Osmoprotectants play a major role in the Portulaca oleracea resistance to high levels of salinity stress—insights from a metabolomics and proteomics integrated approach

IntroductionPurslane (Portulaca oleracea L.) is a non-conventional food plant used extensively in folk medicine and classified as a multipurpose plant species, serving as a source of features of direct importance to the agricultural and agri-industrial sectors. This species is considered a suitable model to study the mechanisms behind resistance to several abiotic stresses including salinity. The recently achieved technological developments in high-throughput biology opened a new window of opportunity to gain additional insights on purslane resistance to salinity stress—a complex, multigenic, and still not well-understood trait. Only a few reports on single-omics analysis (SOA) of purslane are available, and only one multi-omics integration (MOI) analysis exists so far integrating distinct omics platforms (transcriptomics and metabolomics) to characterize the response of purslane plants to salinity stress.MethodsThe present study is a second step in building a robust database on the morpho-physiological and molecular responses purslane to salinity stress and its subsequent use in attempting to decode the genetics behind its resistance to this abiotic stress. Here, the characterization of the morpho-physiological responses of adult purslane plants to salinity stress and a metabolomics and proteomics integrative approach to study the changes at the molecular level in their leaves and roots is presented.Results and discussionAdult plants of the B1 purslane accession lost approximately 50% of the fresh and dry weight (from shoots and roots) whensubmitted to very high salinity stress (2.0 g of NaCl/100 g of the substrate). The resistance to very high levels of salinity stress increases as the purslane plant matures, and most of the absorbed sodium remains in the roots, with only a part (~12%) reaching the shoots. Crystal-like structures, constituted mainly by Na+, Cl−, and K+, were found in the leaf veins and intercellular space near the stoma, indicating that this species has a mechanism of salt exclusion operating on the leaves, which has its role in salt tolerance. The MOI approach showed that 41 metabolites were statistically significant on the leaves and 65 metabolites on the roots of adult purslane plants. The combination of the mummichog algorithm and metabolomics database comparison revealed that the glycine, serine, and threonine, amino sugar and nucleotide sugar, and glycolysis/gluconeogenesis pathways were the most significantly enriched pathways when considering the total number of occurrences in the leaves (with 14, 13, and 13, respectively) and roots (all with eight) of adult plants; and that purslane plants employ the adaptive mechanism of osmoprotection to mitigate the negative effect of very high levels of salinity stress; and that this mechanism is prevalent in the leaves. The multi-omics database built by our group underwent a screen for salt-responsive genes, which are now under further characterization for their potential to promote resistance to salinity stress when heterologously overexpressed in salt-sensitive plants

Biomarkers prospection related to fatal yellowing in Elaeis guineensis leaves using metabolomics approach

Submitted by JÚLIO HEBER SILVA ([email protected]) on 2017-04-06T17:53:33Z No. of bitstreams: 2 Dissertação - Jorge Candido Rodrigues Neto - 2017.pdf: 4621226 bytes, checksum: 93409e3a28aced62d8c3f5dab02c58a7 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)Approved for entry into archive by Luciana Ferreira ([email protected]) on 2017-04-07T11:07:20Z (GMT) No. of bitstreams: 2 Dissertação - Jorge Candido Rodrigues Neto - 2017.pdf: 4621226 bytes, checksum: 93409e3a28aced62d8c3f5dab02c58a7 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)Made available in DSpace on 2017-04-07T11:07:20Z (GMT). No. of bitstreams: 2 Dissertação - Jorge Candido Rodrigues Neto - 2017.pdf: 4621226 bytes, checksum: 93409e3a28aced62d8c3f5dab02c58a7 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-03-03Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPESOil palm (Elaeis guineensis) is the world’s major source of vegetable oil and it has been able to adapt to the Brazilian subtropical area. Its growth, largely done in Para, is affected by Fatal Yellowing (FY), a condition that can cause plant’s death and has unknown cause. The aim for this master’s project was to prospect and identify, using a metabolomics approach, possible biomarkers of FY. To accomplish this study, for the first time different transport and extraction methods were evaluated in order to verify the metabolic profile stability in this species. Significant differences were noted and described using a metabolic fingerprinting approach, with ultra high precision liquid chromatography – mass spectrometry (UHPLC-MS) as the chemical analysis and ANOVA simultaneous component analysis (ASCA) as the multivariate statistic tool. After this study, leaves with and without FY symptoms were transported using the previously optimizes protocol, analyzed and five potential biomarkers were identified and related to their metabolic pathways, using PCA as the chemometric tool. Finally, for the first time, the use of advanced analytical techniques as MALDI imaging, which has been highlighted as a powerful tool for identification of chemical compounds present on tissue surface with spatial localization, has been applied to oil palm leaves in order to perform a metabolic screening and search for the previously identified biomarkers. An analytical protocol was established for analysis with and without matrix application, for a wide range mass coverage and one of the possible biomarkers was detected using the matrix-free approach.O dendê, fruto do dendezeiro (Elaeis guineensis) é a maior fonte de óleo vegetal do mundo e teve boa adaptação ao clima subtropical brasileiro. Seu cultivo no Brasil, que tem maior extensão no Pará, é afetado pelo Amarelecimento Fatal (AF), uma condição que pode provocar a morte da planta e tem causa desconhecida. O objetivo deste projeto de mestrado foi prospectar e identificar marcadores químicos relacionados ao AF utilizando uma abordagem metabolômica. Para que o estudo dessa causa fosse realizado, pela primeira vez foram avaliados diferentes métodos de transporte e extração de folhas para verificar a estabilidade do perfil metabólico desta espécie. Diferenças significativas foram observadas utilizando a estratégia de metabolic fingerprinting, com análise dos metabólitos por cromatografia de ultra alta eficiência – espectrometria de massas (UHPLC-MS) e análise quimiométrica dos dados por análise de componente simultâneo e análise de variância (ASCA). Após este estudo, folhas com e sem sintomas de AF foram transportadas utilizando protocolo otimizado anteriormente, analisadas e cinco potenciais biomarcadores foram identificados e relacionados as suas respectivas vias metabólicas, utilizando a análise de componentes principais (PCA) como ferramenta quimiométrica. Por fim, fez-se uso da recente e avançada técnica de imagem química em espectrometria de massas, com ionização por dessorção a laser assistida por matriz (MALDI-MS Imaging), que vem se destacando como uma poderosa ferramenta para a identificação de compostos químicos presentes na superfície de um tecido com localização espacial e foi utilizada pela primeira vez em um screening de metabólitos em folhas de dendê na busca dos marcadores previamente identificados. Um protocolo analítico foi desenvolvido para análise com aplicação de matriz e sem aplicação de matriz, com o intuito de abranger uma maior faixa de massas e um dos possíveis marcadores foi detectado utilizando a técnica de imagem sem matriz

Differential microRNA profile in operational tolerance: a potential role in favoring cell survival

Operational tolerance (OT) is a state of graft functional stability that occurs after at least 1 year of immunosuppressant withdrawal. MicroRNAs (microRNA) are small non-coding RNAs that downregulate messenger RNA/protein expression of innumerous molecules and are critical for homeostasis. We investigated whether OT in kidney transplantation displays a differential microRNA profile, which would suggest that microRNAs participate in Operational Tolerance mechanisms, and may reveal potential molecular pathways. Methods: We first compared serum microRNA in OT (n = 8) with chronic rejection (CR) (n = 5) and healthy individuals (HI) (n = 5), using a 768-microRNA qPCR-panel. We used the Thermo Fisher Cloud computing platform to compare the levels of microRNAs in the OT group in relation to the other study groups. We performed validation experiments for miR-885-5p, by q-PCR, in a larger number of study subjects (OT = 8, CR = 12, HI = 12), as individual samples. Results: We detected a differential microRNA profile in OT vs. its opposing clinical outcome-CR-suggesting that microRNAs may integrate transplantation tolerance mechanisms. Some miRNAs were detected at higher levels in OT: miR-885-5p, miR-331-3p, miR-27a-5p vs. CR; others, we found at lower levels: miR-1233-3p, miR-572, miR-638, miR-1260a. Considering highly predicted/experimentally demonstrated targets of these miRNAs, bioinformatics analysis revealed that the granzyme B, and death receptor pathways are dominant, suggesting that cell death regulation integrates transplantation tolerance mechanisms. We confirmed higher miR-885-5p levels in OT vs. CR, and vs. HI, in a larger number of subjects. Conclusions: We propose that epigenetics mechanisms involving microRNAs may integrate human transplantation tolerance mechanisms, and regulate key members of the cell death/survival signaling. miR-885-5p could favor cell survival in OT by diminishing the levels of CRADD/RAIDD and CASP3. Nonetheless, given the nature of any complex phenomenon in humans, only cumulative data will help to determine whether this microRNA differential profile may be related to the cause or consequence of operational tolerance10CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPES465434/2014-2CAPES-PROEX-33002010061P

Myocardial Infarction-Associated Transcript, a Long Noncoding RNA, Is Overexpressed During Dilated Cardiomyopathy Due to Chronic Chagas Disease

International audienceno abstrac

Study of environmental burden of lead in children using teeth as bioindicator

The south region of Sao Paulo city hosts the Guarapiranga dam, responsible for water supply to 25% of the city population. Their surroundings have been subject to intense and irregular occupation by people from very low socioeconomics classes. Measurements undertaken on sediment and particulate materials in the dam revealed concentrations of lead. copper, zinc and cadmium above internationally accepted limits. Epidemiological and toxicological studies undertaken by the World Health Organization in individuals exhibiting lead concentrations in blood, near or below the maximum recommended (10 mu g dl(-1)), surprisingly revealed that toxic effects are more intense in individuals belonging to low socioeconomics classes. Motivated by these facts, we aimed at the investigation of chronic incorporation of lead. as well as the use of our BIOKINETICS code, which is based on an accepted ICRP biokinetics model for lead, in order to extrapolate the results from teeth to other organs. The focus of our data taking was children from poor families, living in a small, restrict and allegedly contaminated area in Sao Paulo city. Thus, a total of 74 human teeth were collected. The average concentration of lead in teeth of children 5 to 10 years old was determined by means of a high-resolution inductively coupled plasma mass spectrometer (ICP-MS). For standardization of the measurements, an animal bone certified material (H-Animal Bone), from the International Atomic Energy Agency, was analyzed. The amount of lead in children living in the surroundings of the dam, was approximately 40% higher than those from the control region, and the average lead concentration was equal to 1.3 mu g g(-1) approximately. Grouping the results in terms of gender, tooth type and condition, it was concluded that a carious molar of boys is a much more efficient contamination pathway for lead, resulting in concentrations 70% higher than in the control region. We also inferred the average concentrations of lead in other organs of these children, by making use of our BIOKINETIC code. (C) 2008 Elsevier Ltd. All rights reserved