Impact of Heavy Metals on Cold Acclimation of Salix viminalis Roots.

In nature, plants are exposed to a range of climatic conditions. Those negatively impacting plant growth and survival are called abiotic stresses. Although abiotic stresses have been extensively studied separately, little is known about their interactions. Here, we investigate the impact of long-term mild metal exposure on the cold acclimation of Salix viminalis roots using physiological, transcriptomic, and proteomic approaches. We found that, while metal exposure significantly affected plant morphology and physiology, it did not impede cold acclimation. Cold acclimation alone increased glutathione content and glutathione reductase activity. It also resulted in the increase in transcripts and proteins belonging to the heat-shock proteins and related to the energy metabolism. Exposure to metals decreased antioxidant capacity but increased catalase and superoxide dismutase activity. It also resulted in the overexpression of transcripts and proteins related to metal homeostasis, protein folding, and the antioxidant machinery. The simultaneous exposure to both stressors resulted in effects that were not the simple addition of the effects of both stressors taken separately. At the antioxidant level, the response to both stressors was like the response to metals alone. While this should have led to a reduction of frost tolerance, this was not observed. The impact of the simultaneous exposure to metals and cold acclimation on the transcriptome was unique, while at the proteomic level the cold acclimation component seemed to be dominant. Some genes and proteins displayed positive interaction patterns. These genes and proteins were related to the mitigation and reparation of oxidative damage, sugar catabolism, and the production of lignans, trehalose, and raffinose. Interestingly, none of these genes and proteins belonged to the traditional ROS homeostasis system. These results highlight the importance of the under-studied role of lignans and the ROS damage repair and removal system in plants simultaneously exposed to multiple stressors.

Integrated transcriptomics and proteomics analysis reveals muscle metabolism effects of dietary Ulva lactuca and ulvan lyase supplementation in weaned piglets.

Seaweeds, including the green Ulva lactuca, can potentially reduce competition between feed, food, and fuel. They can also contribute to the improved development of weaned piglets. However, their indigestible polysaccharides of the cell wall pose a challenge. This can be addressed through carbohydrase supplementation, such as the recombinant ulvan lyase. The objective of our study was to assess the muscle metabolism of weaned piglets fed with 7% U. lactuca and 0.01% ulvan lyase supplementation, using an integrated transcriptomics (RNA-seq) and proteomics (LC-MS) approach. Feeding piglets with seaweed and enzyme supplementation resulted in reduced macronutrient availability, leading to protein degradation through the proteasome (PSMD2), with resulting amino acids being utilized as an energy source (GOT2, IDH3B). Moreover, mineral element accumulation may have contributed to increased oxidative stress, evident from elevated levels of antioxidant proteins like catalase, as a response to maintaining tissue homeostasis. The upregulation of the gene AQP7, associated with the osmotic stress response, further supports these findings. Consequently, an increase in chaperone activity, including HSP90, was required to repair damaged proteins. Our results suggest that enzymatic supplementation may exacerbate the effects observed from feeding U. lactuca alone, potentially due to side effects of cell wall degradation during digestion.

Global Streptococcus pyogenes strain diversity, disease associations, and implications for vaccine development: a systematic review.

The high strain diversity of Streptococcus pyogenes serves as a major obstacle to vaccine development against this leading global pathogen. We did a systematic review of studies in PubMed, MEDLINE, and Embase that reported the global distribution of S pyogenes emm-types and emm-clusters from Jan 1, 1990, to Feb 23, 2023. 212 datasets were included from 55 countries, encompassing 74 468 bacterial isolates belonging to 211 emm-types. Globally, an inverse correlation was observed between strain diversity and the UNDP Human Development Index (HDI; r=-0·72; p<0·0001), which remained consistent upon subanalysis by global region and site of infection. Greater strain diversity was associated with a lower HDI, suggesting the role of social determinants in diseases caused by S pyogenes. We used a population-weighted analysis to adjust for the disproportionate number of epidemiological studies from high-income countries and identified 15 key representative isolates as vaccine targets. Strong strain type associations were observed between the site of infection (invasive, skin, and throat) and several streptococcal lineages. In conclusion, the development of a truly global vaccine to reduce the immense burden of diseases caused by S pyogenes should consider the multidimensional diversity of the pathogen, including its social and environmental context, and not merely its geographical distribution.

Enhanced ileum function in weaned piglets via Laminaria digitata and alginate lyase dietary inclusion: A combined proteomics and metabolomics analysis.

Laminaria digitata, a brown seaweed with prebiotic properties, can potentially enhance the resilience of weaned piglets to nutritional distress. However, their cell wall polysaccharides elude digestion by monogastric animals' endogenous enzymes. In vitro studies suggest alginate lyase's ability to degrade such polysaccharides. This study aimed to assess the impact of a 10% dietary inclusion of L. digitata and alginate lyase supplementation on the ileum proteome and metabolome, adopting a hypothesis-generating approach. Findings indicated that control piglets escalated glucose usage as an enteric energy source, as evidenced by the increased abundance of PKLR and PCK2 proteins and decreased tissue glucose concentration. Additionally, the inclusion of seaweed fostered a rise in proteins linked to enhanced enterocyte structural integrity (ACTBL2, CRMP1, FLII, EML2 and MYLK), elevated peptidase activity (NAALADL1 and CAPNS1), and heightened anti-inflammatory activity (C3), underscoring improved intestinal function. In addition, seaweed-fed piglets showed a reduced abundance of proteins related to apoptosis (ERN2) and proteolysis (DPP4). Alginate lyase supplementation appeared to amplify the initial effects of seaweed-only feeding, by boosting the number of differential proteins within the same pathways. This amplification is potentially due to increased intracellular nutrient availability, making a compelling case for further exploration of this dietary approach. SIGNIFICANCE: Pig production used to rely heavily on antibiotics and zinc oxide to deal with post-weaning stress in a cost-effective way. Their negative repercussions on public health and the environment have motivated heavy restrictions, and a consequent search for alternative feed ingredients/supplements. One of such alternatives is Laminaria digitata, a brown seaweed whose prebiotic components that can help weaned piglets deal with nutritional stress, by improving their gut health and immune status. However, their recalcitrant cell walls have antinutritional properties, for which alginate lyase supplementation is a possible solution. By evaluating ileal metabolism as influenced by dietary seaweed and enzyme supplementation, we aim at discovering how the weaned piglet adapts to them and what are their effects on this important segment of the digestive system.

Deep into the Apoplast: Grapevine and Plasmopara viticola Proteomes Reveal the Secret Beneath Host and Pathogen Communication at 6 h After Contact.

The apoplast is the first hub of plant-pathogen communication where pathogen effectors are recognized by plant defensive proteins and cell receptors, thus activating signal transduction pathways. As a result of this first contact, the host triggers a defense response that involves the modulation of extra- and intracellular proteins. In grapevine-pathogen interactions, little is known about the trafficking between extra- and intracellular spaces. Grapevine is an economically important crop that relies on heavy fungicide use to control several diseases, and a deeper knowledge on the activation of its immune response is crucial to define new control strategies. In this study, we focused on the first 6 h postinoculation with Plasmopara viticola to evaluate grapevine proteome modulation in the apoplast. The in planta P. viticola proteome was also assessed to enable a deeper understanding of plant-pathogen communication. Our results showed that several plant mechanisms are triggered in the tolerant grapevine cultivar Regent after inoculation, such as oomycete recognition, plant cell wall modifications, reactive oxygen species signaling, and secretion of proteins to disrupt oomycete structures. On the other hand, P. viticola proteins related to development and virulence were the most predominant. This pioneer study highlights the early dynamics of cellular communication in grapevine defense that leads to the successful establishment of an incompatible interaction.

A molecular study of Italian ryegrass grown on Martian regolith simulant.

In the last decade, the exploration of deep space has become the objective of the national space programs of many countries. The International Space Exploration Coordination Group has set a roadmap whose long-range strategy envisions the expansion of human presence in the solar system to progress with exploration and knowledge and to accelerate innovation. Crewed missions to Mars could be envisaged by 2040. In this scenario, finding ways to use the local resources for the provision of food, construction materials, propellants, pharmaceuticals is needed. Plants are important resources for deep space manned missions because they produce phytochemicals of pharmaceutical relevance, are sources of food and provide oxygen which is crucial in bioregenerative life support systems. Growth analysis and plant biomass yield have been previously evaluated on Martian regolith simulants; however, molecular approaches employing gene expression analysis and proteomics are still missing. The present work aims at filling this gap by providing molecular data on a representative member of the Poaceae, Lolium multiflorum Lam., grown on potting soil and a Martian regolith simulant (MMS-1). The molecular data were complemented with optical microscopy of root/leaf tissues and physico-chemical analyses. The results show that the plants grew for 2 weeks on regolith simulants. The leaves were bent downwards and chlorotic, the roots developed a lacunar aerenchyma and small brownish deposits containing Fe were observed. Gene expression analysis and proteomics revealed changes in transcripts related to the phenylpropanoid pathway, stress response, primary metabolism and proteins involved in translation and DNA methylation. Additionally, the growth of plants slightly but significantly modified the pH of the regolith simulants. The results here presented constitute a useful resource to get a comprehensive understanding of the major factors impacting the growth of plants on MMS-1.

An in-planta comparative study of Plasmopara viticola proteome reveals different infection strategies towards susceptible and Rpv3-mediated resistance hosts.

Plasmopara viticola, an obligate biotrophic oomycete, is the causal agent of one of the most harmful grapevine diseases, downy mildew. Within this pathosystem, much information is gathered on the host, as characterization of pathogenicity and infection strategy of a biotrophic pathogen is quite challenging. Molecular insights into P. viticola development and pathogenicity are just beginning to be uncovered, mainly by transcriptomic studies. Plasmopara viticola proteome and secretome were only predicted based on transcriptome data. In this study, we have identified the in-planta proteome of P. viticola during infection of a susceptible ('Trincadeira') and a Rpv3-mediated resistance ('Regent') grapevine cultivar. Four hundred and twenty P. viticola proteins were identified on a label-free mass spectrometry-based approach of the apoplastic fluid of grapevine leaves. Overall, our study suggests that, in the compatible interaction, P. viticola manipulates salicylic-acid pathway and isoprenoid biosynthesis to enhance plant colonization. Furthermore, during the incompatible interaction, development-associated proteins increased while oxidoreductases protect P. viticola from ROS-associated plant defence mechanism. Up to our knowledge this is the first in-planta proteome characterization of this biotrophic pathogen, thus this study will open new insights into our understanding of this pathogen colonization strategy of both susceptible and Rpv3-mediated resistance grapevine genotypes.

Trial of Deferiprone in Parkinson's Disease.

BACKGROUND: Iron content is increased in the substantia nigra of persons with Parkinson's disease and may contribute to the pathophysiology of the disorder. Early research suggests that the iron chelator deferiprone can reduce nigrostriatal iron content in persons with Parkinson's disease, but its effects on disease progression are unclear. METHODS: We conducted a multicenter, phase 2, randomized, double-blind trial involving participants with newly diagnosed Parkinson's disease who had never received levodopa. Participants were assigned (in a 1:1 ratio) to receive oral deferiprone at a dose of 15 mg per kilogram of body weight twice daily or matched placebo for 36 weeks. Dopaminergic therapy was withheld unless deemed necessary for symptom control. The primary outcome was the change in the total score on the Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS; range, 0 to 260, with higher scores indicating more severe impairment) at 36 weeks. Secondary and exploratory clinical outcomes at up to 40 weeks included measures of motor and nonmotor disability. Brain iron content measured with the use of magnetic resonance imaging was also an exploratory outcome. RESULTS: A total of 372 participants were enrolled; 186 were assigned to receive deferiprone and 186 to receive placebo. Progression of symptoms led to the initiation of dopaminergic therapy in 22.0% of the participants in the deferiprone group and 2.7% of those in the placebo group. The mean MDS-UPDRS total score at baseline was 34.3 in the deferiprone group and 33.2 in the placebo group and increased (worsened) by 15.6 points and 6.3 points, respectively (difference, 9.3 points; 95% confidence interval, 6.3 to 12.2; P<0.001). Nigrostriatal iron content decreased more in the deferiprone group than in the placebo group. The main serious adverse events with deferiprone were agranulocytosis in 2 participants and neutropenia in 3 participants. CONCLUSIONS: In participants with early Parkinson's disease who had never received levodopa and in whom treatment with dopaminergic medications was not planned, deferiprone was associated with worse scores in measures of parkinsonism than those with placebo over a period of 36 weeks. (Funded by the European Union Horizon 2020 program; FAIRPARK-II ClinicalTrials.gov number, NCT02655315.).

Platelet-Rich Plasma, an Innovative and Noninvasive Technique for Closure of Tracheoesophageal Fistula After Laryngectomy, Report of 2 Cases.

An innovative and noninvasive technique for closure of persistent tracheoesophageal fistula after total laryngectomy is described. In our preliminary study, two patients were included. No clinical and radiological signs of locoregional recurrence prior to treatment were diagnosed. We performed local injections of autologous platelet-rich plasma (PRP) according to our protocol. Complete closure of the fistula was observed in both patients who were able to take normal feeding. No side effects associated with the procedure were observed. These preliminary results are encouraging to consider PRP injection before more invasive surgical techniques in the treatment of persistent tracheoesophageal fistulas after total laryngectomy.

Untargeted Metabolomics Sheds Light on the Secondary Metabolism of Fungi Triggered by Choline-Based Ionic Liquids.

Fungal secondary metabolites constitute a rich source of yet undiscovered bioactive compounds. Their production is often silent under standard laboratory conditions, but the production of some compounds can be triggered simply by altering the cultivation conditions. The usage of an organic salt - ionic liquid - as growth medium supplement can greatly impact the biosynthesis of secondary metabolites, leading to higher diversity of compounds accumulating extracellularly. This study examines if such supplements, specifically cholinium-based ionic liquids, can support the discovery of bioactive secondary metabolites across three model species: Neurospora crassa, Aspergillus nidulans, and Aspergillus fumigatus. Enriched organic extracts obtained from medium supernatant revealed high diversity in metabolites. The supplementation led apparently to increased levels of either 1-aminocyclopropane-1-carboxylate or α-aminoisobutyric acid. The extracts where bioactive against two major foodborne bacterial strains: Staphylococcus aureus and Escherichia coli. In particular, those retrieved from N. crassa cultures showed greater bactericidal potential compared to control extracts derived from non-supplemented cultures. An untargeted mass spectrometry analysis using the Global Natural Product Social Molecular Networking tool enabled to capture the chemical diversity driven by the ionic liquid stimuli. Diverse macrolides, among other compounds, were putatively associated with A. fumigatus; whereas an unexpected richness of cyclic (depsi)peptides with N. crassa. Further studies are required to understand if the identified peptides are the major players of the bioactivity of N. crassa extracts, and to decode their biosynthesis pathways as well.

Proteomics Evidence of a Systemic Response to Desiccation in the Resurrection Plant Haberlea rhodopensis.

Global warming and drought stress are expected to have a negative impact on agricultural productivity. Desiccation-tolerant species, which are able to tolerate the almost complete desiccation of their vegetative tissues, are appropriate models to study extreme drought tolerance and identify novel approaches to improve the resistance of crops to drought stress. In the present study, to better understand what makes resurrection plants extremely tolerant to drought, we performed transmission electron microscopy and integrative large-scale proteomics, including organellar and phosphorylation proteomics, and combined these investigations with previously published transcriptomic and metabolomics data from the resurrection plant Haberlea rhodopensis. The results revealed new evidence about organelle and cell preservation, posttranscriptional and posttranslational regulation, photosynthesis, primary metabolism, autophagy, and cell death in response to desiccation in H. rhodopensis. Different protective intrinsically disordered proteins, such as late embryogenesis abundant (LEA) proteins, thaumatin-like proteins (TLPs), and heat shock proteins (HSPs), were detected. We also found a constitutively abundant dehydrin in H. rhodopensis whose phosphorylation levels increased under stress in the chloroplast fraction. This integrative multi-omics analysis revealed a systemic response to desiccation in H. rhodopensis and certain targets for further genomic and evolutionary studies on DT mechanisms and genetic engineering towards the improvement of drought tolerance in crops.

Identification of Novel Candidate Genes Involved in Apple Cuticle Integrity and Russeting-Associated Triterpene Synthesis Using Metabolomic, Proteomic, and Transcriptomic Data.

Apple russeting develops on the fruit surface when skin integrity has been lost. It induces a modification of fruit wax composition, including its triterpene profile. In the present work, we studied two closely related apple varieties, 'Reinette grise du Canada' and 'Reinette blanche du Canada', which display russeted and non-russeted skin phenotypes, respectively, during fruit development. To better understand the molecular events associated with russeting and the differential triterpene composition, metabolomics data were generated using liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS) and combined with proteomic and transcriptomic data. Our results indicated lower expression of genes linked to cuticle biosynthesis (cutin and wax) in russet apple throughout fruit development, along with an alteration of the specialized metabolism pathways, including triterpene and phenylpropanoid. We identified a lipid transfer protein (LTP3) as a novel player in cuticle formation, possibly involved in the transport of both cutin and wax components in apple skin. Metabolomic data highlighted for the first time a large diversity of triterpene-hydroxycinnamates in russeted tissues, accumulation of which was highly correlated with suberin-related genes, including some enzymes belonging to the BAHD (HXXXD-motif) acyltransferase family. Overall, this study increases our understanding about the crosstalk between triterpene and suberin pathways.

Interest of a Joint Use of Two Diagnostic Tools of Burnout: Comparison between the Oldenburg Burnout Inventory and the Early Detection Tool of Burnout Completed by Physicians.

Most research on burnout is based on self-reported questionnaires. Nevertheless, as far as the clinical judgement is concerned, a lack of consensus about burnout diagnosis constitutes a risk of misdiagnosis. Hence, this study aims to assess the added value of a joint use of two tools and compare their diagnostic accuracy: (1) the early detection tool of burnout, a structured interview guide, and (2) the Oldenburg burnout inventory, a self-reported questionnaire. The interview guide was tested in 2019 by general practitioners and occupational physicians among 123 Belgian patients, who also completed the self-reported questionnaire. A receiver operating characteristic curve analysis allowed the identification of a cut-off score for the self-reported questionnaire. Diagnostic accuracy was then contrasted by a McNemar chi-squared test. The interview guide has a significantly higher sensitivity (0.76) than the self-reported questionnaire (0.70), even by comparing the self-reported questionnaires with the interviews of general practitioners and occupational physicians separately. However, both tools have a similar specificity (respectively, 0.60-0.67), except for the occupational physicians' interviews, where the specificity (0.68) was significantly lower than the self-reported questionnaire (0.70). In conclusion, the early detection tool of burnout is more sensitive than the Oldenburg burnout inventory, but seems less specific. However, by crossing diagnoses reported by patients and by physicians, they both seem useful to support burnout diagnosis.

The Cell Wall Proteome of Craterostigma plantagineum Cell Cultures Habituated to Dichlobenil and Isoxaben.

The remarkable desiccation tolerance of the vegetative tissues in the resurrection species Craterostigma plantagineum (Hochst.) is favored by its unique cell wall folding mechanism that allows the ordered and reversible shrinking of the cells without damaging neither the cell wall nor the underlying plasma membrane. The ability to withstand extreme drought is also maintained in abscisic acid pre-treated calli, which can be cultured both on solid and in liquid culture media. Cell wall research has greatly advanced, thanks to the use of inhibitors affecting the biosynthesis of e.g., cellulose, since they allowed the identification of the compensatory mechanisms underlying habituation. Considering the innate cell wall plasticity of C. plantagineum, the goal of this investigation was to understand whether habituation to the cellulose biosynthesis inhibitors dichlobenil and isoxaben entailed or not identical mechanisms as known for non-resurrection species and to decipher the cell wall proteome of habituated cells. The results showed that exposure of C. plantagineum calli/cells triggered abnormal phenotypes, as reported in non-resurrection species. Additionally, the data demonstrated that it was possible to habituate Craterostigma cells to dichlobenil and isoxaben and that gene expression and protein abundance did not follow the same trend. Shotgun and gel-based proteomics revealed a common set of proteins induced upon habituation, but also identified candidates solely induced by habituation to one of the two inhibitors. Finally, it is hypothesized that alterations in auxin levels are responsible for the increased abundance of cell wall-related proteins upon habituation.

Validity and Reliability of the French Short Version of the Questionnaire of Olfactory Disorders-Negative Statements (sQOD-NS).

OBJECTIVE: To develop a French Short Version of the Questionnaire of Olfactory Disorders-Negative Statements (Fr-sQOD) to assess the quality of life impairments of patients with olfactory dysfunction (OD). METHODS: Patients with OD and controls were enrolled from 2 academic centers. Individuals completed the Fr-sQOD, an OD visual analog scale severity, and the French version of the sinonasal outcome tool-22 (SNOT-22). Cronbach α was used to measure the internal consistency of Fr-sQOD. The reliability and the external validity of Fr-sQOD were assessed through a test-retest approach and by correlating Fr-sQOD with SNOT-22 scores, respectively. The external validity was assessed by correlation analysis between Fr-sQOD and the result of an assessment of the severity of OD on a visual analog scale. RESULTS: Eighty patients completed the evaluations. The internal consistency was adequate (Cronbach α .96), and the test-retest reliability was high in the entire cohort (rs = 0.877, P < .001). The correlation between Fr-sQOD total scores and the severity of OD was moderate but significant (rs = -0.431; P = .001) supporting an acceptable external validity. Patients with OD had a significantly higher score of Fr-sQOD than healthy individuals (P < .001), indicating a high internal validity. CONCLUSION: The Fr-sQOD is a reliable and valid self-administered tool in the evaluation of the impact of OD on quality of life of French-speaking patients.

Tobacco use and related behaviors among staff and students in a university hospital: A large cross-sectional survey.

INTRODUCTION: Smoking prevalence in the overall population in France was 27% in 2017. There are few data about smoking prevalence in hospital workers. The aim of this study was to assess prevalence of current smoking in student and staff populations at Lyon University Hospital. Secondary objectives were to identify main variables associated with current smoking and willingness to quit. METHODS: We designed a single center, cross-sectional survey, using printed questionnaires. During one day, all registered staff and students were surveyed. We used optical reading to extract information from questionnaires. We performed univariate and multivariate analysis adjusted on most relevant factors. RESULTS: We analyzed 9712 questionnaires. The participating rates were high: 40.6% in the student cohort and 51.5% in the staff cohort. The proportion of current cigarette users was 26% in students and 25% in staff. In multivariate analysis, current smoking was significantly associated with: younger age, male sex, occupation type (e.g. logistical staff, and paramedical students), overnight work, and e-cigarette use. Among smokers, 53% reported a willingness to quit. In multivariate analysis, number of quit attempts, and feeling symptoms from tobacco were associated with willingness to quit. CONCLUSIONS: Current smoking is less frequent in our cohorts of hospital staff and students than in the general French population. However, there are deep disparities in current smoking prevalence underlining a heterogeneous population. Among smokers, the majority reported a willingness to quit and some predictive factors may help to target this audience.

Stress response of lettuce (Lactuca sativa) to environmental contamination with selected pharmaceuticals: A proteomic study.

Pharmaceutical compounds have been found in rivers and treated wastewaters. They often contaminate irrigation waters and consequently accumulate in edible vegetables, causing changes in plants metabolism. The main objective of this work is to understand how lettuce plants cope with the contamination from three selected pharmaceuticals using a label free proteomic analysis. A lettuce hydroponic culture, grown for 36 days, was exposed to metformin, acetaminophen and carbamazepine (at 1 mg/L), during 8 days, after which roots and leaves were sampled and analysed using a liquid chromatography-mass spectrometry proteomics-based approach. In roots, a total of 612 proteins showed differentially accumulation while in leaves 237 proteins were identified with significant differences over controls. Carbamazepine was the contaminant that most affected protein abundance in roots, while in leaves the highest number of differentially accumulated proteins was observed for acetaminophen. In roots under carbamazepine, stress related protein species such as catalase, superoxide dismutase and peroxidases presented higher abundance. Ascorbate peroxidase increased in roots under metformin. Cell respiration protein species were affected by the presence of the three pharmaceuticals suggesting possible dysregulation of the Krebs cycle. Acetaminophen caused the main differences in respiration pathways, with more emphasis in leaves. Lettuce plants revealed different tolerance levels when contaminants were compared, being more tolerant to metformin presence and less tolerant to carbamazepine. SIGNIFICANCE: The significant increase of emerging contaminants in ecosystems makes essential to understand how these compounds may affect the metabolism of different organisms. Our study contributes with a detailed approach of the main interactions that may occur in plant metabolism when subjected to the stress induced by three different pharmaceuticals (acetaminophen, carbamazepine and metformin).

Plant Extracellular Vesicles and Nanovesicles: Focus on Secondary Metabolites, Proteins and Lipids with Perspectives on Their Potential and Sources.

While human extracellular vesicles (EVs) have attracted a big deal of interest and have been extensively characterized over the last years, plant-derived EVs and nanovesicles have earned less attention and have remained poorly investigated. Although a series of investigations already revealed promising beneficial health effects and drug delivery properties, adequate (pre)clinical studies are rare. This fact might be caused by a lack of sources with appropriate qualities. Our study introduces plant cell suspension culture as a new and well controllable source for plant EVs. Plant cells, cultured in vitro, release EVs into the growth medium which could be harvested for pharmaceutical applications. In this investigation we characterized EVs and nanovesicles from distinct sources. Our findings regarding secondary metabolites indicate that these might not be packaged into EVs in an active manner but enriched in the membrane when lipophilic enough, since apparently lipophilic compounds were associated with nanovesicles while more hydrophilic structures were not consistently found. In addition, protein identification revealed a possible explanation for the mechanism of EV cell wall passage in plants, since cell wall hydrolases like 1,3-ß-glucosidases, pectinesterases, polygalacturonases, ß-galactosidases and ß-xylosidase/α-L-arabinofuranosidase 2-like are present in plant EVs and nanovesicles which might facilitate cell wall transition. Further on, the identified proteins indicate that plant cells secrete EVs using similar mechanisms as animal cells to release exosomes and microvesicles.

Molecular insights into plant desiccation tolerance: transcriptomics, proteomics and targeted metabolite profiling in Craterostigma plantagineum.

The resurrection plant Craterostigma plantagineum possesses an extraordinary capacity to survive long-term desiccation. To enhance our understanding of this phenomenon, complementary transcriptome, soluble proteome and targeted metabolite profiling was carried out on leaves collected from different stages during a dehydration and rehydration cycle. A total of 7348 contigs, 611 proteins and 39 metabolites were differentially abundant across the different sampling points. Dynamic changes in transcript, protein and metabolite levels revealed a unique signature characterizing each stage. An overall low correlation between transcript and protein abundance suggests a prominent role for post-transcriptional modification in metabolic reprogramming to prepare plants for desiccation and recovery. The integrative analysis of all three data sets was performed with an emphasis on photosynthesis, photorespiration, energy metabolism and amino acid metabolism. The results revealed a set of precise changes that modulate primary metabolism to confer plasticity to metabolic pathways, thus optimizing plant performance under stress. The maintenance of cyclic electron flow and photorespiration, and the switch from C3 to crassulacean acid metabolism photosynthesis, may contribute to partially sustain photosynthesis and minimize oxidative damage during dehydration. Transcripts with a delayed translation, ATP-independent bypasses, alternative respiratory pathway and 4-aminobutyric acid shunt may all play a role in energy management, together conferring bioenergetic advantages to meet energy demands upon rehydration. This study provides a high-resolution map of the changes occurring in primary metabolism during dehydration and rehydration and enriches our understanding of the molecular mechanisms underpinning plant desiccation tolerance. The data sets provided here will ultimately inspire biotechnological strategies for drought tolerance improvement in crops.

An apoplastic fluid extraction method for the characterization of grapevine leaves proteome and metabolome from a single sample.

The analysis of complex biological systems keeps challenging researchers. The main goal of systems biology is to decipher interactions within cells, by integrating datasets from large scale analytical approaches including transcriptomics, proteomics and metabolomics and more specialized 'OMICS' such as epigenomics and lipidomics. Studying different cellular compartments allows a broader understanding of cell dynamics. Plant apoplast, the cellular compartment external to the plasma membrane including the cell wall, is particularly demanding to analyze. Despite our knowledge on apoplast involvement on several processes from cell growth to stress responses, its dynamics is still poorly known due to the lack of efficient extraction processes adequate to each plant system. Analyzing woody plants such as grapevine raises even more challenges. Grapevine is among the most important fruit crops worldwide and a wider characterization of its apoplast is essential for a deeper understanding of its physiology and cellular mechanisms. Here, we describe, for the first time, a vacuum-infiltration-centrifugation method that allows a simultaneous extraction of grapevine apoplastic proteins and metabolites from leaves on a single sample, compatible with high-throughput mass spectrometry analyses. The extracted apoplast from two grapevine cultivars, Vitis vinifera cv 'Trincadeira' and 'Regent', was directly used for proteomics and metabolomics analysis. The proteome was analyzed by nanoLC-MS/MS and more than 700 common proteins were identified, with highly diverse biological functions. The metabolome profile through FT-ICR-MS allowed the identification of 514 unique putative compounds revealing a broad spectrum of molecular classes.