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Flueggea virosa (Roxb. ex Willd.) Royle, an evergreen shrub and small tree in the Phyllanthaceae family, holds significant potential in garden landscaping and pharmacological applications. However, the lack of genomic data has hindered further scientific understanding of its horticultural and medicinal values. In this study, we have assembled a haplotype-resolved genome of F. virosa for the first time. The two haploid genomes, named haplotype A genome and haplotype B genome, are 487.33 Mb and 477.53 Mb in size, respectively, with contig N50 lengths of 31.45 Mb and 32.81 Mb. More than 99% of the assembled sequences were anchored to 13 pairs of pseudo-chromosomes. Furthermore, 21,587 and 21,533 protein-coding genes were predicted in haplotype A and haplotype B genomes, respectively. The availability of this chromosome-level genome fills the gap in genomic data for F. virosa and provides valuable resources for molecular studies of this species, supporting future research on speciation, functional genomics, and comparative genomics within the Phyllanthaceae family.
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Génome végétal , Chromosomes de plante , Haplotypes , Annotation de séquence moléculaireRÉSUMÉ
Dracaena cambodiana Pierre ex Gagn. (Asparagaceae) is the source plant of Dragon's blood and has high ornamental values in gardening. Currently, this species is classified as the second-class state-protected species in the National Key Protected Wild Plants (NKPWP) of China. However, limited genomic data has hindered a more comprehensive scientific understanding of the processes involved in the production of Dragon's blood and the related conservation genomics research. In this study, we assembled a haplotype-resolved genome of D. cambodiana. The haploid genomes, haplotype A and haplotype B, are 1,015.22 Mb and 1,003.13 Mb in size, respectively. The completeness of haplotype A and haplotype B genomes was 98.60% and 98.20%, respectively, using the "embryophyta_10" dataset. Haplotype A and haplotype B genomes contained 27,361 and 27,066 protein-coding genes, respectively, with nearly all being functionally annotated. These findings provide new insights into the genomic characteristics of D. cambodiana and will offer additional genomic resources for studying the biosynthesis mechanism of Dragon's blood and the horticultural application of Dragon trees.
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Dracaena , Génome végétal , Haplotypes , Dracaena/génétique , Chine , Chromosomes de plante/génétique , Extraits de plantesRÉSUMÉ
BACKGROUND: Percutaneous transhepatic stent placement has become a common strategy for the postoperative treatment of portal vein (PV)/superior mesenteric veins (SMV) stenosis/occlusion. It has been widely used after liver transplantation surgery; however, reports on stent placement for acute PV/SMV stenosis after pancreatic surgery within postoperative 3 d are rare. CASE SUMMARY: Herein, we reported a case of intestinal edema and SMV stenosis 2 d after pancreatic surgery. The patient was successfully treated using stent grafts. Although the stenosis resolved after stent placement, complications, including bleeding, pancreatic fistula, bile leakage, and infection, made the treatment highly challenging. The use of anticoagulants was adjusted multiple times to prevent venous thromboembolism and the risk of bleeding. After careful treatment, the patient stabilized, and stent placement effectively managed postoperative PV/SMV stenosis. CONCLUSION: Stent placement is effective and feasible for treating acute PV/SMV stenosis after pancreatic surgery even within postoperative 3 d.
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OBJECTIVES: Previously, Interferon-induced Protein with Tetratricopeptide Repeats 1 (IFIT1) has been shown to promote cancer development. Here, we aimed to explore the role of IFIT1 in the development and progression of pancreatic cancer, including the underlying mechanisms. METHODS: We explored IFIT1 expression in pancreatic cancer samples using The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets. Cell Counting Kit-8 (CCK8), colony formation, scratch wound-healing and Transwell assays were performed to assess the proliferation, migration and invasion abilities of pancreatic cancer cells. Gene Set Enrichment Analysis (GSEA) and Western blotting were performed to assess the regulatory effect of IFIT1 on the Wnt/ß-catenin pathway. RESULTS: We found that upregulation of IFIT1 expression is common in pancreatic cancer and is negatively associated with overall patient survival. Knockdown of IFIT1 expression led to decreased proliferation, migration and invasion of pancreatic cancer cells. We also found that IFIT1 could regulate Wnt/ß-catenin signaling, and that a Wnt/ß-catenin agonist could reverse this effect. In addition, we found that IFIT1 can promote epithelial-mesenchymal transition (EMT) of pancreatic cancer cells. CONCLUSIONS: Our data indicate that IFIT1 increases pancreatic cancer cell proliferation, migration and invasion by activating the Wnt/ß-catenin pathway. In addition, we found that EMT could be regulated by IFIT1. IFIT1 may serve as a potential therapeutic target for pancreatic cancer.
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Protéines adaptatrices de la transduction du signal , Mouvement cellulaire , Prolifération cellulaire , Transition épithélio-mésenchymateuse , Régulation de l'expression des gènes tumoraux , Invasion tumorale , Tumeurs du pancréas , Protéines de liaison à l'ARN , Voie de signalisation Wnt , Humains , Tumeurs du pancréas/anatomopathologie , Tumeurs du pancréas/génétique , Tumeurs du pancréas/métabolisme , Prolifération cellulaire/génétique , Mouvement cellulaire/génétique , Voie de signalisation Wnt/génétique , Lignée cellulaire tumorale , Transition épithélio-mésenchymateuse/génétique , Protéines de liaison à l'ARN/métabolisme , Protéines de liaison à l'ARN/génétique , Protéines adaptatrices de la transduction du signal/métabolisme , Protéines adaptatrices de la transduction du signal/génétique , bêta-Caténine/métabolisme , Protéines de transport/métabolisme , Protéines de transport/génétiqueRÉSUMÉ
Yeast is widely studied in producing biofuels and biochemicals using renewable biomass. Among various yeasts, Saccharomyces cerevisiae has been particularly recognized as an important yeast cell factory. However, economic bioproduction using S. cerevisiae is challenged by harsh environments during fermentation, among which inhibitory chemicals in the culture media or toxic products are common experiences. Understanding the stress-responsive mechanisms is conducive to developing robust yeast strains. Here, we review recent progress in mechanisms underlying yeast stress response, including regulation of cell wall integrity, membrane transport, antioxidative system, and gene transcription. We highlight epigenetic regulation of stress response and summarize manipulation of yeast stress tolerance for improved bioproduction. Prospects in the application of machine learning to improve production efficiency are also discussed.
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Épigenèse génétique , Saccharomyces cerevisiae , Saccharomyces cerevisiae/génétique , Saccharomyces cerevisiae/métabolisme , Éthanol/métabolisme , Fermentation , BiocarburantsRÉSUMÉ
Chromatin remodelers are important in maintaining the dynamic chromatin state in eukaryotic cells, which is essential for epigenetic regulation. Among the remodelers, the multi-subunits complex INO80 plays crucial roles in transcriptional regulation. However, current knowledge of chromatin regulation of the core subunit Ino80 on stress adaptation remains mysterious. Here we revealed that overexpressing the chromatin remodeler Ino80 elevated tolerance to multiple stresses in budding yeast Saccharomyces cerevisiae. Analyses of differential chromatin accessibility and global transcription levels revealed an enrichment of genes involved in NCR (nitrogen catabolite repression) under acetic acid stress. We demonstrated that Ino80 overexpression reduced the histone H3 occupancy in the promoter region of the glutamate dehydrogenase gene GDH2 and the allantoinase gene DAL1. Consistently, the decreased occupancy of nucleosome was revealed in the Ino80-inactivation mutant. Further analyses showed that Ino80 was recruited to the specific DNA locus in the promoter region of GDH2. Consistently, Ino80 overexpression facilitated the utilization of non-preferred nitrogen source to enhance ethanol yield under prolonged acetic acid stress. These results demonstrate that Ino80 plays a crucial role in coordinating carbon and nitrogen metabolism during stress adaptation.
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Répression catabolique , Protéines de Saccharomyces cerevisiae , Saccharomyces cerevisiae/métabolisme , Chromatine/métabolisme , Protéines de Saccharomyces cerevisiae/génétique , Épigenèse génétique , Nucléosomes , Acétates/métabolismeRÉSUMÉ
Background: Armadillo repeat-containing 10 (ARMC10) is involved in the progression of multiple types of tumors. Pancreatic adenocarcinoma (PAAD) is a lethal disease with poor survival and prognosis. Methods: We acquired the data of ARMC10 in PAAD patients from the cancer genome atlas (TCGA) and gene expression omnibus (GEO) datasets and compared the expression level with normal pancreatic tissues. We evaluated the relevance between ARMC10 expression and clinicopathological factors, immune infiltration degree and prognosis in PAAD. Results: High expression of ARMC10 was relevant to T stage, M stage, pathologic stage, histologic grade, residual tumor, primary therapy outcome (P < 0.05) and related to lower Overall-Survival (OS), Disease-Specific Survival (DSS), and Progression-Free Interval (PFI). Gene set enrichment analysis showed that ARMC10 was related to methylation in neural precursor cells (NPC), G alpha (i) signaling events, APC targets, energy metabolism, potassium channels and IL10 synthesis. The expression level of ARMC10 was positively related to the abundance of T helper cells and negatively to that of plasmacytoid dendritic cells (pDCs). Knocking down of ARMC10 could lead to lower proliferation, invasion, migration ability and colony formation rate of PAAD cells in vitro. Conclusions: Our research firstly discovered ARMC10 as a novel prognostic biomarker for PAAD patients and played a crucial role in immune regulation in PAAD.
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Liparis Richard (Malaxideae, Epidendroideae) is a large and diverse genus of the family Orchidaceae, the taxonomy of which is complicated and controversial. In this study, we sequenced, assembled and analyzed four complete chloroplast genomes of Liparis species including L. kumokiri, L. makinoana, L. pauliana, and L. viridiflora, and evaluated their phylogenetic relationships with related species for the first time. These four chloroplast genomes (size range 153,095 to 158,239 bp) possess typical quadripartite structures that consist of a large single copy (LSC, 83,533-86,752 bp), a small single copy (SSC, 17,938-18,156 bp) and a pair of inverted repeats (IRs, 26,421-26,933 bp). The genomes contain 133 genes, including 87 protein coding genes, 38 tRNAs and 8 rRNA genes. The genome arrangements, gene contents, gene order, long repeats and simple sequence repeats were similar with small differences observed among these four chloroplast genomes. Five highly variable regions including ycf1, ndhA, ndhF, trnQ and trnK were identified from the comparative analysis with other nine related Liparis species, which had the potential to be used as DNA markers for species identification and phylogenetic studies of Liparis species. Phylogenetic analysis based on the complete chloroplast genome sequences strongly supported the polyphyly of Liparis and its further division into three branches. These results provided valuable information to illustrate the complicated taxonomy, phylogeny and evolution process of the Liparis genus.
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Génome de chloroplaste , Orchidaceae , Phylogenèse , Génomique/méthodes , Orchidaceae/génétique , Marqueurs génétiquesRÉSUMÉ
BACKGROUND: Delayed gastric emptying (DGE) remains one of the major complications after pancreaticoduodenectomy (PD), with discrepant reports of its contributing factors. This study aimed to develop a nomogram to identify potential predictors and predict the probability of DGE after PD. METHODS: This retrospective study enrolled 422 consecutive patients who underwent PD from January 2019 to December 2021 at our institution. The LASSO algorithm and multivariate logistic regression were performed to identify independent risk and protective factors associated with clinically relevant delayed gastric emptying (CR-DGE). A nomogram was established based on the selected variables. Then, the calibration curve, ROC curve, decision curve analysis (DCA), and clinical impact curve (CIC) were applied to evaluate the predictive performance of our model. Finally, an independent cohort of 45 consecutive patients from January 2022 to March 2022 was enrolled to further validate the nomogram. RESULTS: Among 422 patients, CR-DGE occurred in 94 patients (22.2%). A previous history of chronic gastropathy, intraoperative plasma transfusion ≥ 400 ml, end-to-side gastrointestinal anastomosis, intra-abdominal infection, incisional infection, and clinically relevant postoperative pancreatic fistula (CR-POPF) were identified as risk predictors. Minimally invasive pancreaticoduodenectomy (MIPD) was demonstrated to be a protective predictor of CR-DGE. The areas under the curve (AUCs) were 0.768 (95% CI, 0.706-0.830) in the development cohort, 0.766 (95% CI, 0.671-0.861) in the validation cohort, and 0.787 (95% CI, 0.633-0.940) in the independent cohort. Then, we built a simplified scale based on our nomogram for risk stratification. CONCLUSIONS: Our study identified seven predictors and constructed a validated nomogram that effectively predicted CR-DGE for patients who underwent PD.
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Gastroparésie , Duodénopancréatectomie , Humains , Duodénopancréatectomie/effets indésirables , Gastroparésie/épidémiologie , Gastroparésie/étiologie , Études rétrospectives , Transfusion de composants du sang/effets indésirables , Facteurs de risque , Plasma sanguin , Anastomose chirurgicale/effets indésirables , Appréciation des risques , Complications postopératoires/épidémiologie , Complications postopératoires/étiologie , Vidange gastriqueRÉSUMÉ
OBJECTIVE: To summarize the surgical treatment of different proximal clavicle fractures, and discuss the classification of proximal clavicle fractures. METHODS: Total of 24 patients with displaced proximal clavicle fractures were treated from January 2017 to December 2020 including 16 males and 8 females, aged 28 to 66 years old. Among them, 20 cases were fresh fractures and 4 cases were old fractures. According to the Edinburgh classification, 14 cases were type 1B1 fractures and 10 cases were type 1B2 fractures. The different internal fixation methods were selected for internal fixation treatment according to different fracture types.The operation time, blood loss, preoperative and postoperative displacement difference, fracture healing time and Rockwood scoring system were recorded. RESULTS: All patients were followed up for 12 to 24 months. There were no patients with infection or loss of reduction after the operation. Three patients had internal fixation failure after operation, and the internal fixation device was removed. Results The operation time was 30 to 65 min, and the blood loss was 15 to 40 ml. No important nerves, blood vessels, or organs were damaged. The imaging healing time was 3 to 6 months. According to the Rockwood functional score, the total score was (13.50±1.86), pain (2.57±0.50), range of motion (2.78±0.41), muscle strength (2.93±0.28), restricted daily activity (2.85±0.35), subjective results (2.63±0.61);the results were excellent in 20 cases, good in 3 cases, fair in 1 case. CONCLUSION: Proximal clavicular fracture is a type of fracture with low incidence. According to different fracture types, different internal fixation methods and treatment methods can be selected, and satisfactory surgical results can be achieved.
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Clavicule , Fractures osseuses , Mâle , Femelle , Humains , Adulte , Adulte d'âge moyen , Sujet âgé , Clavicule/chirurgie , Résultat thérapeutique , Plaques orthopédiques , Fractures osseuses/chirurgie , Ostéosynthèse interne/méthodes , Études rétrospectivesRÉSUMÉ
Purpose: Genotyping is fundamental in papillary thyroid cancer (PTC) and helps to enhance diagnosis and prognosis and determine appropriate treatments. The phenotype-genotype association in PTC was previously studied, with BRAF V600E characterizing classic PTC and tall-cell PTC and RAS mutations characterizing follicular-variant PTC. In clinic, some non-classical histological subtypes of PTC were also identified, however, their genotype remains unclear. In this study, we collected samples of these non-classical PTC after the exclusion of classic phenotypes and examined their phenotypes, genotype and the relationship between phenotype and genotype. Methods: We screened out non-classical PTC by excluding classical PTC from 1,059 different thyroid samples, and a total of 24 cases was obtained and described from the morphological features, which is rare in differentiated PTC. DNA/RNA sequencing was performed using 18 available samples to describe the genetic features. Results: PTC with the non-classical phenotype were characterized cuboidal to low columnar tumor cells with subtle nuclear features of PTC and without discernible nuclear elongation, concurrently with dense microfollicles, delicate papillae or solid nodules with delicate fibrovascular cores. They were associated with lymphatic vessel invasion (P<0.001) but not with a worse prognosis (P=0.791). Gene fusions were identified in 14 of 18 (77.8%) cases, including eight fusions of NTRK and six fusions of RET. The high percentage of fusions in this papillary thyroid cancer subgroup suggested a correlation of gene fusions with the phenotype that does not belong to the BRAF V600E-mutant or RAS-mutant group. Conclusions: Our study retrospectively screened a large cohort of different thyroid tissue samples, and presented the histopathological and genetic features of a non-classical phenotype of PTC from 24 patients. It may contribute to diagnose in PTC, and patients of these non-classical phenotype may benefit from targeted therapy, compared to a natural patient cohort without selection.
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Carcinome papillaire , Tumeurs de la thyroïde , Humains , Cancer papillaire de la thyroïde/diagnostic , Cancer papillaire de la thyroïde/génétique , Cancer papillaire de la thyroïde/anatomopathologie , Protéines proto-oncogènes B-raf/génétique , Études rétrospectives , Carcinome papillaire/diagnostic , Carcinome papillaire/génétique , Carcinome papillaire/anatomopathologie , Tumeurs de la thyroïde/diagnostic , Tumeurs de la thyroïde/génétique , Tumeurs de la thyroïde/anatomopathologie , PhénotypeRÉSUMÉ
Objective: We aimed to describe the morphological characteristics of Danis-Weber type B lateral malleolar fractures, with special attention given to the end-tip locations of fracture apexes, and to construct a 3D (three-dimensional) fracture line map. Methods: A total of 114 surgically treated cases of type B lateral malleolar fractures were retrospectively reviewed. The baseline data were collected, and computed tomography data were reconstructed in a 3D model. We measured the morphological characteristics and the end-tip location of the fracture apex on the 3D model. All the fracture lines were superimposed on a template fibula to generate a 3D fracture line map. Results: Among these 114 cases, 21 were isolated lateral malleolar fractures, 29 were bimalleolar fractures, and 64 were trimalleolar fractures. All the type B lateral malleolar fractures demonstrated a spiral or oblique fracture line. As measured from the distal tibial articular line, the fracture started at -6.22 ± 4.62 mm anteriorly and terminated at 27.23 ± 12.32 mm posteriorly, and the average fracture height was 33.45 ± 11.89 mm. The fracture line inclination angle was 56.85° ± 9.58°, and the total fracture spiral angle was 269.81° ± 37.09°, with fracture spikes of 156.20° ± 24.04°. The proximal end-tip location of the fracture apex was classified into four zones in the circumferential cortex: zone I (lateral ridge) in seven cases (6.1%), zone II (posterolateral surface) in 65 cases (57%), zone III (posterior ridge) in 39 cases (34.2%), and zone IV (medial surface) in three cases (2.6%). Altogether, 43% (49 cases) of fracture apexes were not distributed on the posterolateral surface of the fibula, as 34.2% (39 cases) were located on the posterior ridge (zone III). The aforementioned morphological parameters in fractures with zone III, sharp spikes, and further broken spikes were greater than those in zone II, blunt spikes, and fractures without further broken spikes. The 3D fracture map suggested that the fracture lines with the zone-III apex were steeper and longer than those with the zone-II apex. Conclusion: Nearly half of type B lateral malleolar fractures had their proximal end-tip of apexes not on the posterolateral surface, which may impair the mechanical application of antiglide plates. A steeper fracture line and longer fracture spike indicate a more posteromedial distribution of the fracture end-tip apex.
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Herein, A novel gold-silver alloy nanobox (AuAgNB)@SiO2-gold nanosphere (AuNP) nanoassembly based on core-shell-satellite structure is fabricated and applied to the surface-enhanced Raman scattering (SERS) detection of S100 calcium-binding protein B protein (S100B). It contains an anisotropic hollow porous AuAgNB core with rough surface, an ultrathin silica interlayer labeled with reporter molecules, and AuNP satellites. The nanoassemblies were systematically optimized by tuning the reporter molecules concentration, silica layer thickness, AuAgNB size, and the size and number of AuNP satellite size. Remarkably, AuNP satellites are adjacent to AuAgNB@SiO2, developing AuAg-SiO2-Au heterogeneous interface. With the strong plasmon coupling between AuAgNB and AuNP satellites, chemical enhancement from heterogeneous interface, and the tip "hot spots" of AuAgNB, the SERS activity of the nanoassemblies was multiply enhanced. Additionally, the stability of nanostructure and Raman signal was significantly improved by the silica interlayer and AuNP satellites. Eventually, the nanoassemblies were applied for S100B detection. It demonstrated satisfactory sensitivity and reproducibility with a wide detection range of 10 fg/mL-10 ng/mL and a limit of detection (LOD) of 1.7 fg/mL. This work based on the AuAgNB@SiO2-AuNP nanoassemblies with multiple SERS enhancements and favorable stability demonstrates the promising application in stroke diagnosis.
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Nanoparticules métalliques , Silice , Silice/composition chimique , Reproductibilité des résultats , Nanoparticules métalliques/composition chimique , Analyse spectrale Raman , Or/composition chimiqueRÉSUMÉ
OBJECTIVE: With the help of finite element analysis, to explore the effect of proximal humeral bone cement enhanced screw plate fixation on the stability of internal fixation of osteoporotic proximal humeral fracture. METHODS: The digital model of unstable proximal humeral fracture with metaphyseal bone defect was made, and the finite element models of proximal humeral fracture bone cement enhanced screw plate fixation and common screw plate fixation were established respectively. The stress of cancellous bone around the screw, the overall stiffness, the maximum stress of the plate and the maximum stress of the screw were analyzed. RESULTS: The maximum stresses of cancellous bone around 6 screws at the head of proximal humeral with bone cement enhanced screw plate fixation were 1.07 MPa for No.1 nail, 0.43 MPa for No.2 nail, 1.16 MPa for No.3 nail, 0.34 MPa for No.4 nail, 1.99 MPa for No.5 nail and 1.57 MPa for No.6 nail. These with common screw plate fixation were:2.68 MPa for No.1 nail, 0.67 MPa for No.2 nail, 4.37 MPa for No.3 nail, 0.75 MPa for No.4 nail, 3.30 MPa for No.5 nail and 2.47 MPa for No.6 nail. Overall stiffness of the two models is 448 N/mm for bone cement structure and 434 N/mm for common structure. The maximum stress of plate appears in the joint hole:701MPa for bone cement structure and 42 0MPa for common structure. The maximum stress of screws appeared at the tail end of No.4 nail:284 MPa for bone cement structure and 240.8 MPa for common structure. CONCLUSION: Through finite element analysis, it is proved that the proximal humerus bone cement enhanced screw plate fixation of osteoporotic proximal humeral fracture can effectively reduce the stress of cancellous bone around the screw and enhance the initial stability after fracture operation, thus preventing from penetrating out and humeral head collapsing.
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Ciments osseux , Fractures de l'épaule , Humains , Analyse des éléments finis , Poly(méthacrylate de méthyle) , Phénomènes biomécaniques , Fractures de l'épaule/chirurgie , Ostéosynthèse interne , Tête de l'humérus , Vis orthopédiques , Plaques orthopédiquesRÉSUMÉ
Few studies explore the effects of nitrogen forms on exotic plant invasions, and all of them are conducted from the perspective of nitrogen form utilization without considering the effects of ammonium toxicity. The invasive plant Xanthium strumarium prefers to use nitrate, while its native congener X. sibiricum prefers to use ammonium, and the invader is more sensitive to high ammonium based on our preliminary observations. To further reveal the effects of nitrogen forms on invasiveness of X. strumarium, we studied the difference and related physiological mechanisms in sensitivity to ammonium between these species. With increasing ammonium, total biomass, root to shoot ratio and leaf chlorophyll content of X. strumarium decreased, showing ammonium toxicity. For X. sibiricum, however, ammonium toxicity did not occurr. With increasing ammonium, ammonium concentration increased in leaves and roots of X. strumarium, which is associated with the decreased activities of glutamine synthetase and glutamate synthase and the increased ammonium uptake; and consequently the contents of hydrogen peroxide and malondialdehyde also increased, which is associated with the decreased contents of reduced glutathione and ascorbic acid. By contrast, the abilities of ammonium assimilation and antioxidation of X. sibiricum were less affected by the increase of ammonium, and the contents of ammonium nitrogen, hydrogen peroxide and malondialdehyde in leaves and roots were significantly lower than those in X. strumarium. Our results indicate that ammonium accumulation and oxidative damage may be the physiological mechanisms for the ammonium toxicity of X. strumarium, providing a possible explanation that it generally invades nitrate-dominated and disturbed habitats and a theoretical basis for future studies on the control of invasive plants by regulating soil nitrogen.
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Sustainable bioproduction usingcarbon neutral feedstocks, especially lignocellulosic biomass, has attracted increasing attention due to concern over climate change and carbon reduction. Consolidated bioprocessing (CBP) of lignocellulosic biomass using recombinantyeast of Saccharomyces cerevisiaeis a promising strategy forlignocellulosic biorefinery. However, the economic viability is restricted by low enzyme secretion levels.For more efficient CBP, MIG1spsc01isolated from the industrial yeast which encodes the glucose repression regulator derivative was overexpressed. Increased extracellular cellobiohydrolase (CBH) activity was observed with unexpectedly decreased cell wall integrity. Further studies revealed that disruption ofCWP2, YGP1, andUTH1,which are functionally related toMIG1spsc01, also enhanced CBH secretion. Subsequently, improved cellulase production was achieved by simultaneous disruption ofYGP1and overexpression ofSED5, which remarkably increased extracellular CBH activity of 2.2-fold over the control strain. These results provide a novel strategy to improve the CBP yeast for bioconversion of carbon neutral biomass.
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Cellulase , Saccharomyces cerevisiae , Saccharomyces cerevisiae/métabolisme , Biomasse , Carbone/métabolisme , Cellulase/métabolisme , Cellulose 1,4-beta-cellobiosidase/génétique , Cellulose 1,4-beta-cellobiosidase/métabolisme , Paroi cellulaire/métabolisme , FermentationRÉSUMÉ
Increasing evidence from low-latitude ranges has demonstrated that native parasitic plants are promising biocontrol agents for some major invasive weeds. However, related mechanisms and the effect of environments on the control effect of the parasite are still unclear. In addition, few related studies have been conducted in high latitude (>40°), where the exotic plant richness is the highest in the globe, but natural enemies are relatively scarce. During field surveys, a Cuscuta species was found on the cosmopolitan invasive weed Ambrosia trifida L. in Shenyang, northeast China. Here, we first studied the impacts of the parasite on the invader at three sites with different light regimes and related mechanisms, then the haustorial connections between the parasite and the invader using anatomy and measurement of carbon (C) and nitrogen (N) stable isotope compositions (δ13C, δ15N), and finally identified the parasite using two molecular marks. The parasite was identified as C. japonica Choisy. This native holoparasitic vine posed serious C rather than N limitation to the invader, explaining its greatly inhibitory effects on the invader. Its negative effects were stronger on reproductive relative to vegetative growth, and at high relative to low light habitats, which indicated that the higher the vigor of the host is, the higher the impact of the parasite pose. The parasite could establish haustorial connections with phloem, xylem, and pith of the invader and thus obtain resources from both leaves and roots, which was confirmed by difference of δ13C and δ15N between the two species. The parasite had significantly higher leaf C concentrations and δ13C than its invasive host, being a strong C sink of the parasitic association. Our results indicate that C. japonica may be a promising biological control agent for the noxious invader in China.
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Production of biofuels and biochemicals from xylose using yeast cell factory is of great interest for lignocellulosic biorefinery. Our previous studies revealed that a natural yeast isolate Saccharomyces cerevisiae YB-2625 has superior xylose-fermenting ability. Through integrative omics analysis, NGG1, which encodes a transcription regulator as well as a subunit of chromatin modifying histone acetyltransferase complexes was revealed to regulate xylose metabolism. Deletion of NGG1 in S. cerevisiae YRH396h, which is the haploid version of the recombinant yeast using S. cerevisiae YB-2625 as the host strain, improved xylose consumption by 28.6%. Comparative transcriptome analysis revealed that NGG1 deletion down-regulated genes related to mitochondrial function, TCA cycle, ATP biosynthesis, respiration, as well as NADH generation. In addition, the NGG1 deletion mutant also showed transcriptional changes in amino acid biosynthesis genes. Further analysis of intracellular amino acid content confirmed the effect of NGG1 on amino acid accumulation during xylose utilization. Our results indicated that NGG1 is one of the core nodes for coordinated regulation of carbon and nitrogen metabolism in the recombinant S. cerevisiae. This work reveals novel function of Ngg1p in yeast metabolism and provides basis for developing robust yeast strains to produce ethanol and biochemicals using lignocellulosic biomass.
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Background: Phospholipase A/acyltransferase (PLAAT) family exhibits O- and N-acyltransferase activity and biosynthesize N-acylated ethanolamine phospholipids. Previously, PLAAT4 was seen as a tumor suppressor, but the exact function of PLAAT4 in pancreatic cancer was still unknown. In this study, we investigated the relationship of PLAAT4 and pancreatic cancer. Methods: Using the data from the cancer genome atlas (TCGA), Genotype-Tissue Expression (GTEx) database and Gene Expression Omnibus (GEO) datasets we compared the expression of PLAAT4 in normal and tumor tissues and analyzed the connections between PLAAT4 and several clinicopathological factors. Further, we conducted Gene ontology (GO) analysis, Gene set enrichment analysis (GSEA), single sample gene set enrichment analysis (ssGSEA) and estimate analysis to explore the association between PLAAT4 and biological function and immune infiltration. In addition, Kaplan-Meier (KM) analysis, univariate and multivariate Cox analysis were used to explore the association between PLAAT4 and prognosis. In addition, we plotted a nomogram according to the multivariate cox analysis visualizing the predictive ability of PLAAT4 on prognosis. In addition, we explore the influence of PLAAT4 on malignant behaviors of the pancreatic cancer cells in vitro. Results: After comparing the expression of PLAAT4 in normal and tumor tissues, we found that the expression of PLAAT4 was significantly high in pancreatic ductal adenocarcinoma (PDAC) samples. In addition, the results of GO and GSEA found that the expression of PLAAT4 was related to cell cycle checkpoints, M phase, regulation by p53, cell cycle mitotic and etc. Further, ssGSEA has shown that PLAAT4 was positively related to the abundance of aDC, Th1 cells, Th2 cells and negatively related to the Th17 cells. Subsequently, KM analysis, univariate and multivariate Cox analysis were used to analyze the correlation between PLAAT4 and prognosis. Additionally, we found that higher expression of PLAAT4 was related to T stage, N stage, histologic grade, etc (P < 0.05) and has a significant correlation with poor Overall Survival (OS), Disease-Specific Survival (DSS) and Progression-Free Interval (PFI). At last, we proved that PLAAT4 contributed to the malignant behaviors of the pancreatic cancer cells. Conclusion: This study indicated PLAAT4 as a novel prognostic biomarker and an important molecular that mediated immune response in pancreatic cancer.