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A novel coagulase-negative Staphylococcus strain (H164T) was isolated from soymilk in Taiwan. Comparative sequence analysis of the 16S rRNA gene revealed that the H164T strain is a member of the genus Staphylococcus. We used multilocus sequence analysis (MLSA) and phylogenomic analyses to demonstrate that the novel strain was closely related to Staphylococcus gallinarum, Staphylococcus nepalensis, Staphylococcus cohnii, and Staphylococcus urealyuticus. The average nucleotide identity and digital DNA-DNA hybridization values between H164T and its closest relatives were <95% and <70%, respectively. The H164T strain could also be distinguished from its closest relatives by the fermentation of d-fructose, d-maltose, d-trehalose, and d-mannitol, as well as by the activities of α-glucosidase and alkaline phosphatase. The major cellular fatty acids were C15:0 iso and C15:0 anteiso, and the predominant menaquinones were MK-7 and MK-8, respectively. The major cellular fatty acids and predominant menaquinones were C15:0 iso and C15:0 anteiso and MK-7 and MK-8, respectively. In conclusion, this strain represents a novel species, named Staphylococcus hsinchuensis sp. nov., with the type strain H164T (=BCRC 81404T = NBRC 116174T).
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Gametophyte development in angiosperms occurs within diploid sporophytic structures and requires coordinated development; e.g., development of the male gametophyte pollen depends on the surrounding sporophytic tissue, the tapetum. The mechanisms underlying this interaction remain poorly characterized. The peptide CLAVATA3/EMBRYO SURROUNDING REGION-RELATED 19 (CLE19) plays a "braking" role in preventing the harmful overexpression of tapetum transcriptional regulators to ensure normal pollen development in Arabidopsis. However, the CLE19 receptor is unknown. Here, we show that CLE19 interacts directly with the PXY-LIKE1 (PXL1) ectodomain and induces PXL1 phosphorylation. PXL1 is also required for the function of CLE19 in maintaining the tapetal transcriptional regulation of pollen exine genes. Additionally, CLE19 induces the interactions of PXL1 with SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE (SERK) coreceptors required for pollen development. We propose that PXL1 and SERKs act as receptor and coreceptor, respectively, of the extracellular CLE19 signal, thereby regulating tapetum gene expression and pollen development.
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Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Pólen/metabolismo , Peptídeos/genética , Peptídeos/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
Background: Previous reports suggested the clinical predictions of survival (CPS) and prognostic scores had similar accuracy in patients with days to weeks of life. Objective: We aimed to evaluate and compare the accuracy of CPS by attending physicians, residents, and nurses in an acute palliative care unit at a medical center. Methods: This was a 1-year prospective cohort study. Survival prediction was made within 3 days after patients' admission and re-evaluated every week until patients' discharge or death. Associated factors of accurate survival predictions were also explored by multivariate logistic regression. Results: A total of 179 inpatients were recruited and 115 of them were included in this analysis. The mean age of participants was 72.9 years and the average length of actual survival was 11.5 ± 12.0 days. For patients with survival within 30 days, the medical staff tended to overestimate their life span. The predictions made by physicians and nurses showed much closer to actual survival length through repeated estimations. Patients with metastatic cancer (odds ratio: OR 2.77, 95% CI 1.23-6.22) or cognitive impairment (OR 2.39, 95% CI 1.12-5.11) had higher associations with accurate CPS. Poor performance status of ECOG (OR 1.82, 95% CI 1.09-3.02) and dysphagia (OR 2.01, 95% CI 1.07-3.77) were significant predictors for accurate CPS in patients with the survival of less than 2 weeks. Conclusions: The accuracy of CPS between different medical staff did not reveal significant differences in the study. The importance of re-evaluation for patients' survival length in clinical practice is worthy of attention.
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Neoplasias , Doente Terminal , Humanos , Idoso , Estudos Prospectivos , Prognóstico , Cuidados Paliativos , Corpo Clínico Hospitalar , Análise de SobrevidaRESUMO
Brusatol, a major quassinoid extract of Bruceae fructus, is an important bioactive component with antineoplastic capacity. Several beneficial pharmacological and biological properties of brusatol have been uncovered to date, including anti-inflammatory, anticolitis, antimalarial, and anticancer activities. To confer anticancer benefits, brusatol is reported to effectively inhibit the Nrf2-mediated antioxidant response and trigger apoptotic signaling. In this study, we investigated the regulatory mechanisms underlying apoptotic processes in brusatol-treated A549 cells in detail. Our experiments showed that brusatol induces cell death through intracellular ROS-triggered mitochondria-dependent apoptotic events and does not involve necrosis. Mechanistically, p21-activated protein kinase 2 (PAK2) was cleaved by caspase-3 to generate an activated p34 fragment involved in brusatol-induced apoptosis of A549 cells. Notably, PAK2 knockdown led to downregulation of caspase-3-mediated PAK2 activity, in turn, effectively attenuating brusatol-induced apoptosis, highlighting a crucial role of caspase-3-activated PAK2 in this process. Moreover, knockdown of PAK2 resulted in significant inhibition of c-Jun N-terminal kinase (JNK) activity in brusatol-treated A549 cells, clearly suggesting that JNK serves as a downstream substrate of caspase-3-cleaved/activated PAK2 in the apoptotic cascade. SP600125, a specific JNK inhibitor, significantly suppressed brusatol-induced JNK activity but only partially prevented apoptosis, implying that JNK serves as only one of a number of substrates for PAK2 in the brusatol-triggered apoptotic cascade. Based on the collective results, we propose a signaling cascade model for brusatol-induced apoptosis in human A549 cells involving ROS, caspases, PAK2, and JNK.
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An aerobic bacterium, designated as strain KD337-16T, was isolated from the fecal samples of a black pig. It exhibited spherical, non-motile and non−spore-forming, Gram-positive cells. KD337-16T was identified as a member of the genus Micrococcus through 16S rRNA gene sequencing, and its closest relatives were found to be Micrococcus endophyticus YIM 56238T (99.5% similarity), Micrococcus luteus NCTC 2665T (99.1%), Micrococcus yunnanensis YIM 65004T (99.1%), Micrococcus aloeverae AE-6T (99.1%), Micrococcus antarcticus T2T (98.9%), and Micrococcus flavus LW4T (98.7%). Phylogenomic trees were constructed, and strain KD337-16T was found to form its own cluster as an independent lineage of M. flavus LW4T. Between KD337-16T and its close relatives, the average nucleotide identity, average amino acid identity, and digital DNA−DNA hybridization were below the respective species delineation thresholds at 82.1−86.6%, 78.1−86.1%, and 24.4−34.9%. The major cellular fatty acids and polar lipids were anteiso-C15:0 and iso-C15:0, and DPG and PG, respectively. The predominant menaquinone was MK-8(H2). Taken together, the results indicate that strain KD337-16T is a novel species of the genus Micrococcus, for which the name Micrococcus porci sp. nov. is proposed. The type strain is KD337-16T (=BCRC 81318T = NBRC 115578T).
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Trimethylamine oxide (TMAO) originates from trimethylamine (TMA), which is oxidized in the liver by hepatic flavin-containing monooxygenases (FMO3). TMA is produced by its dietary precursors such as choline, carnitine, and phosphatidylcholine by gut microbiota. TMAO attracts attention, identified as a novel and independent risk factor for promoting obesity, atherosclerosis and cardiovascular disease (CVD), chronic kidney disease (CKD), insulin tolerance, and colon cancer. Probiotics have been considered as live microorganisms, providing benefits to their host when they are given in sufficient quantities and administered continuously. The objective of this study is to suggest a method to select potential probiotic strains to reduce the serum concentration of TMAO in mice fed with choline. In this work, we chose three lactobacilli with strong adherence capability, and fed multistrain formula (MF) to the mice challenged with choline. On days 7, 14, and day 28, it was found that the MF-containing L. amylovorus LAM1345, Lpb. plantarum LP1145, and Lim. fermentum LF33 showed a significant reduction in serum TMAO and TMA levels. For the single strains, LP1145 reduced TMAO on days 14 and 28, and strain LAM1345 reduced TMAO significantly on days 7 and day 14. For strain LF1143 from strain LF33, it showed no significant effect on TMAO and TMA. Thus, MF showed the best effect, which may be due to the additive and synergetic effect and the contribution of strain LP1145 and LAM1345. Finally, for the LAM1345 and LP1145 strains, we used molecular identification and typing methods to assure that these two strains are unique strains. The methods used for LAM 1345 were leader peptidase A (lepA) gene analysis and phylogenetic analysis, while for strain LP 1145and other strains of Lpb. plantarum subsp. plantarum sequences were compared using the whole-genome multilocus sequence typing (wgMLST) method.
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Strengthening the gut epithelial barrier is a potential strategy for management of gut microbiota-associated illnesses. Here, we demonstrate that dual-specificity phosphatase 6 (Dusp6) knockout enhances baseline colon barrier integrity and ameliorates dextran sulfate sodium (DSS)-induced colonic injury. DUSP6 mutation in Caco-2 cells enhances the epithelial feature and increases mitochondrial oxygen consumption, accompanied by altered glucose metabolism and decreased glycolysis. We find that Dusp6-knockout mice are more resistant to DSS-induced dysbiosis, and the cohousing and fecal microbiota transplantation experiments show that the gut/fecal microbiota derived from Dusp6-knockout mice also confers protection against colitis. Further culturomics and mono-colonialization experiments show that one gut microbiota member in the genus Duncaniella confers host protection from DSS-induced injury. We identify Dusp6 deficiency as beneficial for shaping the gut microbiota eubiosis necessary to protect against gut barrier-related diseases.
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Colite/microbiologia , Fosfatase 6 de Especificidade Dupla/metabolismo , Microbioma Gastrointestinal/fisiologia , Animais , Células CACO-2 , Colite/prevenção & controle , Colo/metabolismo , Sulfato de Dextrana/farmacologia , Modelos Animais de Doenças , Fosfatase 6 de Especificidade Dupla/deficiência , Fosfatase 6 de Especificidade Dupla/genética , Disbiose/metabolismo , Células Epiteliais/metabolismo , Fezes , Feminino , Humanos , Mucosa Intestinal/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Ribossômico 16S/metabolismoRESUMO
Biological and cellular interleukin-6 (IL-6)-related therapies have been used to treat severe COVID-19 pneumonia with hyperinflammatory syndrome and acute respiratory failure, which prompted further exploration of the role of IL-6 in human umbilical cord mesenchymal stem cell (hUCMSC) therapy. Peripheral blood mononuclear cells (PBMCs) were responders cocultured with hUCMSCs or exogenous IL-6. A PBMC suppression assay was used to analyze the anti-inflammatory effects via MTT assay. The IL-6 concentration in the supernatant was measured using ELISA. The correlation between the anti-inflammatory effect of hUCMSCs and IL-6 levels and the relevant roles of IL-6 and IL-6 mRNA expression was analyzed using the MetaCore functional network constructed from gene microarray data. The location of IL-6 and IL-6 receptor (IL-6R) expression was further evaluated. We reported that hUCMSCs did not initially exert any inhibitory effect on PHA-stimulated proliferation; however, a potent inhibitory effect on PHA-stimulated proliferation was observed, and the IL-6 concentration reached approximately 1000 ng/mL after 72 hours. Exogenous 1000 ng/mL IL-6 inhibited PHA-stimulated inflammation but less so than hUCMSCs. The inhibitory effects of hUCMSCs on PHA-stimulated PBMCs disappeared after adding an IL-6 neutralizing antibody or pretreatment with tocilizumab (TCZ), an IL-6R antagonist. hUCMSCs exert excellent anti-inflammatory effects by inducing higher IL-6 levels, which is different from TCZ. High concentration of IL-6 cytokine secretion plays an important role in the anti-inflammatory effect of hUCMSC therapy. Initial hUCMSC therapy, followed by TCZ, seems to optimize the therapeutic potential to treat COVID-19-related acute respiratory distress syndrome (ARDS).
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Anticorpos Monoclonais Humanizados/uso terapêutico , COVID-19/complicações , Interleucina-6/biossíntese , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Síndrome do Desconforto Respiratório/terapia , SARS-CoV-2 , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Neutralizantes/imunologia , Células Cultivadas , Técnicas de Cocultura , Terapia Combinada , DNA Complementar/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação , Interleucina-6/genética , Interleucina-6/farmacologia , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Fito-Hemaglutininas/farmacologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptores de Interleucina-6/antagonistas & inibidores , Receptores de Interleucina-6/biossíntese , Receptores de Interleucina-6/genética , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/etiologia , Cordão Umbilical/citologiaRESUMO
Target enrichment is becoming increasingly popular for phylogenomic studies. Although baits for enrichment are typically designed to target single-copy genes, paralogs are often recovered with increased sequencing depth, sometimes from a significant proportion of loci, especially in groups experiencing whole-genome duplication (WGD) events. Common approaches for processing paralogs in target enrichment data sets include random selection, manual pruning, and mainly, the removal of entire genes that show any evidence of paralogy. These approaches are prone to errors in orthology inference or removing large numbers of genes. By removing entire genes, valuable information that could be used to detect and place WGD events is discarded. Here, we used an automated approach for orthology inference in a target enrichment data set of 68 species of Alchemilla s.l. (Rosaceae), a widely distributed clade of plants primarily from temperate climate regions. Previous molecular phylogenetic studies and chromosome numbers both suggested ancient WGDs in the group. However, both the phylogenetic location and putative parental lineages of these WGD events remain unknown. By taking paralogs into consideration and inferring orthologs from target enrichment data, we identified four nodes in the backbone of Alchemilla s.l. with an elevated proportion of gene duplication. Furthermore, using a gene-tree reconciliation approach, we established the autopolyploid origin of the entire Alchemilla s.l. and the nested allopolyploid origin of four major clades within the group. Here, we showed the utility of automated tree-based orthology inference methods, previously designed for genomic or transcriptomic data sets, to study complex scenarios of polyploidy and reticulate evolution from target enrichment data sets.[Alchemilla; allopolyploidy; autopolyploidy; gene tree discordance; orthology inference; paralogs; Rosaceae; target enrichment; whole genome duplication.].
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Alchemilla , Rosaceae , Evolução Molecular , Duplicação Gênica , Filogenia , PoliploidiaRESUMO
Biodiversity is not evenly distributed among related groups, raising questions about the factors contributing to such disparities. The sunflower family (Asteraceae, >26,000 species) is among the largest and most diverse plant families, but its species diversity is concentrated in a few subfamilies, providing an opportunity to study the factors affecting biodiversity. Phylotranscriptomic analyses here of 244 transcriptomes and genomes produced a phylogeny with strong support for the monophyly of Asteraceae and the monophyly of most subfamilies and tribes. This phylogeny provides a reference for detecting changes in diversification rates and possible factors affecting Asteraceae diversity, which include global climate shifts, whole-genome duplications (WGDs), and morphological evolution. The origin of Asteraceae was estimated at ~83 Mya, with most subfamilies having diverged before the Cretaceous-Paleocene boundary. Phylotranscriptomic analyses supported the existence of 41 WGDs in Asteraceae. Changes to herbaceousness and capitulescence with multiple flower-like capitula, often with distinct florets and scaly pappus/receptacular bracts, are associated with multiple upshifts in diversification rate. WGDs might have contributed to the survival of early Asteraceae by providing new genetic materials to support morphological transitions. The resulting competitive advantage for adapting to different niches would have increased biodiversity in Asteraceae.
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Asteraceae/genética , Biodiversidade , Evolução Molecular , Duplicação Gênica/genética , Genoma de Planta/genética , Filogenia , Poliploidia , Transcriptoma/genéticaRESUMO
Fabaceae are the third largest angiosperm family, with 765 genera and â¼19 500 species. They are important both economically and ecologically, and global Fabaceae crops are intensively studied in part for their nitrogen-fixing ability. However, resolution of the intrasubfamilial Fabaceae phylogeny and divergence times has remained elusive, precluding a reconstruction of the evolutionary history of symbiotic nitrogen fixation in Fabaceae. Here, we report a highly resolved phylogeny using >1500 nuclear genes from newly sequenced transcriptomes and genomes of 391 species, along with other datasets, for a total of 463 legumes spanning all 6 subfamilies and 333 of 765 genera. The subfamilies are maximally supported as monophyletic. The clade comprising subfamilies Cercidoideae and Detarioideae is sister to the remaining legumes, and Duparquetioideae and Dialioideae are successive sisters to the clade of Papilionoideae and Caesalpinioideae. Molecular clock estimation revealed an early radiation of subfamilies near the K/Pg boundary, marked by mass extinction, and subsequent divergence of most tribe-level clades within â¼15 million years. Phylogenomic analyses of thousands of gene families support 28 proposed putative whole-genome duplication/whole-genome triplication events across Fabaceae, including those at the ancestors of Fabaceae and five of the subfamilies, and further analyses supported the Fabaceae ancestral polyploidy. The evolution of rhizobial nitrogen-fixing nodulation in Fabaceae was probed by ancestral character reconstruction and phylogenetic analyses of related gene families and the results support the hypotheses of one or two switch(es) to rhizobial nodulation followed by multiple losses. Collectively, these results provide a foundation for further morphological and functional evolutionary analyses across Fabaceae.
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Fabaceae/genética , Fixação de Nitrogênio/genética , Rhizobium/genética , Simbiose/genética , Evolução Molecular , Filogenia , PoliploidiaRESUMO
Previous studies have shown that berberine, an isoquinoline alkaloid isolated from several traditional Chinese herbal medicines, suppresses growth and induces apoptosis in some tumor cell lines. It has also been shown that berberine possesses anti-atherosclerosis and antioxidant activities in hyperlipidemic model rats. Our previous study in mice found that berberine causes harmful effects on preimplantation and postimplantation embryonic development, both in vitro and in vivo, by triggering reactive oxygen species (ROS)-mediated apoptotic cascades in mouse blastocysts. In the current investigation, we further showed that berberine treatment has distinct dose-dependent effects on oocyte maturation and subsequent development. Preincubation of oocytes with 2.5 µM berberine significantly enhanced maturation and in vitro fertilization (IVF) rates, with subsequent beneficial effects on embryonic development. In contrast, preincubation with 10 µM berberine negatively impacted mouse oocyte maturation, decreased IVF rates and impaired subsequent embryonic development. Similar dose-dependent effects were also demonstrated in vivo. Specifically, intravenous injection of berberine significantly enhanced mouse oocyte maturation, IVF rate and early-stage embryo development after fertilization at a dose of 1 mg/kg body weight but significantly impaired oocyte maturation and IVF rates and caused harmful effects on early embryonic development at a dose of 5 mg/kg. Mechanistically, we found that berberine enhanced intracellular ROS production and apoptosis of oocytes at a concentration of 10 µM but actually significantly decreased total intracellular ROS content and had no apoptotic effect at a concentration of 2.5 µM. Moreover, pretreatment of oocytes with Ac-DEVD-cho, a caspase-3-specific inhibitor, effectively blocked berberine-induced negative impacts on oocyte maturation, fertilization and subsequent development. Collectively, these findings establish the dose-dependent beneficial versus deleterious effects of berberine and suggest that the mechanism underlying the deleterious effects of berberine involves a caspase-3-dependent apoptotic process acting downstream of an increase in intracellular ROS levels.
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Asterids are one of the most successful angiosperm lineages, exhibiting extensive morphological diversity and including a number of important crops. Despite their biological prominence and value to humans, the deep asterid phylogeny has not been fully resolved, and the evolutionary landscape underlying their radiation remains unknown. To resolve the asterid phylogeny, we sequenced 213 transcriptomes/genomes and combined them with other data sets, representing all accepted orders and nearly all families of asterids. We show fully supported monophyly of asterids, Berberidopsidales as sister to asterids, monophyly of all orders except Icacinales, Aquifoliales, and Bruniales, and monophyly of all families except Icacinaceae and Ehretiaceae. Novel taxon placements benefited from the expanded sampling with living collections from botanical gardens, resolving hitherto uncertain relationships. The remaining ambiguous placements here are likely due to limited sampling and could be addressed in the future with relevant additional taxa. Using our well-resolved phylogeny as reference, divergence time estimates support an Aptian (Early Cretaceous) origin of asterids and the origin of all orders before the Cretaceous-Paleogene boundary. Ancestral state reconstruction at the family level suggests that the asterid ancestor was a woody terrestrial plant with simple leaves, bisexual, and actinomorphic flowers with free petals and free anthers, a superior ovary with a style, and drupaceous fruits. Whole-genome duplication (WGD) analyses provide strong evidence for 33 WGDs in asterids and one in Berberidopsidales, including four suprafamilial and seven familial/subfamilial WGDs. Our results advance the understanding of asterid phylogeny and provide numerous novel evolutionary insights into their diversification and morphological evolution.
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Duplicação Cromossômica , Magnoliopsida/genética , Filogenia , Poliploidia , Flores/anatomia & histologia , Magnoliopsida/anatomia & histologia , Magnoliopsida/metabolismo , TranscriptomaRESUMO
The ability of climbing plants to grow upward along others to reach the canopy for photosynthesis is hypothesized as a key innovation in flowering plants. Most members of the Cucurbitaceae, a family containing â¼1000 species and many important crops, are climbers and have characteristic tendrils and pepo fruits. Here, we present 127 newly sequenced transcriptomes and genomes along with other datasets for a total of 136 cucurbits representing all tribes to establish a robust Cucurbitaceae phylogeny containing eight highly resolved major clades. We analyzed whole-genome duplication, diversification dynamics, and ancestral morphologies, and found that after early genome duplication event(s), a burst of diversification and morphological innovations in flower, fruit, and root characters occurred under the climate optimum in the Early Eocene. Species radiation during the Mid-Eocene Climatic Optimum also coincided with several morphological changes shared by 80% of cucurbits. We found that the cucurbit-specific tendril identity gene TEN originated from a paleo-polyploidization event at the origin of the family. Our results support the hypothesis that cucurbit diversifications were probably driven by increased genetic diversity following polyploidizations and by trait morphological innovations under paleo-climate upheavals. Our study provides a phylogenetic framework and new insights into morphological and genomic changes underlying the adaptive evolution of Cucurbitaceae.
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Evolução Biológica , Cucurbitaceae/genética , Duplicação Gênica , Genoma de Planta , Transcriptoma/genética , Conjuntos de Dados como Assunto , FilogeniaRESUMO
Ferns, the second largest group of vascular plants, originated ~400 million years ago (Mya). They became dominant in the ancient Earth landscape before the angiosperms and are still important in current ecosystems. Many ferns have exceptionally high chromosome numbers, possibly resulting from whole-genome duplications (WGDs). However, WGDs have not been investigated molecularly across fern diversity. Here we detected and dated fern WGDs using a phylogenomic approach and by calculating synonymous substitution rates (Ks). We also investigated a possible correlation between proposed WGDs and shifts in species diversification rates. We identified 19 WGDs: three ancient events along the fern phylogenetic backbone that are shared by 66%-97% of extant ferns, with additional lineage-specific WGDs for eight orders, providing strong evidence for recurring genome duplications across fern evolutionary history. We also observed similar Ks peak values for more than half of these WGDs, with multiple WGDs occurring close to the Cretaceous (~145-66 Mya). Despite the repeated WGD events, the biodiversity of ferns declined during the Cretaceous, implying that other factors probably contributed to the floristic turnover from ferns to angiosperms. This study provides molecular evidence for recurring WGDs in ferns and offers important clues to the genomic evolutionary history of ferns.
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Evolução Molecular , Gleiquênias/genética , Duplicação Gênica , Genoma de Planta , Adaptação Fisiológica/genética , Biodiversidade , Clima , Fósseis , Genes Duplicados , Modelos Lineares , Paleontologia , Filogenia , Poliploidia , Especificidade da EspécieRESUMO
Micrococcus aloeverae,Micrococcus endophyticus, Micrococcus luteus and Micrococcus yunnanensis are phenotypically and genotypically closely related, and together comprise the M. luteus group. In this study, the taxonomic relationships among Micrococcus aloeverae, M. luteus and M. yunnanensis were re-evaluated by using polyphasic approaches. The similarity values of the concatenated housekeeping gene (gyrB, recA and rpoB) sequences shared by the type strains of M. aloeverae, M. luteus and M. yunnanensis ranged from 98.3 to 99.4â%. The average nucleotide identity, average amino acid identity and digital DNAâDNA hybridization values among these three taxa were greater (97.1â98.1â%, 96.8â98.1â% and 75.0â83.5â%, respectively) than the thresholds for bacterial species delineation, indicating that they belong to the same species, whereas those for M. endophyticus were clearly lower than the thresholds. In addition, phenotypic and chemotaxonomic characterization results also support the synonymy of these three taxa. Therefore, we propose that M. aloeverae and M. yunnanensis should be reclassified as later heterotypic synonyms of M. luteus.
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Micrococcus luteus/classificação , Micrococcus/classificação , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
BACKGROUND: Dendritic cells (DCs) that are derived from hematopoietic stem cells (HSCs) are the most potent antigen-presenting cells and play a pivotal role in initiating the immune response. Hence, large-scale production and direct induction of functional DCs ex vivo from HSCs are crucial to HSC research and clinical potential, such as vaccines for cancer and immune therapy. METHODS: In a previous study, we developed a serum-free HSC expansion system (SF-HSC medium) to expand large numbers of primitive HSCs ex vivo. Herein, a DC induction and expansion medium (DC medium) was proposed to further generate large numbers of functional DCs from serum-free expanded HSCs, which were developed and optimized by factorial design and the steepest ascent method. RESULTS: The DC medium is composed of effective basal medium (Iscove's modified Dulbecco's medium [IMDM]) and cytokines (2.9 ng/mL stem cell factor [SCF], 2.1 ng/mL Flt-3 ligand, 3.6 ng/mL interleukin [IL]-1ß, 19.3 ng/mL granulocyte-macrophage colony-stimulating factor [GM-CSF] and 20.0 ng/mL tumor necrosis factor-α [TNF-α]). After 10-day culture in DC medium, the maximum fold expansion for accumulated CD1a+CD11c+ DCs was more than 4000-fold, and the induced DCs were characterized and confirmed by analysis of growth kinetics, surface antigen expression, endocytosis ability, mixed lymphocyte reaction, specific cytokine secretion and lipopolysaccharide stimulation. DISCUSSION: In conclusion, the combination of DC medium and SF-HSC medium can efficiently induce and expand a large amount of functional DCs from a small scale of HSCs and might be a promising source of DCs for vaccine and immune therapy in the near future.
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Técnicas de Cultura de Células/métodos , Meios de Cultura Livres de Soro/farmacologia , Células Dendríticas/citologia , Células-Tronco Hematopoéticas/citologia , Antígenos CD34/metabolismo , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/fisiologia , Endocitose , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/fisiologia , Humanos , Lipopolissacarídeos/farmacologia , Teste de Cultura Mista de Linfócitos , Fator de Células-Tronco/farmacologiaRESUMO
Enniatins are mycotoxins of Fusarium fungi that naturally exist as mixtures of cyclic depsipeptides. Previous reports have documented hazardous effects of enniatins on cells, such as apoptosis. However, their effects on pre- and post-implantation embryonic development require further clarification. Here, we showed for the first time that enniatin B1 (ENN B1) exerts cytotoxic effects on mouse blastocyst-stage embryos and induces intracellular oxidative stress and immunotoxicity in mouse fetuses. Co-incubation of blastocysts with ENN B1 triggered significant apoptosis and led to a decrease in total cell number predominantly through loss of inner cell mass. In addition, ENN B1 appeared to exert hazardous effects on pre and postimplantation embryo development potential in an in vitro development assay. Treatment of blastocysts with 1-10 µM ENN B1 led to increased resorption of post-implantation embryos and decreased fetal weight in the embryo transfer assay in a dose-dependent manner. Importantly, in an in vivo model, intravenous injection with ENN B1 (1, 3, and 5 mg/kg body weight/d) for 4 days resulted in apoptosis of blastocyst-stage embryos and impairment of embryonic development from the zygote to blastocyst stage, subsequent degradation of embryos, and further decrease in fetal weight. Intravenous injection with 5 mg/kg body weight/d ENN B1 additionally induced a significant increase in total reactive oxygen species (ROS) content and transcription levels of genes encoding antioxidant proteins in mouse fetal liver. Moreover, ENN B1 triggered apoptosis through ROS generation and strategies to prevent apoptotic processes effectively rescued ENN B1-mediated hazardous effects on embryonic development. Transcription levels of CXCL1, IL-1ß, and IL-8 related to innate immunity were downregulated after intravenous injection of ENN B1. These results collectively highlight the potential of ENN B1 to exert cytotoxic effects on embryos as well as oxidative stress and immunotoxicity during mouse embryo development.
Assuntos
Blastocisto/efeitos dos fármacos , Blastocisto/imunologia , Citotoxicidade Imunológica/efeitos dos fármacos , Depsipeptídeos/toxicidade , Desenvolvimento Embrionário/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Blastocisto/citologia , Depsipeptídeos/farmacologia , Embrião de Mamíferos , Desenvolvimento Embrionário/imunologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Micotoxinas/farmacologia , Micotoxinas/toxicidade , Gravidez , Espécies Reativas de Oxigênio/metabolismoRESUMO
Silver nanoparticles (AgNPs) are antibacterial materials widely used in numerous products and medical supplies. Previously, we showed that AgNPs trigger apoptotic processes in mouse blastocysts, leading to a decrease in cell viability and impairment of preimplantation and postimplantation embryonic development in vitro and in vivo. In the present study, we further investigated the hazardous effects of AgNPs on mouse oocyte maturation, in vitro fertilization (IVF), and subsequent preimplantation and postimplantation development in vitro and in vivo. Data from in vitro experiments revealed that AgNPs impair mouse oocyte maturation, decrease IVF rates, and induce injury effects on subsequent embryonic development to a significant extent. In an animal model, intravenous injection of AgNPs (5 mg/kg body weight) led to a significant decrease in mouse oocyte maturation and IVF concomitant with impairment of early embryonic development in vivo. Importantly, pretreatment with N-acetylcysteine effectively prevented AgNP-triggered reactive oxygen species (ROS) production and apoptosis, clearly suggesting a critical role of ROS as an upstream initiator or key regulator of AgNP-induced hazardous effects on oocyte maturation and sequent embryonic development. Furthermore, preincubation of oocytes with Ac-DEVD-cho, a caspase-3-specific inhibitor, effectively prevented hazardous effects, highlighting the potential involvement of caspase-dependent apoptotic signaling cascades in AgNP-mediated events. Expression levels of p53 and p21 of blastocysts were upregulated upon preincubation of mouse oocytes with AgNPs. Our collective results imply that cell apoptosis in mouse blastocysts derived from the AgNP-pretreated oocytes via intracellular ROS generation, which is further mediated through p53-, p21-, and caspase-3-dependent regulatory mechanisms.
Assuntos
Apoptose/efeitos dos fármacos , Desenvolvimento Fetal/efeitos dos fármacos , Nanopartículas Metálicas/química , Oócitos/efeitos dos fármacos , Prata/química , Animais , Blastocisto/efeitos dos fármacos , Blastocisto/metabolismo , Caspase 3/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/antagonistas & inibidores , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Fertilização in vitro/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Camundongos , Camundongos Endogâmicos ICR , Gravidez , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima/efeitos dos fármacosRESUMO
Ferns account for 80% of nonflowering vascular plant species and are the sister lineage of seed plants. Recent molecular phylogenetics have greatly advanced understanding of fern tree of life, but relationships among some major lineages remain unclear. To better resolve the phylogenetic relationships of ferns, we generated transcriptomes from 125 ferns and two lycophytes, with three additional public datasets, to represent all 11 orders and 85% of families of ferns. Our nuclear phylogeny provides strong supports for the monophyly of all four subclasses and nearly all orders and families, and for relationships among these lineages. The only exception is Gleicheniales, which was highly supported as being paraphyletic with Dipteridaceae sister to a clade with Gleicheniaceaeâ¯+â¯Hymenophyllales. In addition, new and strongly supported phylogenetic relationships are found for suborders and families in Polypodiales. We provide the first dated fern phylogenomic tree using many nuclear genes from a large majority of families, with an estimate for separation of the ancestors of ferns and seed plants in early Devonian at â¼400 Mya and subsequent gradual divergences of fern orders from â¼380 to 200 Mya. Moreover, the newly obtained fern phylogeny provides a framework for gene family analyses, which indicate that the vast majority of transcription factor families found in seed plants were already present in the common ancestor of extant vascular plants. In addition, fern transcription factor genes show similar duplication patterns to those in seed plants, with some showing stable copy number and others displaying independent expansions in both ferns and seed plants. This study provides a robust phylogenetic and gene family evolution framework, as well as rich molecular resources for understanding the morphological and functional evolution in ferns.