in conditions that are not directly linked to lipid metabolism; therefore, plasma lipidomics based on MS is an emerging tool in an array of clinical diagnostics and disease management. However, challenges exist in the translation of such lipidomic data to clinical applications. These relate to the reproducibility, accuracy, and precision of lipid quantitation, study design, sample handling, and data sharing. This position paper emerged from a workshop that initiated a community-led process to elaborate and define a set of generally accepted guidelines for quantitative MS-based lipidomics of blood plasma or serum, with harmonization of data acquired on different instrumentation platforms across independent laboratories as an ultimate goal. We hope that other fields may benefit from and follow such a precedent

A mutation of EPT1 (SELENOI) underlies a new disorder of Kennedy pathway phospholipid biosynthesis.

Mutations in genes involved in lipid metabolism have increasingly been associated with various subtypes of hereditary spastic paraplegia, a highly heterogeneous group of neurodegenerative motor neuron disorders characterized by spastic paraparesis. Here, we report an unusual autosomal recessive neurodegenerative condition, best classified as a complicated form of hereditary spastic paraplegia, associated with mutation in the ethanolaminephosphotransferase 1 (EPT1) gene (now known as SELENOI), responsible for the final step in Kennedy pathway forming phosphatidylethanolamine from CDP-ethanolamine. Phosphatidylethanolamine is a glycerophospholipid that, together with phosphatidylcholine, constitutes more than half of the total phospholipids in eukaryotic cell membranes. We determined that the mutation defined dramatically reduces the enzymatic activity of EPT1, thereby hindering the final step in phosphatidylethanolamine synthesis. Additionally, due to central nervous system inaccessibility we undertook quantification of phosphatidylethanolamine levels and species in patient and control blood samples as an indication of liver phosphatidylethanolamine biosynthesis. Although this revealed alteration to levels of specific phosphatidylethanolamine fatty acyl species in patients, overall phosphatidylethanolamine levels were broadly unaffected indicating that in blood EPT1 inactivity may be compensated for, in part, via alternate biochemical pathways. These studies define the first human disorder arising due to defective CDP-ethanolamine biosynthesis and provide new insight into the role of Kennedy pathway components in human neurological function

Deciphering lipid structures based on platform-independent decision rule sets

We developed decision rule sets for Lipid Data Analyzer (LDA; http://genome.tugraz.at/lda2), enabling automated and reliable annotation of lipid species and their molecular structures in high-throughput data from chromatography-coupled tandem mass spectrometry. Platform independence was proven in various mass spectrometric experiments, comprising low- and high-resolution instruments and several collision energies. We propose that this independence and the capability to identify novel lipid molecular species render current state-of-the-art lipid libraries now obsolete

Settlement, Exploitation and Environment of the Alpine and Subalpine Niches in the Central Pyrenees during the First Half of the Holocene

[EN] This paper presents the results of the studies undergo at the Cova del Sardo and Abric de l’Estany de la Coveta I, two archaeological sites placed in the National Park of Aigüestortes and Estany de Sant Maurici. Both sites have been object of multiproxy analyses inside a long‐term research program in archaeology that promotes surface surveys and excavations in the head of Noguera Pallaresa and Noguera Ribagorçana basins, in the Central Southern Pyrenees. The studies shown different variables that suggest an anthropogenic impact on the vegetation during the first half of the Neolithic occupation at Cova del Sardo, that took place during the Holocene Climatic Optimum. The presence of cereals seeds in two Neolithic phases suggests the possibility of some kind of local agriculture, although this hasn’t been confirmed by pollen studies. Probably livestock it was the main economic activity in this site. In latter Neolithic phases at Cova del Sardo a recovery of a closed forest can be seen, while there is a climatic deterioration. Paradoxically, at this moment the occupation and exploitation pattern turns to a major emphasis towards the alpine pastures, with little camps around the lakes and glacial cirques just at the beginning of secondary basins. The palaeoecological study of archaeological contexts is very helpful to understand the local phenomena of environmental impact because of economic activities.[ES] Se presentan los resultados del estudio interdisciplinar realizado en Cova del Sardo y Abric de l’Estany de la Coveta I, ambos yacimientos en el entorno del Parque Nacional d’Aigüestortes i Estany de Sant Maurici. Estos se enmarcan en un amplio proyecto de prospección y excavación arqueológica entre las cabeceras de los valles de la Noguera Pallaresa y la Noguera Ribagorçana, en el Pirineo Central. Los estudios cubren la primera mitad del Holoceno y permiten documentar un impacto ambiental a nivel local durante la primera fase de ocupación neolítica, coincidente con el último Óptimo Climático. La presencia de cereales en el registro plantea la posibilidad de una agricultura local, no confirmada por los estudios polínicos. La ganadera fue probablemente la actividad principal. En las fases sucesivas se observa la recuperación del bosque cerrado, a la vez que se produce un deterioro climático y el patrón de ocupación y gestión del territorio cambia hacia una explotación de los pastos de alta montaña y los lagos, y bases de circos de las cabeceras de las cuencas secundarias. El estudio paleoecológico de contextos arqueológicos ha resultado de gran ayuda para la comprensión de fenómenos locales de impacto sobre el entorno como resultado de actividades económicas.Esta investigación ha sido financiada en el marco de los proyectos HAR2008‐01984/HIST del MICINN y 088‐2009OCUPA de la Red de Parques Nacionales, así como por diversas aportaciones directas del PNAESM entre los años 2004 y la actualidad. La investigación de F. Antolín se integra en el marco de AGREST (2009 SGR 734) y F.B. pertenece al “2009 SGR 813”, proyectos de los ‘Grupos de Investigación Reconocidos’, modalidad ‘consolidado’, de AGAUR (Generalitat de Catalunya). A. Ballesteros ha sido beneficiaria de una beca FI de la Generalitat de Catalunya y F. Antolín actualmente goza de una beca JaePre.Peer reviewe

The Beginning of High Mountain Occupations in the Pyrenees. Human Settlements and Mobility from 18,000 cal BC to 2000 cal BC

During the last two decades, the archaeological research carried out in the Pyrenees challenged the traditional images of the past in this mountain area. The archaeological sequence of the range goes back and sites like Balma Margineda, treated until recently as an exception, now are seen as part of more global process. Actual data suggest that main valleys of the Pyrenean frequented by humans at the end of the last glacial period, with sites slightly over 1000 o.s.l. After the Younger Dryas, the human presence ascended to alpine and subalpine areas, in accordance with current archaeological data. The Neolisitation process was early in some hillsides, with intense remains of farming and pastoralism in many sites from dated in the second half of the 6th millennia cal BC. Human settlements like Coro Tracito, Els Trocs and El Sardo confirm the full introduction of agrarian activity in the central part of the Pyrenees between 5300 and 4600 cal BC. After 3500/3300 cal BC the indices oh sheepherding rises to alpine areas, with an abrupt increase of known archaeological sites in alpine areas, above the current timberline. This phenomena, as well as the signs of anthropic disturbance of the alpine environment in sedimentary sequences, suggests a more stable and ubiquitous human presence, probably largely associated with the development of mobile herding practices.This paper has been carried out in the frame of the GAAM/AGREST research activity. More specifically, this study is part of the projects “Análisi ecológico de la culturización del paisaje de alta montaña desde el Neolítico: los Parques Nacionales de montaña como modelo (CUL-PA)” funded by the Ministry of Agriculture, Food and Environment (Spain) and directed by J. Catalán and “Modelización de los espacios prehistóricos de montaña. Un SIG del patrimonio arqueológico y los territorios pastoriles” (HAR2015-66780-P, MINECO/FEDER) funded by the Ministry of Economy and Competitiveness (Spain) and directed by E. Gassiot.Peer reviewe