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241.
Tissue-specific organic acid metabolism in reproductive and non-reproductive parts of the fig fruit is partially induced by pollination 总被引:1,自引:0,他引:1
Kumar Lama Reut Peer Lyudmila Shlizerman Sagit Meir Adi Doron-Faigenboim Avi Sadka Asaph Aharoni Moshe A. Flaishman 《Physiologia plantarum》2020,168(1):133-147
Organic acids are important components of overall fruit quality through flavor, taste, nutritional and medicinal values. Pollinated fig (Ficus carica L.) fruit quality is enhanced by increased acidity. We quantified the major organic acids and characterized the expression pattern of organic acid metabolic pathway-related genes in the reproductive part – inflorescence and non-reproductive part – receptacle of parthenocarpic and pollinated fig fruit during ripening. Essentially, pollinated fruit contains seeds in the inflorescence, as opposed to no seeds in the parthenocarpic inflorescence. The major organic acids – citrate and malate – were found in relatively high quantities in the inflorescence compared to the receptacle of both parthenocarpic and pollinated fig fruit. Notably, pollination increased citric acid content significantly in both inflorescence and receptacle. Genes related to the phosphoenolpyruvate carboxylase (PEPC) cycle, tricarboxylic acid cycle, citrate catabolism and glyoxylate cycle were identified in fig fruit. Expression levels of most of these genes were higher in inflorescences than in receptacles. In particular, FcPEPC and FcFUM (encoding fumarase) had significantly higher expression in the inflorescence of pollinated fruit. Most importantly, expression of the glyoxylate cycle genes FcMLS and FcICL (encoding malate synthase and isocitrate lyase, respectively) was induced to strikingly high levels in the inflorescence by pollination, and their expression level was highly positively correlated with the contents of all organic acids. Therefore, the glyoxylate cycle may be responsible for altering the accumulation of organic acids to upgrade the fruit taste during ripening, especially in the pollinated, seeded inflorescence. 相似文献
242.
Plant and Soil - Unravelling the factors shaping microbial community structure across plant holobiont is required to promote plant health and crop productivity. We compared microbial communities in... 相似文献
243.
Susanto Febri Adi Wijayanti Putri Fauzia Anisa Nazera Komalasari Resta Dewi Nuringtyas Tri Rini Purwestri Yekti Asih 《Plant Cell, Tissue and Organ Culture》2020,141(3):605-617
Plant Cell, Tissue and Organ Culture (PCTOC) - Indonesian black rice has the potential to be developed as a functional food due to their high anthocyanin content and other nutritional benefits such... 相似文献
244.
Adi Nagler David W. Vredevoogd Michal Alon Phil F. Cheng Sophie Trabish Shelly Kalaora Rand Arafeh Victoria Goldin Mitchell P. Levesque Daniel S. Peeper Yardena Samuels 《Pigment cell & melanoma research》2020,33(2):334-344
NRAS mutations are the most common alterations among RAS isoforms in cutaneous melanoma, with patients harboring these aggressive tumors having a poor prognosis and low survival rate. The main line of treatment for these patients is MAPK pathway‐targeted therapies, such as MEK inhibitors, but, unfortunately, the response to these inhibitors is variable due to tumor resistance. Identifying genetic modifiers involved in resistance toward MEK‐targeted therapy may assist in the development of new therapeutic strategies, enhancing treatment response and patient survival. Our whole‐genome CRISPR‐Cas9 knockout screen identified the target Kelch domain‐containing F‐Box protein 42 (FBXO42) as a factor involved in NRAS‐mutant melanoma‐acquired resistance to the MEK1/2 inhibitor trametinib. We further show that FBXO42, an E3 ubiquitin ligase, is involved in the TAK1 signaling pathway, possibly prompting an increase in active P38. In addition, we demonstrate that combining trametinib with the TAK1 inhibitor, takinib, is a far more efficient treatment than trametinib alone in NRAS‐mutant melanoma cells. Our findings thus show a new pathway involved in NRAS‐mutant melanoma resistance and provide new opportunities for novel therapeutic options. 相似文献
245.
246.
Sylvain DeLisle Bernard Kim Janaki Deepak Tariq Siddiqui Adi Gundlapalli Matthew Samore Leonard D'Avolio 《PloS one》2013,8(8)
Background
Timely information about disease severity can be central to the detection and management of outbreaks of acute respiratory infections (ARI), including influenza. We asked if two resources: 1) free text, and 2) structured data from an electronic medical record (EMR) could complement each other to identify patients with pneumonia, an ARI severity landmark.Methods
A manual EMR review of 2747 outpatient ARI visits with associated chest imaging identified x-ray reports that could support the diagnosis of pneumonia (kappa score = 0.88 (95% CI 0.82∶0.93)), along with attendant cases with Possible Pneumonia (adds either cough, sputum, fever/chills/night sweats, dyspnea or pleuritic chest pain) or with Pneumonia-in-Plan (adds pneumonia stated as a likely diagnosis by the provider). The x-ray reports served as a reference to develop a text classifier using machine-learning software that did not require custom coding. To identify pneumonia cases, the classifier was combined with EMR-based structured data and with text analyses aimed at ARI symptoms in clinical notes.Results
370 reference cases with Possible Pneumonia and 250 with Pneumonia-in-Plan were identified. The x-ray report text classifier increased the positive predictive value of otherwise identical EMR-based case-detection algorithms by 20–70%, while retaining sensitivities of 58–75%. These performance gains were independent of the case definitions and of whether patients were admitted to the hospital or sent home. Text analyses seeking ARI symptoms in clinical notes did not add further value.Conclusion
Specialized software development is not required for automated text analyses to help identify pneumonia patients. These results begin to map an efficient, replicable strategy through which EMR data can be used to stratify ARI severity. 相似文献247.
248.
Lubna A. Al-Ansary Andrea C. Tricco Yaser Adi Ghada Bawazeer Laure Perrier Mohammed Al-Ghonaim Nada AlYousefi Mariam Tashkandi Sharon E. Straus 《PloS one》2013,8(1)
Background
Despite the availability of clinical practice guidelines (CPGs), optimal hypertension control is not achieved in many parts of the world; one of the challenges is the volume of guidelines on this topic and their variable quality. To systematically review the quality, methodology, and consistency of recommendations of recently-developed national CPGs on the diagnosis, assessment and the management of hypertension.Methodology/Principal Findings
MEDLINE, EMBASE, guidelines'' websites and Google were searched for CPGs written in English on the general management of hypertension in any clinical setting published between January 2006 and September 2011. Four raters independently appraised each CPG using the AGREE-II instrument and 2 reviewers independently extracted the data. Conflicts were resolved by discussion or the involvement of an additional reviewer. Eleven CPGs were identified. The overall quality ranged from 2.5 to 6 out of 7 on the AGREE-II tool. The highest scores were for “clarity of presentation” (44.4% −88.9%) and the lowest were for “rigour of development” (8.3%–30% for 9 CGPs). None of them clearly reported being newly developed or adapted. Only one reported having a patient representative in its development team. Systematic reviews were not consistently used and only 2 up-to-date Cochrane reviews were cited. Two CPGs graded some recommendations and related that to levels (but not quality) of evidence. The CPGs'' recommendations on assessment and non-pharmacological management were fairly consistent. Guidelines varied in the selection of first-line treatment, adjustment of therapy and drug combinations. Important specific aspects of care (e.g. resistant hypertension) were ignored by 6/11 CPGs. The CPGs varied in methodological quality, suggesting that their implementation might not result in less variation of care or in better health-related outcomes.Conclusions/Significance
More efforts are needed to promote the realistic approach of localization or local adaptation of existing high-quality CPGs to the national context. 相似文献249.
N-glycosylation is a post-translational modification performed by members of all three domains of life. Studies on the halophile Haloferax volcanii have offered insight into the archaeal version of this universal protein-processing event. In the present study, AglQ was identified as a novel component of the pathway responsible for the assembly and addition of a pentasaccharide to select Asn residues of Hfx. volcanii glycoproteins, such as the S-layer glycoprotein. In cells deleted of aglQ, both dolichol phosphate, the lipid carrier used in Hfx. volcanii N-glycosylation, and modified S-layer glycoprotein Asn residues only presented the first three pentasaccharide subunits, pointing to a role for AglQ in either preparing the third sugar for attachment of the fourth pentasaccharide subunit or processing the fourth sugar prior to its addition to the lipid-linked trisaccharide. To better define the precise role of AglQ, shown to be a soluble protein, bioinformatics tools were recruited to identify sequence or structural homologs of known function. Site-directed mutagenesis experiments guided by these predictions identified residues important for AglQ function. The results obtained point to AglQ acting as an isomerase in Hfx. volcanii N-glycosylation. 相似文献
250.
Gad David Vatine David Zada Tali Lerer-Goldshtein Adi Tovin Guy Malkinson Karina Yaniv Lior Appelbaum 《The Journal of biological chemistry》2013,288(1):169-180
Allan-Herndon-Dudley syndrome (AHDS) is a severe psychomotor retardation characterized by neurological impairment and abnormal thyroid hormone (TH) levels. Mutations in the TH transporter, monocarboxylate transporter 8 (MCT8), are associated with AHDS. MCT8 knock-out mice exhibit impaired TH levels; however, they lack neurological defects. Here, the zebrafish mct8 gene and promoter were isolated, and mct8 promoter-driven transgenic lines were used to show that, similar to humans, mct8 is primarily expressed in the nervous and vascular systems. Morpholino-based knockdown and rescue experiments revealed that MCT8 is strictly required for neural development in the brain and spinal cord. This study shows that MCT8 is a crucial regulator during embryonic development and establishes the first vertebrate model for MCT8 deficiency that exhibits a neurological phenotype. 相似文献