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1.
Nature ; 600(7887): 54-58, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34666338

RESUMO

The Moon has a magmatic and thermal history that is distinct from that of the terrestrial planets1. Radioisotope dating of lunar samples suggests that most lunar basaltic magmatism ceased by around 2.9-2.8 billion years ago (Ga)2,3, although younger basalts between 3 Ga and 1 Ga have been suggested by crater-counting chronology, which has large uncertainties owing to the lack of returned samples for calibration4,5. Here we report a precise lead-lead age of 2,030 ± 4 million years ago for basalt clasts returned by the Chang'e-5 mission, and a 238U/204Pb ratio (µ value)6 of about 680 for a source that evolved through two stages of differentiation. This is the youngest crystallization age reported so far for lunar basalts by radiometric dating, extending the duration of lunar volcanism by approximately 800-900 million years. The µ value of the Chang'e-5 basalt mantle source is within the range of low-titanium and high-titanium basalts from Apollo sites (µ value of about 300-1,000), but notably lower than those of potassium, rare-earth elements and phosphorus (KREEP) and high-aluminium basalts7 (µ value of about 2,600-3,700), indicating that the Chang'e-5 basalts were produced by melting of a KREEP-poor source. This age provides a pivotal calibration point for crater-counting chronology in the inner Solar System and provides insight on the volcanic and thermal history of the Moon.

2.
J Proteome Res ; 23(6): 2195-2205, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38661673

RESUMO

The programmed death-ligand 1 (PD-L1) is a key mediator of immunosuppression in the tumor microenvironment. The expression of PD-L1 in cancer cells is useful for the clinical determination of an immune checkpoint blockade (ICB). However, the regulatory mechanism of the PD-L1 abundance remains incompletely understood. Here, we integrated the proteomics of 52 patients with solid tumors and examined immune cell infiltration to reveal PD-L1-related regulatory modules. Wiskott-Aldrich syndrome protein (WASP) was identified as a potential regulator of PD-L1 transcription. In two independent cohorts containing 164 cancer patients, WASP expression was significantly associated with PD-L1. High WASP expression contributed to immunosuppressive cell composition, including cells positive for immune checkpoints (PD1, CTLA4, TIGIT, and TIM3), FoxP3+ Treg cells, and CD163+ tumor-associated macrophages. Overexpression of WASP increased, whereas knockdown of WASP decreased the protein level of PD-L1 in cancer cells without alteration of PD-L1 protein stability. The WASP-mediated cell migration and invasion were markedly attenuated by the silence of PD-L1. Collectively, our data suggest that WASP is a potential regulator of PD-L1 and the WASP/PD-L1 axis is responsible for cell migration and an immunosuppressive microenvironment.


Assuntos
Antígeno B7-H1 , Neoplasias , Proteômica , Microambiente Tumoral , Proteína da Síndrome de Wiskott-Aldrich , Humanos , Antígeno B7-H1/metabolismo , Antígeno B7-H1/genética , Proteômica/métodos , Proteína da Síndrome de Wiskott-Aldrich/metabolismo , Proteína da Síndrome de Wiskott-Aldrich/genética , Neoplasias/metabolismo , Neoplasias/genética , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral
3.
Environ Sci Technol ; 58(10): 4545-4557, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38386019

RESUMO

Global warming has caused the degradation of coral reefs around the world. While stress-tolerant corals have demonstrated the ability to acclimatize to ocean warming, it remains unclear whether they can sustain their thermal resilience when superimposed with other coastal environmental stressors. We report the combined impacts of a photosystem II (PSII) herbicide, prometryn, and ocean warming on the stress-tolerant coral Galaxea fascicularis through physiological and omics analyses. The results demonstrate that the heat-stress-induced inhibition of photosynthetic efficiency in G. fascicularis is exacerbated in the presence of prometryn. Transcriptomics and metabolomics analyses indicate that the prometryn exposure may overwhelm the photosystem repair mechanism in stress-tolerant corals, thereby compromising their capacity for thermal acclimation. Moreover, prometryn might amplify the adverse effects of heat stress on key energy and nutrient metabolism pathways and induce a stronger response to oxidative stress in stress-tolerant corals. The findings indicate that the presence of prometryn at environmentally relevant concentrations would render corals more susceptible to heat stress and exacerbate the breakdown of coral Symbiodiniaceae symbiosis. The present study provides valuable insights into the necessity of prioritizing PSII herbicide pollution reduction in coral reef protection efforts while mitigating the effects of climate change.


Assuntos
Antozoários , Herbicidas , Animais , Antozoários/fisiologia , Prometrina , Recifes de Corais , Oceanos e Mares , Simbiose
4.
Proc Natl Acad Sci U S A ; 118(45)2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34725149

RESUMO

The Toba volcanic system in Indonesia has produced two of the largest eruptions (>2,000 km3 dense-rock equivalent [DRE] each) on Earth since the Quaternary. U-Pb crystallization ages of zircon span a period of ∼600 ky before each eruptive event, and in the run-up to each eruption, the mean and variance of the zircons' U content decrease. To quantify the process of accumulation of eruptible magma underneath the Toba caldera, we integrated these observations with thermal and geochemical modeling. We show that caldera-forming eruptions at Toba are the result of progressive thermal maturation of the upper crustal magma reservoir, which grows and chemically homogenizes, by sustained magma influx at average volumetric rates between 0.008 and 0.01 km3/y over the past 2.2 My. Protracted thermal pulses related to magma-recharge events prime the system for eruption without necessarily requiring an increased magma-recharge rate before the two supereruptions. If the rate of magma input was maintained since the last supereruption of Toba at 75 ka, eruptible magma is currently accumulating at a minimum rate of ∼4.2 km3 per millennium, and the current estimate of the total volume of potentially eruptible magma available today is a minimum of ∼315 km3 Our approach to evaluate magma flux and the rate of eruptible magma accumulation is applicable to other volcanic systems capable of producing supereruptions and thereby could help in assessing the potential of active volcanic systems to feed supereruptions.

5.
Int J Syst Evol Microbiol ; 73(10)2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37831063

RESUMO

Light yellowish-white colonies of a bacterial strain, designated LNNU 24178T, were isolated from the rhizosphere soil of halophyte Suaeda aralocaspica (Bunge) Freitag and Schütze grown at Shihezi district, Xinjiang, PR China. Cells were Gram-stain-negative, non-flagellum-forming, rod-shaped and non-motile. The results of phylogenetic analysis based on the 16S rRNA gene sequence indicated that LNNU 24178T represented a member of the genus Luteimonas and shared the highest sequence similarity with Luteimonas yindakuii CGMCC 1.13927T (97.1 %) and lower sequence similarity (< 97.0 %) to other known species. The genomic DNA G+C content of LNNU 24178T was 68.8 %. The average nucleotide identity (ANI) values between LNNU 24178T and Luteimonas yindakuii CGMCC 1.13927T, Luteimonas mephitis DSM 12574T, Luteimonas arsenica 26-35T and Luteimonas huabeiensis HB2T were 78.7, 78.6, 78.4 and 80.0 %, respectively. The digital DNA-DNA hybridisation (dDDH) values between LNNU 24178T and L. yindakuii CGMCC 1.13927T, L. mephitis DSM 12574T, L. arsenica 26-35T and L. huabeiensis HB2T were 22.0, 22.3, 22.2 and 23.5 %, respectively. The respiratory quinone detected in LNNU 24178T was ubiquinone-8 (Q-8). The major fatty acids (> 5.0 %) of LNNU 24178T were identified as iso-C15 : 0 (33.9 %), iso-C17 : 0 (8.7 %), iso-C11 : 0 (6.2 %), iso-C16 : 0 (5.7 %), C16 : 0 (5.3 %) and summed feature 9 (iso-C17 : 1ω9c/10-methyl C16 : 0) (21.1 %). The major polar lipids of LNNU 24178T were diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylethanolamine (PE), one unidentified phospholipid (PL), one unidentified glycolipid (GL) and three unidentified lipids. According to the data obtained from phenotypic, chemotaxonomic and phylogenetic analyses, strain LNNU 24178T represents a novel species of the genus Luteimonas, for which the name Luteimonas suaedae sp. nov. is proposed, with LNNU 24178T (= CGMCC 1.17331T= KCTC 62251T) as the type strain.


Assuntos
Ácidos Graxos , Rizosfera , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Composição de Bases , Técnicas de Tipagem Bacteriana , Análise de Sequência de DNA , Fosfolipídeos
6.
Oral Dis ; 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37249063

RESUMO

OBJECTIVES: To reveal the effect and mechanism of methyltransferase-like 3 (METTL3) on cancer stem cells (CSCs) of head and neck squamous cell carcinoma (HNSCC). MATERIALS AND METHODS: First, we analyzed 14-HNSCC-patients' scRNA-seq dataset and TCGA dataset of HNSCC. Then, Mettl3 knockout or overexpression mice models were studied via tracing and staining technologies. In addition, we took flow cytometry sorting and sphere formation assays to observe tumorigenicity and used cell transfection and western blotting to verify target protein expression levels. Furthermore, methylated RNA immunoprecipitation sequencing (MeRIP-seq) and MeRIP-quantitative real-time PCR (MeRIP-qPCR) were taken to identify the mechanism of Mettl3 regulating Bmi1+ CSCs in HNSCC. RESULTS: Due to SOX4 transcriptional regulation, METTL3 regulated the malignant behavior of BMI1+ HNSCC stem cells through cell division pathway. The progression and malignancy of HNSCC were decreased after Mettl3 knocked-out, while increased after Mettl3 knocked-in in Bmi1+ CSCs in vivo. Knockdown of Mettl3 inhibited stemness properties of CSCs in vitro. Mechanically, Mettl3 mediated the m6 A modification of ALDH1A3 and ALDH7A1 mRNA in Bmi1+ HNSCC CSCs. CONCLUSION: Regulated by SOX4, METTL3-mediated ALDH m6 A methylation regulates the malignant behavior of BMI1+ HNSCC CSCs through cell division pathway.

7.
J Plant Res ; 136(5): 631-641, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37202494

RESUMO

Environmental conditions during seed development and maturation can affect seed traits and germination behavior, yet systematic research on the effects of seed maturation time on seed traits, germination behavior and seedling emergence of cleistogamy plants is lacking. Here, we determined the difference in phenotypic characteristics of CH and CL (namely CL1, CL2 and CL3 based on maturation time, respectively) fruits/seeds that were collected from Viola prionantha Bunge, a cleistogamous perennial plant, and evaluated the effects of various environmental factors on seed germination and seedling emergence. The fruit mass, width, seed number per fruit and mean seed mass of CL1 and CL3 were greater than that of CH and CL2, while seed setting of CH was lower than that of CL1, CL2 and CL3. Germination of CH, CL1, CL2, and CL3 seeds was < 10% in the dark at 15/5 and 20/10 â„ƒ, whereas germination (0%-99.2%) of CH, CL1, CL2, and CL3 seeds changed significantly under light conditions. In contrast, more than 71% (from 71.7 to 94.2%) germination of both CH, CL1, CL2 and CL3 seeds occurred under both light/dark conditions and continuous darkness at 30/20 â„ƒ. Germination of CH, CL1, CL2 and CL3 seeds was sensitive to osmotic potential, but CL1 seeds were more resistant to osmotic stress, compared with CH, CL2 and CL3. Seedling emergence of CH seeds was more than 67% (from 67.8 to 73.3%) at a burial depth of 0 cm-2 cm, while all types of CL seeds were below 15% at a burial depth of 2 cm. Information gathered from this study indicates that CH and CL seeds of V. prionantha were different in fruit size, seed mass, thermoperiod and photoperiod sensitivity, osmotic potential tolerance and seedling emergence, especially, maturation time significantly affect phenotypic characteristics and germination behavior of CL seeds matured at different periods. These results indicate that V. prionantha adapts to unpredictable environmental conditions by developing a variety of adaptation strategies, and ensures the survival and reproduction of the populations.


Assuntos
Plântula , Viola , Germinação , Sementes , Reprodução
8.
Proc Natl Acad Sci U S A ; 117(25): 14299-14305, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32513701

RESUMO

The Lower Cretaceous Huajiying Formation of the Sichakou Basin in northern Hebei Province, northern China contains key vertebrate taxa of the early Jehol Biota, e.g., Protopteryx fengningensis, Archaeornithura meemannae, Peipiaosteus fengningensis, and Eoconfuciusornis zhengi This formation arguably documents the second-oldest bird-bearing horizon, producing the oldest fossil records of the two major Mesozoic avian groups Enantiornithes and Ornithuromorpha. Hence, precisely determining the depositional ages of the Huajiying Formation would advance our understanding of the evolutionary history of the Jehol Biota. Here we present secondary ion mass spectrometry (SIMS) U-Pb zircon analysis results of eight interbedded tuff/tuffaceous sandstone samples from the Huajiying Formation. Our findings, combined with previous radiometric dates, suggest that the oldest enantiornithine and ornithuromorph birds in the Jehol Biota are ∼129-131 Ma, and that the Jehol Biota most likely first appeared at ∼135 Ma. This expands the biota's temporal distribution from late Valanginian to middle Aptian with a time span of about 15 My.


Assuntos
Biota , Aves/classificação , Chumbo/química , Silicatos/química , Zircônio/química , Animais , Evolução Biológica , China , Fósseis , Geologia , Filogenia , Espectrometria de Massa de Íon Secundário
9.
Anal Chem ; 94(22): 7944-7951, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35616317

RESUMO

High-quality oxygen isotope analysis of composition-variable minerals (e.g., ubiquitous carbonates) using secondary ion mass spectrometry (SIMS) is extremely challenging. The classical off-line procedure, which requires additional electron probe microanalyzer (EPMA) chemical compositions for calibrating instrumental mass fractionation (IMF), is inherently inaccurate and analytically inefficient. In this study, the first accurate and paired SIMS analysis of δ18O and Fe# [molar Fe/(Mg + Fe)] in dolomite is reported. Based on five newly developed dolomite O-isotopic standards with an Fe# range of 0.01-0.35 obtained by SIMS, a novel accurate and rapid online matrix effect calibration method for dolomite O-isotope analysis was developed using concurrent SIMS 18O-16O-56Fe16O-24Mg16O measurements without additional chemical electron probe microanalysis. A logistic equation was proposed as the best-fit curve to represent the δ18O matrix effect based on the 56Fe16O/24Mg16O ratios. For CTD-4 carbonatitic dolomite with variable Fe# but homogeneous oxygen isotopes, the off-line method exhibited highly variable apparent δ18O values in the range of 5.74-10.11‰. The online method yielded a homogeneous δ18O value of 7.94 ± 0.34‰ (2SD, n = 40), which is comparable with that of bulk analysis (7.94 ± 0.20‰; 2SD). Comprehensive analyses validated the online method as the best strategy for performing accurate δ18O analysis of samples with highly heterogeneous compositions. Based on its accuracy, simplicity, and economic feasibility, this method has potential applications in the analysis of composition-complex dolomites, detrital dolomites, and other precious terrestrial and extraterrestrial materials.


Assuntos
Carbonato de Cálcio , Minerais , Carbonato de Cálcio/química , Calibragem , Magnésio , Isótopos de Oxigênio/química
10.
Int J Mol Sci ; 23(17)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36077020

RESUMO

The NAC (NAM, ATAF1/2, and CUC2) transcription factors are one of the largest families of transcription factors in plants and play an important role in plant development and the response to adversity. In this study, we cloned a new NAC gene, SlNAC10, from the halophyte Suaeda liaotungensis K. The gene has a total length of 1584 bp including a complete ORF of 1107 bp that encodes 369 amino acids. The SlNAC10-GFP fusion protein is located in the nucleus and SlNAC10 has a transcription activation structural domain at the C-terminus. We studied the expression characteristics of SlNAC10 and found that it was highest in the leaves of S. liaotungensis and induced by drought, salt, cold, and abscisic acid (ABA). To analyze the function of SlNAC10 in plants, we obtained SlNAC10 transgenic Arabidopsis. The growth characteristics and physiological indicators of transgenic Arabidopsis were measured under salt and drought stress. The transgenic Arabidopsis showed obvious advantages in the root length and survival rate; chlorophyll fluorescence levels; and the antioxidant enzyme superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities, and the proline content was higher than that of the wild-type (WT) Arabidopsis, whereas the relative electrolyte leakage and malondialdehyde (MDA) content were lower than those of the wild-type Arabidopsis. We explored the regulatory role of SlNAC10 on proline synthesis-related enzyme genes and found that SlNAC10 binds to the AtP5CS1, AtP5CS2, and AtP5CR promoters and regulates their downstream gene transcription. To sum up, SlNAC10 as a transcription factor improves salt and drought tolerance in plants possibly by regulating proline synthesis.


Assuntos
Arabidopsis , Chenopodiaceae , Arabidopsis/metabolismo , Chenopodiaceae/genética , Chenopodiaceae/metabolismo , Secas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Prolina/metabolismo , Cloreto de Sódio/metabolismo , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
11.
Int J Mol Sci ; 23(20)2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36293085

RESUMO

Seed germination is susceptible to external environmental factors, especially salt stress. Suaeda liaotungensis is a halophyte with strong salt tolerance, and the germination rate of brown seeds under 1000 mM NaCl treatment still reached 28.9%. To explore the mechanism of salt stress response during brown seed germination in Suaeda liaotungensis, we conducted transcriptomic analysis on the dry seeds (SlD), germinated seeds under the control condition (SlG_C), and salt treatment (SlG_N). Transcriptome analysis revealed that 13314 and 755 differentially expressed genes (DEGs) from SlD vs. SlG_C and SlG_C vs. SlG_N were detected, respectively. Most DEGs were enriched in pathways related to transcription regulation and hormone signal transduction, ROS metabolism, cell wall organization or biogenesis, and carbohydrate metabolic process in two contrasting groups. Compared with the control condition, POD and CAT activity, H2O2, soluble sugar, and proline contents were increased during germinated seeds under salt stress. Furthermore, functional analysis demonstrated that overexpression of SlNAC2 significantly enhanced salt tolerance during the germination stage in Arabidopsis. These results not only revealed the tolerant mechanism of brown seed germination in response to salinity stress but also promoted the exploration and application of salt-tolerant gene resources of Suaeda liaotungensis.


Assuntos
Arabidopsis , Chenopodiaceae , Germinação/genética , Tolerância ao Sal/genética , Sementes/metabolismo , Peróxido de Hidrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Cloreto de Sódio/farmacologia , Cloreto de Sódio/metabolismo , Chenopodiaceae/genética , Chenopodiaceae/metabolismo , Arabidopsis/genética , Perfilação da Expressão Gênica , Açúcares/metabolismo , Prolina/metabolismo , Hormônios/metabolismo , Carboidratos
12.
BMC Microbiol ; 21(1): 143, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33980153

RESUMO

BACKGROUND: Seed dimorphism has been thought to be a bet-hedging strategy that helps plants survive in the disturbed environment and has been widely studied for its ecological adaptation mechanism. Many studies showed that seed-associated microorganisms play an important role in enhancing plant fitness, but information regarding endophytic bacteria associated with dimorphic seeds is limited. This study explores the influence of seed coat structure and seed phytochemical properties on the community composition and diversity of endophytic bacteria of dimorphic seeds of Suaeda glauca. In this study, we used 16S rRNA high-throughput gene sequencing method to compare the community composition and bacterial diversity between brown and black seeds of Suaeda glauca. RESULTS: A significant difference was observed in seed coat structure and phytochemical properties between brown and black seeds of S. glauca. Total 9 phyla, 13 classes, 31 orders, 53 families, 102 genera were identified in the dimorphic seeds. The dominant phyla were Proteobacteria, Firmicutes, and Actinobacteria. The results showed that seed dimorphism had little impact on the diversity and richness of endophytic bacterial communities but significantly differs in the relative abundance of the bacterial community between brown and black seeds. At the phylum level, Actinobacteria tend to be enriched significantly in brown seeds. At the genus level, Rhodococcus, Ralstonia, Pelomonas and Bradyrhizobium tend to be enriched significantly in brown seeds, while Marinilactibacillus was mainly found in black seeds. Besides, brown seeds harbored a large number of bacteria with plant-growth-promoting traits, whereas black seeds presented bacteria with enzyme activities (i.e., pectinase, cellulolytic and xylanolytic activities). CONCLUSION: The endophytic bacterial community compositions were significantly different between dimorphic seeds of Suaeda glauca, and play an important role in the ecological adaptation of dimorphic seeds by performing different biological function roles. The endophytic bacterial communities of the dimorphic seeds may be influenced mainly by the seed coat structureand partly by the seed phytochemical characteristics. These findings provide valuable information for better understanding of the ecological adaptation strategy of dimorphic seeds in the disturbed environment.


Assuntos
Bactérias/metabolismo , Chenopodiaceae/microbiologia , Endófitos/metabolismo , Plantas Tolerantes a Sal/microbiologia , Sementes/microbiologia , Bactérias/genética , Biodiversidade , RNA Ribossômico 16S/genética
13.
Artigo em Inglês | MEDLINE | ID: mdl-34542394

RESUMO

A Gram-stain-positive, non-motile and short rod-shaped actinobacterium, designated strain LNNU 22110T, was isolated from the rhizosphere soil of the halophyte Suaeda aralocaspica (Bunge) Freitag and Schütze, which collected in Xinjiang, north-west China. Growth occurred at 10-45 °C, pH 6.0-10.0 and in the presence of 0-11 % NaCl (w/v). Based on the results of 16S rRNA gene sequence phylogenetic analyses, strain LNNU 22110T belonged to the genus Ruania and had 97.5 and 95.5 % sequence similarity to Ruania alba KCTC 19413T and Ruania albidiflava CGMCC 4.3142T, respectively. The digital DNA-DNA hybridization relatedness values between strain LNNU 22110T and R. alba KCTC 19413T and R. albidiflava CGMCC 4.3142T were 23.2 and 19.9 %, respectively. The highest average nucleotide identity value between strain LNNU 22110T and its closest related strain (R. alba KCTC 19413T) was 80.2 %, much lower than the species delineation threshold of 95-96 %. The genome of strain LNNU 22110T was 4.4 Mb, with a genomic DNA G+C content of 68.4 mol%. The diagnostic diamino acids in the peptidoglycan layer of strain LNNU 22110T were lysine, alanine, glycine, glutamic acid and aspartic acid. The predominant menaquinone was MK-8(H4). The major fatty acid (>10 %) was anteiso-C15 : 0. The polar lipid profile of strain LNNU 22110T included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, diacylated phosphatidyl dimannoside, one unidentified glycolipid and two unidentified phospholipids. According to the phenotypic, phylogenetic and chemotaxonomic results, strain LNNU 22110T is considered to represent a novel species of the genus Ruania, for which the name Ruania rhizosphaerae sp. nov. is proposed. The type strain is LNNU 22110T (=KCTC 39807T=CGMCC 1.17105T).


Assuntos
Chenopodiaceae , Rizosfera , Actinobacteria , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Microbiologia do Solo
14.
Int J Syst Evol Microbiol ; 71(11)2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34846291

RESUMO

A Gram-stain-positive, non-motile and coccus-shaped bacterium, designated strain LNNU 331112T, was isolated from the composite rhizosphere soil of the halophyte Suaeda aralocaspica (Bunge) Freitag and Schütze, which was collected in Xinjiang, north-west China. Growth occurred at 10-45 °C, pH 6.0-11.0 and in the presence of 0-10 % NaCl (w/v). Phylogenetic analysis based on the 16S rRNA gene sequence suggested that strain LNNU 331112T belonged to the genus Hoyosella and showed 95.6, 95.5 and 95.4 % sequence similarities to Hoyosella altamirensis DSM 45258T, Hoyosella subflava CGMCC 4.3532T and Hoyosella rhizosphaerae CGMCC 1.15478T, respectively. The estimated digital DNA-DNA hybridization relatedness values between strain LNNU 331112T and the type strains of H. altamirensis DSM 45258T, H. subflava CGMCC 4.3532T and H. rhizosphaerae CGMCC 1.15478T were 18.9, 19.3 and 18.3 %, respectively. The average nucleotide identity values between strain LNNU 331112T and H. altamirensis DSM 45258T, H. subflava CGMCC 4.3532T and H. rhizosphaerae CGMCC 1.15478T were 72.6, 72.7 and 72.3 %, respectively. The genome sequence of strain LNNU 331112T showed 69.0-72.3 % average amino acid identity values in comparison with the related genome sequences of three validly published Hoyosella species. The genome of strain LNNU 331112T was 3.47 Mb, with a DNA G+C content of 68.4 mol%. A total of 3182 genes were identified as protein-coding in strain LNNU 331112T. Genomic analysis revealed that a number of genes involved in osmotic pressure regulation, intracellular pH homeostasis and potassium (K+) uptake protein were found in strain LNNU 331112T. The predominant menaquinones were MK-8 (44.6 %) and MK-7 (55.4 %), which differentiated strain LNNU 331112T from other three recognized Hoyosella species. Major fatty acids (>10 %) were C17 : 1 ω8c (33.8 %), C16 : 0 (23.3 %), C17 : 0 (12.8 %) and summed feature 3 (12.9 %), which also clearly separated strain LNNU 331112T from three recognized Hoyosella species. The polar lipid profile of strain LNNU 331112T included diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, one unidentified glycolipid, one unidentified phospholipid and two unidentified lipids. According to the results of phenotypic, chemotaxonomic and phylogenetic analyses, strain LNNU 331112T is considered to represent a novel species of the genus Hoyosella, for which the name Hoyosella suaedae sp. nov. is proposed. The type strain is LNNU 331112T (=KCTC 39808T=CGMCC 1.17107T=DSM 103463T).


Assuntos
Chenopodiaceae , Mycobacteriaceae/classificação , Filogenia , Rizosfera , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , Chenopodiaceae/microbiologia , China , DNA Bacteriano/genética , Ácidos Graxos/química , Mycobacteriaceae/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
15.
Mol Ther ; 28(10): 2177-2190, 2020 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-32621798

RESUMO

RNA modification plays an essential function in regulating gene expression and diverse biological processes. RNA modification enzyme methyltransferase-like 3 (METTL3) affects tumor progression by regulating the N6-methyladenosine (m6A) modification in the mRNAs of critical oncogenes or tumor suppressors, but its effect in oral squamous cell carcinoma (OSCC) remains unknown. In this study, we revealed that METTL3 was consistently upregulated in two OSCC cohorts, and high METTL3 expression was associated with poor prognosis. Functionally, cell proliferation, self-renewal, migration, and invasion ability in vitro and tumor growth and metastasis in vivo were decreased after METTL3 knockdown in OSCC cells. In contrast, the opposite results were obtained after METTL3 overexpression. In addition, the results obtained with the Mettl3 genetically modified mouse model validated the essential role of Mettl3 in chemical-induced oral carcinogenesis. In mechanism, methylated RNA immunoprecipitation sequencing (MeRIP-seq), MeRIP-quantitative real-time PCR, and luciferase reporter and mutagenesis assays identified that METTL3 mediates the m6A modification in the 3' UTR of BMI1 mRNA. METTL3 promotes BMI1 translation in OSCC under the cooperation with m6A reader IGF2BP1. Our findings revealed that METTL3 promotes OSCC proliferation and metastasis through BMI1 m6A methylation, suggesting that the METTL3-m6A-BMI1 axis may serve as a prognostic biomarker or therapeutic target in patients with OSCC.


Assuntos
Adenosina/análogos & derivados , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Metiltransferases/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Adenosina/metabolismo , Animais , Sítios de Ligação , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/metabolismo , Linhagem Celular Tumoral , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Humanos , Metilação , Metiltransferases/genética , Camundongos , Neoplasias Bucais/etiologia , Neoplasias Bucais/metabolismo , Ligação Proteica
16.
J Plant Res ; 134(5): 1105-1120, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33963939

RESUMO

NAC (NAM, ATAF1/2, CUC2) transcription factors play important roles in plant growth, development, and responses to abiotic stress. In this study, we cloned an NAC2 subfamily transcription factor gene (SlNAC7) from the halophyte Suaeda liaotungensis K., and conducted a series of studies to determine the characteristics and functions of this gene. The SlNAC7 coding region contains 1719 base pairs that encode a 573 amino acid long protein. SlNAC7 is expressed in the roots, stems, and leaves of S. liaotungensis, with the highest expression in the leaves. We found that SlNAC7 expression can be induced by drought, salt, cold, and abscisic acid. Transient expression in onion epidermal cells revealed that SlNAC7 is located in both the nucleus and cytoplasm. A transcriptional activation experiment in yeast showed that the transcriptional activation domain of SlNAC7 is located at the C terminus. When SlNAC7 was transformed into Arabidopsis under the control of a CaMV 35S promoter its overexpression was found to enhance the ability of transgenic plants to resist drought, salt, and cold stress. Moreover, these plants showed multiple changes in growth characteristics and physiological and biochemical indices in response to different stresses, as well as the upregulation of numerous stress-related genes. We have thus characterized a new halophyte-derived NAC transcription factor, SlNAC7, which can regulate plant growth and physiological and biochemical changes under adverse conditions by regulating the expression of stress-related genes, thereby enhancing plant stress resistance. SlNAC7 is a promising candidate for breeding new varieties of stress-tolerant crops.


Assuntos
Chenopodiaceae , Regulação da Expressão Gênica de Plantas , Chenopodiaceae/genética , Chenopodiaceae/metabolismo , Resposta ao Choque Frio , Secas , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
17.
Int J Syst Evol Microbiol ; 70(5): 3391-3398, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32375949

RESUMO

A novel endophytic actinobacterium, designated strain EGI 650086T, was isolated from the roots of Anabasis elatior (C.A.Mey.) Schischk. collected in Xinjiang, north-west China. The taxonomic position of the strain was investigated using a polyphasic taxonomic approach. Growth occurred at 15-40 °C, pH 6.0-8.0 and in the presence of 0-6 % NaCl (w/v). Phylogenetic analysis based on 16S rRNA gene sequence and concatenation of 22 protein marker genes revealed that strain EGI 650086T formed a monophyletic clade within the genus Amycolatopsis and shared the highest sequence similarities with Amycolatopsis nigrescens JCM 14717T (97.1 %) and Amycolatopsis sacchari DSM 44468T (97.0 %). Sequence similarities with type strains of other species of the genus Amycolatopsis were less than 97.0 %. The average nucleotide identity and DNA-DNA hybridization values between strain EGI 650086T and the reference strains were 78.1-79.8 % and 22.1-23.0 %, respectively. The genome of strain EGI 650086T was 10.9 Mb, with a DNA G+C content of 70.1 mol%. The diagnostic diamino acid in the peptidoglycan was meso-diaminopimelic acid. The major whole-cell sugars contained arabinose, galactose, glucose and ribose. The predominant menaquinones were MK-9 (H4) and MK-9 (H2). Major fatty acids were iso-C16 : 0 and summed feature 4 (iso-C17 : 1 I and/or anteiso-C17 : 1 B). The polar lipid profile of strain EGI 650086T included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, hydroxy-phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannosides, two unknown phospholipids, an unknown glycolipid and an unknown lipid. Polyphasic taxonomic characteristics indicated that strain EGI 650086T represents a novel species of the genus Amycolatopsis, for which the name Amycolatopsis anabasis sp. nov. is proposed. The type strain is EGI 650086T (=KCTC 49044T=CGMCC 4.7188T).


Assuntos
Actinobacteria/classificação , Chenopodiaceae/microbiologia , Filogenia , Raízes de Plantas/microbiologia , Actinobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Glicolipídeos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
18.
Meteorit Planet Sci ; 55(11): 2341-2359, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33510569

RESUMO

The Hamburg meteorite fell on January 16, 2018, near Hamburg, Michigan, after a fireball event widely observed in the U.S. Midwest and in Ontario, Canada. Several fragments fell onto frozen surfaces of lakes and, thanks to weather radar data, were recovered days after the fall. The studied rock fragments show no or little signs of terrestrial weathering. Here, we present the initial results from an international consortium study to describe the fall, characterize the meteorite, and probe the collision history of Hamburg. About 1 kg of recovered meteorites was initially reported. Petrology, mineral chemistry, trace element and organic chemistry, and O and Cr isotopic compositions are characteristic of H4 chondrites. Cosmic ray exposure ages based on cosmogenic 3He, 21Ne, and 38Ar are ~12 Ma, and roughly agree with each other. Noble gas data as well as the cosmogenic 10Be concentration point to a small 40-60 cm diameter meteoroid. An 40Ar-39Ar age of 4532 ± 24 Ma indicates no major impact event occurring later in its evolutionary history, consistent with data of other H4 chondrites. Microanalyses of phosphates with LA-ICPMS give an average Pb-Pb age of 4549 ± 36 Ma. This is in good agreement with the average SIMS Pb-Pb phosphate age of 4535.3 ± 9.5 Ma and U-Pb Concordia age of 4535 ± 10 Ma. The weighted average age of 4541.6 ± 9.5 Ma reflects the metamorphic phosphate crystallization age after parent body formation in the early solar system.

19.
Mediators Inflamm ; 2020: 8867760, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33424437

RESUMO

BACKGROUND: Infections are an important cause of morbidity and mortality for acute lymphoblastic leukemia (ALL). However, the reports regarding risk factors of induction-related infection are roughly unknown/limited in adult T-ALL during induction chemotherapy. METHODS: We performed a retrospective cohort study for the prevalence and risk predictors of induction-related infection among consecutive T-ALL patients (N = 97) enrolled in a PDT-ALL-LBL clinical trial. Of 97 patients with T-ALL enrolled in the trial, 46 were early T-cell precursor (ETP) ALL and 51 were non-ETP ALL. RESULTS: When compared with non-ETP, ETP ALL subtype was characterized with lower neutrophil count (1.35 × 109/L vs. 8.7 × 109/L, P < 0.001) and lower myeloid percentage in the bone marrow (13.35% vs. 35.31%, P = 0.007). Additionally, ETP ALL had longer neutropenia before diagnosis (P < 0.001), as well as during induction chemotherapy (P < 0.001). Notably, the ETP cohort experienced higher cumulative incidence of clinically documented infections (CDI; 33.33%, P = 0.001), microbiologically documented infections (MDI; 45.24%, P = 0.006), resistant infection (11.9%, P = 0.013), and mixed infection (21.43%, P = 0.003), respectively, than those of the non-ETP cohort. Furthermore, multivariable analysis revealed that T-ALL mixed infection was more likely related to chemotherapy response (OR, 0.025; 95% CI 0.127-0.64; P = 0.012) and identified myeloid percentage as a predictor associated with ETP-ALL mixed infection (OR, 0.915; 95% CI 0.843-0.993; P = 0.033), with ROC-defined cut-off value of 2.24% in ETP cohorts. CONCLUSIONS: Our data for the first time demonstrated that ETP-ALL characterized with impaired myelopoiesis were more susceptible to induction-related infection among T-ALL populations.


Assuntos
Quimioterapia de Indução/efeitos adversos , Infecções/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Células Precursoras de Linfócitos T/citologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/complicações , Adolescente , Adulto , Antineoplásicos/farmacologia , Feminino , Humanos , Imunofenotipagem , Infecções/etiologia , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células T Precursoras/diagnóstico , Prevalência , Prognóstico , Indução de Remissão , Estudos Retrospectivos , Risco , Fatores de Risco , Adulto Jovem
20.
Int J Syst Evol Microbiol ; 67(2): 282-287, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27902223

RESUMO

A novel endophytic bacterium, designated strain EGI 6500252T, was isolated from the surface-sterilized roots of a medicinal plant (Capparis spinosa L.) collected from Urumqi city, Xinjiang, north-west China. Cells were Gram-stain-positive, non-motile, aerobic, catalase- and oxidase-positive, rod-shaped and did not display spore formation. Strain EGI 6500252T grew at 10-40 °C (optimum 25-30 °C), at pH 6.0-8.0 (optimum pH 7.0) and in the presence of 0-10 % (w/v) NaCl (optimum 0-3 %). The major cellular fatty acids (>10 %) were identified as iso-C15 : 0, anteiso-C15 : 0, anteiso-C17 : 0 and summed feature 4. The predominant polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, four unknown phospholipids, one unknown glycolipid and one unknown lipid. The dominant isoprenoid quinone was menaquinone 7 (MK-7). The DNA G+C content was 39.9 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain EGI 6500252T belonged to the genus Bacillus, and exhibited a highest 16S rRNA gene sequence similarity (96.2 %) that was lower than the suggested threshold (97.0 %) for separating bacterial species. On the basis of the phylogenetic analysis, chemotaxonomic data and physiological characteristics, strain EGI 6500252T represents a novel species of the genus Bacillus, for which the name Bacillus capparidis sp. nov. is proposed. The type strain is EGI 6500252T (=CGMCC 1.12820T=KCTC 33514T).


Assuntos
Bacillus/classificação , Capparis/microbiologia , Filogenia , Raízes de Plantas/microbiologia , Bacillus/genética , Bacillus/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
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