The different response of Brassica napus genotypes to microspore embryogenesis induced by heat shock and trichostatin A is not determined by changes in cell wall structure and composition but by different stress tolerance.

During microspore embryogenesis, microspores are induced to develop into haploid embryos. In Brassica napus, microspore embryogenesis is induced by a heat shock (HS), which initially produces embryogenic structures with different cell wall architectures and compositions, and with different potentials to develop into embryos. The B. napus DH4079 and DH12075 genotypes have high and very low embryo yields, respectively. In DH12075, embryo yield is greatly increased by combining HS and the histone deacetylase (HDAC) inhibitor trichostatin A (TSA). However, we show that HS + TSA inhibits embryogenesis in the highly embryogenic DH4079 line. To ascertain why TSA has such different effects in these lines, we treated DH4079 and DH12075 microspore cultures with TSA and compared the cell wall structure and composition of the different embryogenic structures in both lines, specifically the in situ levels and distribution of callose, cellulose, arabinogalactan proteins and high and low methyl-esterified pectin. For both lines, HS + TSA led to the formation of cell walls unfavorable for embryogenesis progression, with reduced levels of arabinogalactan proteins, reduced cell adhesion of inner walls and altered pectin composition. Thus, TSA effects on cell walls cannot explain their different embryogenic response to TSA. We also applied TSA to DH4079 cultures at different times and concentrations before HS application, with no negative effects on embryogenic induction. These results indicate that DH4079 microspores are hypersensitive to combined TSA and HS treatments, and open up new hypotheses about the causes of such hypersensitivity.

Iron therapy supplementation in inflammatory bowel disease patients with iron deficiency anemia: findings from a real-world analysis in Italy.

BACKGROUND: This real-world analysis evaluated iron therapy supplementation in inflammatory bowel disease patients with iron-deficiency anemia, considering disease progression and healthcare resource consumption. METHODS: A retrospective observational study was conducted using administrative databases of a pool of Italian healthcare entities, covering about 9.3 million beneficiaries. Between January 2010 and September 2017, adult patients were enrolled in the presence of either hospitalization or active exemption code for ulcerative colitis/Crohn's disease, or one vedolizumab prescription. Iron-deficiency anemia was identified by at least one prescription for iron and/or hospitalization for iron-deficiency anemia and/or blood transfusion (proxy of diagnosis). Patients were divided in untreated and iron-treated during 12-month follow-up and analyzed before and after propensity score matching. Disease progression, was evaluated through inflammatory bowel disease-related hospitalizations and surgeries, and healthcare resource utilization was assessed. RESULTS: Overall, 1753 patients were included, 1077 (61.4%) treated with iron therapy and 676 (38.6%) untreated. After propensity score matching, 655 patients were included in each group. In unbalanced cohorts, disease progression was significantly reduced in patients receiving iron therapy compared to the untreated (11.0% vs. 15.7%, P  < 0.01), and this trend was maintained also after applying propensity score matching. The overall mean cost/patient was significantly lower in iron-treated than untreated (4643€ vs. 6391€, P  < 0.01). CONCLUSION: The findings of this real-world analysis suggest that iron therapy was associated with significant benefits in inflammatory bowel disease patients with iron-deficiency anemia, in terms of both disease progression and healthcare resource utilization.

The Highly Embryogenic Brassica napus DH4079 Line Is Recalcitrant to Agrobacterium-Mediated Genetic Transformation.

Brassica napus is a species of high agronomic interest, used as a model to study different processes, including microspore embryogenesis. The DH4079 and DH12075 lines show high and low embryogenic response, respectively, which makes them ideal to study the basic mechanisms controlling embryogenesis induction. Therefore, the availability of protocols for genetic transformation of these two backgrounds would help to generate tools to better understand this process. There are some reports in the literature showing the stable transformation of DH12075. However, no equivalent studies in DH4079 have been reported to date. We explored the ability of DH4079 plants to be genetically transformed. As a reference to compare with, we used the same protocols to transform DH12075. We used three different protocols previously reported as successful for B. napus stable transformation with Agrobacterium tumefaciens and analyzed the response of plants. Whereas DH12075 plants responded to genetic transformation, DH4079 plants were completely recalcitrant, not producing any single regenerant out of the 1784 explants transformed and cultured. Additionally, an Agrobacterium rhizogenes transient transformation assay was performed on both lines, and only DH12075, but no DH4079 seedlings, responded to A. rhizogenes infection. Therefore, we propose that the DH4079 line is recalcitrant to Agrobacterium-mediated transformation.

Iron deficiency anemia impacts disease progression and healthcare resource consumption in patients with inflammatory bowel disease: a real-world evidence study.

Background: Iron deficiency anemia (IDA) is a common extraintestinal manifestation of inflammatory bowel disease (IBD), affecting around one-third of patients. Objective: To compare IBD progression and healthcare resource utilization in patients with and without a co-diagnosis of IDA in a real-world setting. Design: A retrospective comparative study was conducted using Italian entities' administrative databases, covering 9.3 million health-assisted individuals. Methods: Adult IBD patients diagnosed with ulcerative colitis and/or Crohn's disease were enrolled between January 2010 and September 2017. Within 12 months from IBD diagnosis, IDA was identified by at least one prescription for iron and/or IDA hospitalization and/or blood transfusion (proxy of diagnosis). IBD population was divided according to the presence/absence of IDA. Given the nonrandom patients' allocation, propensity score matching (PSM) was applied to abate potential unbalances between the groups. Before and after PSM, IBD progression (in terms of IBD-related hospitalizations and surgeries), and healthcare resource costs were assessed. Results: Overall, 13,475 IBD patients were included, with an average age at diagnosis of 49.9 years, and a 53.9% percentage of male gender. Before PSM, 1753 (13%) patients were IBD-IDA, and 11,722 (87%) were IBD-non-IDA. Post-PSM, 1753 IBD-IDA patients were matched with 3506 IBD-non-IDA. Before PSM, IBD progression was significantly higher in IBD-IDA (12.8%) than in IBD-non-IDA (6.5%) (p < 0.001). After PSM, IBD progression and IBD-related hospitalizations were significantly (p < 0.001) more frequent in IBD-IDA patients (12.8% and 12.0%, respectively) compared to IBD-non-IDA (8.7% and 7.7%). Consistently, healthcare expenditures resulted significantly higher among IDA patients (p < 0.001), with an overall mean annual cost of €5317 compared to €2798 for patients without IDA. These results were confirmed after PSM matching, as the mean annual total cost/patient in IBD-IDA versus IBD-non-IDA were €3693 and €3046, respectively (p < 0.001). Conclusion: In a real-life setting, IDA co-diagnosis in IBD patients was associated with disease progression and higher related economic burden.

Calcium dynamics and modulation in carrot somatic embryogenesis.

Free calcium (Ca2+) is a pivotal player in different in vivo and in vitro morphogenic processes. In the induction of somatic embryogenesis, its role has been demonstrated in different species. In carrot, however, this role has been more controversial. In this work, we developed carrot lines expressing cameleon Ca2+ sensors. With them, Ca2+ levels and distribution in the different embryogenic structures formed during the induction and development of somatic embryos were analyzed by FRET. We also used different chemicals to modulate intracellular Ca2+ levels (CaCl2, ionophore A23187, EGTA), to inhibit calmodulin (W-7) and to inhibit callose synthesis (2-deoxy-D-glucose) at different times, principally during the first stages of embryo induction. Our results showed that high Ca2+ levels and the development of a callose layer are markers of cells induced to embryogenesis, which are the precursors of somatic embryos. Disorganized calli and embryogenic masses have different Ca2+ patterns associated to their embryogenic competence, with higher levels in embryogenic cells than in callus cells. The efficiency of somatic embryogenesis in carrot can be effectively modulated by allowing, within a range, more Ca2+ to enter the cell to act as a second messenger to trigger embryogenesis induction. Once induced, Ca2+-calmodulin signaling seems related with the transcriptional remodeling needed for embryo progression, and alterations of Ca2+ or calmodulin levels negatively affect the efficiency of the process.

Calcium Dynamics, WUSCHEL Expression and Callose Deposition during Somatic Embryogenesis in Arabidopsis thaliana Immature Zygotic Embryos.

In this work, we studied the induction of somatic embryogenesis in Arabidopsis using IZEs as explants. We characterized the process at the light and scanning electron microscope level and studied several specific aspects such as WUS expression, callose deposition, and principally Ca2+ dynamics during the first stages of the process of embryogenesis induction, by confocal FRET analysis with an Arabidopsis line expressing a cameleon calcium sensor. We also performed a pharmacological study with a series of chemicals know to alter calcium homeostasis (CaCl2, inositol 1,4,5-trisphosphate, ionophore A23187, EGTA), the calcium-calmodulin interaction (chlorpromazine, W-7), and callose deposition (2-deoxy-D-glucose). We showed that, after determination of the cotiledonary protrusions as embryogenic regions, a finger-like appendix may emerge from the shoot apical region and somatic embryos are produced from the WUS-expressing cells of the appendix tip. Ca2+ levels increase and callose is deposited in the cells of the regions where somatic embryos will be formed, thereby constituting early markers of the embryogenic regions. We also found that Ca2+ homeostasis in this system is strictly maintained and cannot be altered to modulate embryo production, as shown for other systems. Together, these results contribute to a better knowledge and understanding of the process of induction of somatic embryos in this system.

The Influence of Iron-Deficiency Anaemia (IDA) Therapy on Clinical Outcomes and Healthcare Resource Consumptions in Chronic Kidney Disease Patients Affected by IDA: A Real-Word Evidence Study among the Italian Population.

Anaemia is a uraemia-related complication frequently found in non-dialysis-dependent chronic kidney disease (ND-CKD) patients, with iron-deficiency anaemia (IDA) as the main underlying mechanism. Given the suboptimal anaemia management in ND-CKD patients with a co-diagnosis of IDA, this study evaluated the role of IDA therapy on clinical outcomes and healthcare resource consumptions in an Italian clinical setting. A retrospective observational real-world analysis was performed on administrative databases of healthcare entities, covering around 6.9 million health-assisted individuals. From January 2010 to March 2019, ND-CKD patients were included and diagnosed with IDA in the presence of two low-haemoglobin (Hb) measurements. Patients were divided into IDA-treated and untreated, based on the prescription of iron [Anatomical-Therapeutic Chemical (ATC) code B03A] or anti-anaemia preparations (ATC code B03X), and evaluated during a 6-month follow-up from the index date [first low haemoglobin (Hb) detection]. IDA treatment resulted in significantly decreased incidence of all cause-related, cardiovascular-related, and IDA-related hospitalizations (treated vs. untreated: 44.5% vs. 81.8%, 12.3% vs. 25.3%, and 16.2% vs. 26.2%, respectively, p < 0.001). A healthcare direct cost estimation showed that overall mean expenditure per patient reduced by 47% with IDA treatment (5245€ vs. 9918€, p < 0.001), mainly attributable to hospitalizations (3767€ vs. 8486€, p < 0.001). This real-life analysis on Italian ND-CKD-IDA patients indicates that IDA therapy administration provides significant benefits in terms of patients' clinical outcomes and healthcare cost savings.

Doubled Haploids in Eggplant.

Eggplant is a solanaceous crop cultivated worldwide for its edible fruit. Eggplant breeding programs are mainly aimed to the generation of F1 hybrids by crossing two highly homozygous, pure lines, which are traditionally obtained upon several self crossing generations, which is an expensive and time consuming process. Alternatively, fully homozygous, doubled haploid (DH) individuals can be induced from haploid cells of the germ line in a single generation. Several attempts have been made to develop protocols to produce eggplant DHs principally using anther culture and isolated microspore culture. Eggplant could be considered a moderately recalcitrant species in terms of ability for DH production. Anther culture stands nowadays as the most valuable technology to obtain eggplant DHs. However, the theoretical possibility of having plants regenerated from somatic tissues of the anther walls cannot be ruled out. For this reason, the use of isolated microspores is recommended when possible. This approach still has room for improvement, but it is largely genotype-dependent. In this review, we compile the most relevant advances made in DH production in eggplant, their application to breeding programs, and the future perspectives for the development of other, less genotype-dependent, DH technologies.

Anther and Isolated Microspore Culture in Eggplant (Solanum melongena L.).

Eggplant is one of the five important, worldwide-distributed solanaceous crops. The use of anther culture technology to produce pure, 100% homozygous doubled haploid lines for hybrid seed production is possible since 1982, where the first protocol of wide application to different eggplant materials was published. From then on, different improvements and adaptations to different materials have been made. In parallel, protocols to implement isolated microspore culture technology in eggplant have been developed principally in the last decade, which opens the door for a more efficient DH production in this species. In this chapter, two protocols, one for anther and other for isolated microspore culture in eggplant, are described. Some steps and materials are common to both approaches. A detailed description of each step from is provided.

SWATH-MS Protocols in Human Diseases.

Identification of molecular biomarkers for human diseases is one of the most important disciplines in translational science as it helps to elucidate their origin and early progression. Thus, it is a key factor in better diagnosis, prognosis, and treatment. Proteomics can help to solve the problem of sample complexity when the most common primary sample specimens were analyzed: organic fluids of easy access. The latest developments in high-throughput and label-free quantitative proteomics (SWATH-MS), together with more advanced liquid chromatography, have enabled the analysis of large sample sets with the sensitivity and depth needed to succeed in this task. In this chapter, we show different sample processing methods (major protein depletion, digestion, etc.) and a micro LC-SWATH-MS protocol to identify/quantify several proteins in different types of samples (serum/plasma, saliva, urine, tears).

Anther Culture in Eggplant (Solanum melongena L.).

For a long time, conventional breeding methods have been used to obtain pure, 100% homozygous lines for hybrid seed production in crops of agronomic interest. However, by doubled haploid technology, it is possible to produce 100% homozygous plants derived from precursors of male gametophytes (androgenesis), to accelerate the production of pure lines, which implies important time and cost savings. In this chapter, a protocol for anther culture in eggplant is described, from donor plant growth conditions to regeneration and acclimation of doubled haploid plants, as well as a description of how to analyze ploidy levels of regenerated plants.

Insights into the function of NADPH thioredoxin reductase C (NTRC) based on identification of NTRC-interacting proteins in vivo.

Redox regulation in heterotrophic organisms relies on NADPH, thioredoxins (TRXs), and an NADPH-dependent TRX reductase (NTR). In contrast, chloroplasts harbor two redox systems, one that uses photoreduced ferredoxin (Fd), an Fd-dependent TRX reductase (FTR), and TRXs, which links redox regulation to light, and NTRC, which allows the use of NADPH for redox regulation. It has been shown that NTRC-dependent regulation of 2-Cys peroxiredoxin (PRX) is critical for optimal function of the photosynthetic apparatus. Thus, the objective of the present study was the analysis of the interaction of NTRC and 2-Cys PRX in vivo and the identification of proteins interacting with them with the aim of identifying chloroplast processes regulated by this redox system. To assess this objective, we generated Arabidopsis thaliana plants expressing either an NTRC-tandem affinity purification (TAP)-Tag or a green fluorescent protein (GFP)-TAP-Tag, which served as a negative control. The presence of 2-Cys PRX and NTRC in complexes isolated from NTRC-TAP-Tag-expressing plants confirmed the interaction of these proteins in vivo. The identification of proteins co-purified in these complexes by MS revealed the relevance of the NTRC-2-Cys PRX system in the redox regulation of multiple chloroplast processes. The interaction of NTRC with selected targets was confirmed in vivo by bimolecular fluorescence complementation (BiFC) assays.

Embryogenic competence of microspores is associated with their ability to form a callosic, osmoprotective subintinal layer.

Microspore embryogenesis is an experimental morphogenic pathway with important applications in basic research and applied plant breeding, but its genetic, cellular, and molecular bases are poorly understood. We applied a multidisciplinary approach using confocal and electron microscopy, detection of Ca2+, callose, and cellulose, treatments with caffeine, digitonin, and endosidin7, morphometry, qPCR, osmometry, and viability assays in order to study the dynamics of cell wall formation during embryogenesis induction in a high-response rapeseed (Brassica napus) line and two recalcitrant rapeseed and eggplant (Solanum melongena) lines. Formation of a callose-rich subintinal layer (SL) was common to microspore embryogenesis in the different genotypes. However, this process was directly related to embryogenic response, being greater in high-response genotypes. A link could be established between Ca2+ influx, abnormal callose/cellulose deposition, and the genotype-specific embryogenic competence. Callose deposition in inner walls and SLs are independent processes, regulated by different callose synthases. Viability and control of internal osmolality are also related to SL formation. In summary, we identified one of the causes of recalcitrance to embryogenesis induction: a reduced or absent protective SL. In responding genotypes, SLs are markers for changes in cell fate and serve as osmoprotective barriers to increase viability in imbalanced in vitro environments. Genotype-specific differences relate to different responses against abiotic (heat/osmotic) stresses.

Calidad de las historias clínicas elaborados por internos de medicina - UMSA La Paz 2017 / Quality of clinical records prepared by the medical interns - UMSA La Paz 2017

INTRODUCCIÓN: La actividad del interno de medicina, considera como una práctica pre profesional, desarrollada en un contexto "real", significando que los internos efectúan su capacitación con pacientes verdaderos. La elaboración de la Historia Clínica (H.Cl.) por lo tanto deberá contener la mejor información del paciente. OBJETIVO: dirigida a identificar la calidad de la elaboración de las H.Cl. por los internos de medicina de la UMSA. MATERIAL Y MÉTODO: El diseñó corresponde a una investigación cuantitativa, observacional, longitudinal y analítica. Metodológicamente se efectuó el seguimiento a 8 internos durante el año 2015, revisando las H.Cl. que elaboraban durante sus diferentes pasantías en las especialidades de Medicina, Pediatría, Cirugía, Ginecología - Obstetricia, constituyendo un total de 64 expedientes clínicos, 8 por interno. Para la evaluación de la calidad de las H. Cl. se utilizó una plantilla con cinco tópicos, cuya validación se desprendió del procedimiento empleado en las auditorías internas utilizadas en los hospitales. RESULTADOS Y DISCUSIÓN: Solo 19 H.Cl. lograron la categoría de aceptables (29,7 por ciento), frente a las otras dos categorías 15 H.Cl. fueron catalogadas como insuficientes (23,4 por ciento) el resto de las historias clínicas 30, adolecían de varios defectos que se las califico como inaceptables (46,9 por ciento). SE puede señalar que solo tres de diez H.Cl. fueron elaboradas apropiadamente, adicionalmente cerca de la mitad del total de los documentos fueron apuntadas como inaceptables, reflejando la las H.Cl. fueron elaboradas de manera impropia, catalogadas como de mala calidad CONCLUSIONES: La evaluación sobre la calidad de las H.Cl. permitió identificary poner de manifiesto la presencia de una brecha marcada entre el propósito ideal buscado por el plan de estudios de la carrera y el producto final como parte del proceso de profesionalización.

INTRODUCTION: The medical intern activity, considers as a pre-professional practice, developed in a "real" context, meaning that the interns carry out their training with real patients. The elaboration of the Clinical Record (H.Cl.) should therefore contain the best patient information. OBJECTIVE: aimed at identifying the quality of the elaboration ofH. Cl. by the medical interns of UMSA. MATERIAL AND METHOD: The design corresponds to a quantitative, observational, longitudinal and analytical investigation. Methodologically, 8 interns were monitored during 2015, reviewing the H.Cl. that they elaborated during their different internships in the specialties of Medicine, Pediatrics, Surgery, Gynecology - Obstetrics, constituting a total of 64 clinical files, 8 per intern. For the evaluation of the quality of the H.Cl. A template with five topics was used, whose validation was detached from the procedure used in the internal auditing used in the hospitals. RESULTS AND DISCUSSION: Only 19 H.Cl. achieved the category of acceptable (29.7 percent), compared to the other two categories 15 H.Cl. were classified as insufficient (23.4 percent) the rest of the clinical histories 30, suffered from several defects that were classifiedas unacceptable (46.9 percent). It can be noted that only three out of ten H.Cl. were elaborated appropriately, additionally close to half of the total of the documents were pointed out as unacceptable, reflecting the H.Cl. were improperly elaborated, cataloged as of poor quality CONCLUSIONS: The evaluation on the quality ofH. Cl. allowed identifying and highlighting the presence of a marked gap between the ideal purpose sought by the major curriculum and the final product as part of the professionalization process.

Dynamics of Calcium during In vitro Microspore Embryogenesis and In vivo Microspore Development in Brassica napus and Solanum melongena.

Calcium is widely known to have a role as a signaling molecule in many different processes, including stress response and activation of the embryogenic program. However, there are no direct clues about calcium levels during microspore embryogenesis, an experimental process that combines a developmental switch toward embryogenesis and the simultaneous application of different stressing factors. In this work, we used FluoForte, a calcium-specific fluorescent vital dye, to track by confocal microscopy the changes in levels and subcellular distribution of calcium in living rapeseed (B. napus) and eggplant (S. melongena) microspores and pollen grains during in vivo development, as well as during the first stages of in vitro-induced microspore embryogenesis in rapeseed. During in vivo development, a clear peak of cytosolic Ca2+ was observed in rapeseed vacuolate microspores and young pollen grains, the stages more suitable for embryogenesis induction. However, the Ca2+ levels observed in eggplant were dramatically lower than in rapeseed. Just after in vitro induction, Ca2+ levels increased specifically in rapeseed embryogenic microspores at levels dramatically higher than during in vivo development. The increase was observed in the cytosol, but predominantly in vacuoles. Non-embryogenic forms such as callus-like and pollen-like structures presented remarkably different calcium patterns. After the heat shock-based inductive treatment, Ca2+ levels progressively decreased in all cases. Together, our results reveal unique calcium dynamics in in vivo rapeseed microspores, as well as in those reprogrammed to in vitro embryogenesis, establishing a link between changes in Ca2+ level and subcellular distribution, and microspore embryogenesis.

An early dysregulation of FAK and MEK/ERK signaling pathways precedes the ß-amyloid deposition in the olfactory bulb of APP/PS1 mouse model of Alzheimer's disease.

UNLABELLED: Olfactory dysfunction is an early event of Alzheimer's disease (AD). However, the mechanisms associated to AD neurodegeneration in olfactory areas are unknown. Here we used double-transgenic amyloid precursor protein/presenilin 1 (APPswe/PS1dE9) mice and label-free quantitative proteomics to analyze early pathological effects on the olfactory bulb (OB) during AD progression. Prior to ß-amyloid plaque formation, 9 modulated proteins were detected on 3-month-old APP/PS1 mice while 16 differential expressed proteins were detected at 6months, when ß-amyloid plaques appear, indicating a moderate imbalance in cytoskeletal rearrangement, and synaptic plasticity in APP/PS1 OBs. Moreover, ß-amyloid induced an inactivation of focal adhesion kinase (FAK) together with a transient activation of MEK1/2, leading to inactivation of ERK1/2 in 6-months APP/PS1 OBs. In contrast, the analysis of human OBs revealed a late activation of FAK in advanced AD stages, whereas ERK1/2 activation was enhanced across AD staging respect to controls. This survival potential was accompanied by the inhibition of the proapototic factor BAD in the OB across AD phenotypes. Our data contribute to a better understanding of the early molecular mechanisms that are modulated in AD neurodegeneration, highlighting significant differences in the regulation of survival pathways between APP/PS1 mice and sporadic human AD. SIGNIFICANCE: Loss of smell is involved in early stages of Alzheimer's disease (AD), usually preceding classic disease symptoms. However, the mechanisms governing this dysfunction are still poorly understood, losing its potential as a useful tool for clinical diagnosis. Our study characterizes potential AD-associated molecular changes in APP/PS1 mice olfactory bulb (OB) using MS-quantitative proteomics, revealing early cytoskeletal disruption and synaptic plasticity impairment. Moreover, an opposite pattern was found when comparing the activation status of specific survival pathways between APP/PS1 OBs and OBs derived from sAD subjects with different neuropathological grading. Our data reflect, in part, the progressive effect of APP overproduction and Aß accumulation on the OB proteome during AD progression.

S-sulfhydration: a cysteine posttranslational modification in plant systems.

Hydrogen sulfide is a highly reactive molecule that is currently accepted as a signaling compound. This molecule is as important as carbon monoxide in mammals and hydrogen peroxide in plants, as well as nitric oxide in both eukaryotic systems. Although many studies have been conducted on the physiological effects of hydrogen sulfide, the underlying mechanisms are poorly understood. One of the proposed mechanisms involves the posttranslational modification of protein cysteine residues, a process called S-sulfhydration. In this work, a modified biotin switch method was used for the detection of Arabidopsis (Arabidopsis thaliana) proteins modified by S-sulfhydration under physiological conditions. The presence of an S-sulfhydration-modified cysteine residue on cytosolic ascorbate peroxidase was demonstrated using liquid chromatography-tandem mass spectrometry analysis, and a total of 106 S-sulfhydrated proteins were identified. Immunoblot and enzyme activity analyses of some of these proteins showed that the sulfide added through S-sulfhydration reversibly regulates the functions of plant proteins in a manner similar to that described in mammalian systems.

An improved quantitative mass spectrometry analysis of tumor specific mutant proteins at high sensitivity.

New disease specific biomarkers, especially for cancer, are urgently needed to improve individual diagnosis, prognosis, and treatment selection, that is, for personalized medicine. Genetic mutations that affect protein function drive cancer. Therefore, the detection of such mutations represents a source of cancer specific biomarkers. Here we confirm the implementation of the mutant protein specific immuno-SRM (where SRM is selective reaction monitoring) mass spectrometry method of RAS proteins reported by Wang et al. [Proc. Natl. Acad. Sci. USA 2011, 108, 2444-2449], which exploits an antibody to simultaneously capture the different forms of the target protein and the resolving power and sensitivity of LC-MS/MS and improve the technique by using a more sensitive mass spectrometer. The mutant form G12D was quantified by SRM on a QTRAP 5500 mass spectrometer and the MIDAS workflow was used to confirm the sequence of the targeted peptides. This assay has been applied to quantify wild type and mutant RAS proteins in patient tumors, xenografted human tissue, and benign human epidermal tumors at high sensitivity. The limit of detection for the target proteins was as low as 12 amol (0.25 pg). It requires low starting amounts of tissue (ca.15 mg) that could be obtained from a needle aspiration biopsy. The described strategy could find application in the clinical arena and be applied to the study of expression of protein variants in disease.

Proteomic analysis of human hepatoma cells expressing methionine adenosyltransferase I/III: Characterization of DDX3X as a target of S-adenosylmethionine.

Methionine adenosyltransferase I/III (MATI/III) synthesizes S-adenosylmethionine (SAM) in quiescent hepatocytes. Its activity is compromised in most liver diseases including liver cancer. Since SAM is a driver of hepatocytes fate we have studied the effect of re-expressing MAT1A in hepatoma Huh7 cells using proteomics. MAT1A expression leads to SAM levels close to those found in quiescent hepatocytes and induced apoptosis. Normalization of intracellular SAM induced alteration of 128 proteins identified by 2D-DIGE and gel-free methods, accounting for deregulation of central cellular functions including apoptosis, cell proliferation and survival. Human Dead-box protein 3 (DDX3X), a RNA helicase regulating RNA splicing, export, transcription and translation was down-regulated upon MAT1A expression. Our data support the regulation of DDX3X levels by SAM in a concentration and time dependent manner. Consistently, DDX3X arises as a primary target of SAM and a principal intermediate of its antitumoral effect. Based on the parallelism between SAM and DDX3X along the progression of liver disorders, and the results reported here, it is tempting to suggest that reduced SAM in the liver may lead to DDX3X up-regulation contributing to the pathogenic process and that replenishment of SAM might prove to have beneficial effects, at least in part by reducing DDX3X levels. This article is part of a Special Issue entitled: Proteomics: The clinical link.

Quantitative proteome and acidic subproteome profiling of Candida albicans yeast-to-hypha transition.

Candida albicans yeast-to-hypha morphological transition is involved in the virulence strategy of this opportunistic fungal pathogen. Changes in relative abundance of the Candida proteome related to this process were analyzed using different two-dimensional differential in-gel electrophoresis (2D-DIGE)-based approaches. First, a comparative analysis of yeast and hyphal cytoplasmic proteins allowed the detection of 106 protein spots with significant variation in abundance. Sixty-one of them, corresponding to 46 proteins, were identified. As most of the differentially abundant proteins had an acidic isoelectric point, a large-scale prefractionation approach to analyze the acidic C. albicans subproteome was carried out. Ninety acidic C. albicans proteins were identified by either gel-based or nongel-based approaches. Additionally, different workflows combining preparative isoelectric focusing, Cy labeling, and narrow pH gradient 2-DE gels were tested to analyze the differences in relative protein abundance between yeast and hyphal acidic subproteomes. It was possible to identify 21 differentially abundant acidic proteins; 10 of them were not identified in the previous 2D-DIGE gels. Functional and network interaction analyses of the 56 differentially abundant proteins identified by both approaches rendered an integrated view of metabolic and cellular process reorganization during the yeast-to-hypha transition. With these results, we propose a model of metabolic reorganization.