RESUMEN
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.
RESUMEN
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 â¼600 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 â¼4.2 km3 per millennium, and the current estimate of the total volume of potentially eruptible magma available today is a minimum of â¼315 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.
RESUMEN
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 (97.1â%) and lower sequence similarity (< 97.0â%) to other known species. The genomic DNA G+C content of LNNU 24178T was 68.8â%. 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 80.0â%, 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 23.5â%, respectively. The respiratory quinone detected in LNNU 24178T was ubiquinone-8 (Q-8). The major fatty acids (> 5.0â%) of LNNU 24178T were identified as iso-C15â:â0 (33.9â%), iso-C17â:â0 (8.7â%), iso-C11â:â0 (6.2â%), iso-C16â:â0 (5.7â%), C16â:â0 (5.3â%) and summed feature 9 (iso-C17â:â1ω9c/10-methyl C16â:â0) (21.1â%). 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.
Asunto(s)
Ácidos Grasos , Rizosfera , Ácidos Grasos/química , Filogenia , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , Composición de Base , Técnicas de Tipificación Bacteriana , Análisis de Secuencia de ADN , FosfolípidosRESUMEN
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.
Asunto(s)
Carbonato de Calcio , Minerales , Carbonato de Calcio/química , Calibración , Magnesio , Isótopos de Oxígeno/químicaRESUMEN
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 0-11â% 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 95.5â% 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 19.9â%, respectively. The highest average nucleotide identity value between strain LNNU 22110T and its closest related strain (R. alba KCTC 19413T) was 80.2â%, much lower than the species delineation threshold of 95-96â%. 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 (>10â%) was anteiso-C15â:â0. 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).
Asunto(s)
Chenopodiaceae , Rizosfera , Actinobacteria , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Fosfolípidos , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Microbiología del SueloRESUMEN
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 0-10â% 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 95.4â% 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 18.3â%, 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 72.3â%, respectively. The genome sequence of strain LNNU 331112T showed 69.0-72.3â% 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 (44.6â%) and MK-7 (55.4â%), which differentiated strain LNNU 331112T from other three recognized Hoyosella species. Major fatty acids (>10â%) were C17â:â1 ω8c (33.8â%), C16â:â0 (23.3â%), C17â:â0 (12.8â%) and summed feature 3 (12.9â%), 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).
Asunto(s)
Chenopodiaceae , Mycobacteriaceae/clasificación , Filogenia , Rizosfera , Microbiología del Suelo , Técnicas de Tipificación Bacteriana , Composición de Base , Chenopodiaceae/microbiología , China , ADN Bacteriano/genética , Ácidos Grasos/química , Mycobacteriaceae/aislamiento & purificación , Hibridación de Ácido Nucleico , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
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.
Asunto(s)
Chenopodiaceae , Regulación de la Expresión Génica de las Plantas , Chenopodiaceae/genética , Chenopodiaceae/metabolismo , Respuesta al Choque por Frío , Sequías , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Estrés Fisiológico , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
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 0-6â% 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 (97.1â%) and Amycolatopsis sacchari DSM 44468T (97.0â%). Sequence similarities with type strains of other species of the genus Amycolatopsis were less than 97.0â%. The average nucleotide identity and DNA-DNA hybridization values between strain EGI 650086T and the reference strains were 78.1-79.8â% and 22.1-23.0â%, 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-C16â:â0 and summed feature 4 (iso-C17â:â1 I and/or anteiso-C17â:â1 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).
Asunto(s)
Actinobacteria/clasificación , Chenopodiaceae/microbiología , Filogenia , Raíces de Plantas/microbiología , Actinobacteria/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Glucolípidos/química , Hibridación de Ácido Nucleico , Peptidoglicano/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
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 0-10â% (w/v) NaCl (optimum 0-3â%). The major cellular fatty acids (>10â%) 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 (96.2â%) that was lower than the suggested threshold (97.0â%) 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).
Asunto(s)
Bacillus/clasificación , Capparis/microbiología , Filogenia , Raíces de Plantas/microbiología , Bacillus/genética , Bacillus/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Glucolípidos/química , Hibridación de Ácido Nucleico , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
A novel endophytic actinobacterial strain, designated EGI 6500195T, was isolated from fruits of Capparis spinosa. Growth occurred at 10-45 °C (optimum 30 °C), at pH 6-8 (optimum pH 7) and in the presence of 0-1â% (w/v) NaCl. Strain EGI 6500195T shared highest 16S rRNA gene sequence similarity (97.74â%) with Streptomyces vitaminophilus DSM 41686T and less than 97â% sequence similarity with other members of the genus Streptomyces. The diagnostic amino acid in the peptidoglycan was ll-diaminopimelic acid. Whole-cell hydrolysates contained glucose, ribose, fructose and mannose. The predominant menaquinones were MK-9(H6) and MK-9(H8). The polar lipid profile of strain EGI 6500195T included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylinositol, phosphatidylcholine, three unknown phospholipids, an unknown aminophospholipid and an unknown aminolipid. The cellular fatty acids were anteiso-C15â:â0, anteiso-C17â:â0, iso-C15â:â0, iso-C16â:â0, anteiso-C17â:â1ω9c, summed feature 4 (iso-C17â:â1 I and/or anteiso-C17â:â1 B) and iso-C17â:â1ω9c. The DNA G+C content of strain EGI 6500195T was 74.1 mol%. The level of DNA-DNA relatedness between strain EGI 6500195T and Streptomyces. vitaminophilus DSM 41686T was 14.1±3.5â%. On the basis of the phenotypic, phylogenetic, chemotaxonomic and DNA-DNA hybridization data, strain EGI 6500195T represents a novel species of the genus Streptomyces, for which the name Streptomyces capparidis sp. nov. is proposed. The type strain is EGI 6500195T (=DSM 42145T=JCM 30089T).
Asunto(s)
Capparis/microbiología , Frutas/microbiología , Filogenia , Streptomyces/clasificación , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Peptidoglicano/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Streptomyces/genética , Streptomyces/aislamiento & purificación , Vitamina K 2/análogos & derivadosRESUMEN
An orange-coloured, aerobic, motile, short-rod-shaped bacterial strain, designated EGI 6500337T, was isolated from the surface-sterilized root of a halophyte, Anabasis elatior (C. A. Mey.) Schischk, collected from Urumqi, Xinjiang province, north-west China. Growth occurred at 5-35 °C (optimum 30 °C), at pH 6.0-9.0 (optimum pH 7.0) and in the presence of 0-6 % (w/v) NaCl (optimum 0-1 %). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain EGI 6500337T formed a distinct lineage in the cluster that comprised the genera Aurantimonas and Aureimonas in the family Aurantimonadaceae. The 16S rRNA gene sequence of strain EGI 6500337T shared highest similarity with those of Aurantimonas coralicida DSM 14790T (97.15 %) and Aurantimonas manganoxydans DSM 21871T (97.15 %). Strain EGI 6500337T contained Q-10 as the dominant isoprenoid quinone. The major cellular fatty acids were C18 : 1ω7c and C19 : 0ω8c cyclo. The polar lipid profile of strain EGI 6500337T contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine and phosphatidylethanolamine as major components, similarly to members of the genus Aurantimonas. The DNA G+C content of strain EGI 6500337T was 66.8 mol%. The level of DNA-DNA relatedness between strain EGI 6500337T and Aurantimonas coralicida DSM 14790T was 24.7±2.9 %. On the basis of the phylogenetic analysis, chemotaxonomic data and phenotypic characteristics, strain EGI 6500337T represents a novel species of the genus Aurantimonas, for which the name Aurantimonas endophytica sp. nov. is proposed. The type strain is EGI 6500337T (=KCTC 52296T=CPCC 100904T).
Asunto(s)
Alphaproteobacteria/clasificación , Amaranthaceae/microbiología , Filogenia , Raíces de Plantas/microbiología , Alphaproteobacteria/genética , Alphaproteobacteria/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Fosfolípidos/química , Pigmentación , ARN Ribosómico 16S/genética , Plantas Tolerantes a la Sal/microbiología , Análisis de Secuencia de ADN , Ubiquinona/químicaRESUMEN
KEY MESSAGE: Sl NAC1 functions as a stress-responsive NAC protein involved in the abscisic acid-dependent signaling pathway and enhances transgenic Arabidopsis drought, salt, and cold stress tolerance. NAC (NAM, ATAF1, 2, CUC2) transcription factors constitute the largest families of plant-specific transcription factors, known to be involved in various growth or developmental processes and in regulation of response to environmental stresses. However, only little information regarding stress-related NAC genes is available in Suaeda liaotungensis K. In this study, we cloned a full-length NAC gene (1,011 bp) named SlNAC1 using polymerase chain reaction from Suaeda liaotungensis K. and investigated its function by overexpression in transgenic Arabidopsis. SlNAC1 contains an NAC-conserved domain. Its expression in S. liaotungensis was induced by drought, high-salt, and cold (4 °C) stresses and by abscisic acid. Subcellular localization experiments in onion epidermal cells indicated that SlNAC1 is localized in the nucleus. Yeast one-hybrid assays showed that SlNAC1 functions as a transcriptional activator. SlNAC1 transgenic Arabidopsis displayed a higher survival ratio and lower rate of water loss under drought stress; a higher germination ratio, higher survival ratio, and lower root inhibition rate under salt stress; a higher survival ratio under cold stress; and a lower germination ratio and root inhibition rate under abscisic acid treatment, compared with wild-type Arabidopsis. These results suggested that SlNAC1 functions as a stress-responsive NAC protein involved in the abscisic acid-dependent signaling pathway and may have potential applications in transgenic breeding to enhance crops' abiotic stress tolerances.
Asunto(s)
Arabidopsis/fisiología , Chenopodiaceae/genética , Regulación de la Expresión Génica de las Plantas , Estrés Fisiológico , Factores de Transcripción/genética , Ácido Abscísico/farmacología , Secuencia de Aminoácidos , Arabidopsis/genética , Núcleo Celular/metabolismo , Frío , Sequías , Expresión Génica , Datos de Secuencia Molecular , Filogenia , Reguladores del Crecimiento de las Plantas/farmacología , Hojas de la Planta/genética , Hojas de la Planta/fisiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Estructura Terciaria de Proteína , Sales (Química) , Plantones/genética , Plantones/fisiología , Alineación de Secuencia , Factores de Transcripción/metabolismoRESUMEN
Deep carbon cycle is crucial for mantle dynamics and maintaining Earth's habitability. Recycled carbonates are a strong oxidant in mantle carbon-iron redox reactions, leading to the formation of highly oxidized mantle domains and deep carbon storage. Here we report high Fe3+/∑Fe values in Cenozoic intraplate basalts from eastern China, which are correlated with geochemical and isotopic compositions that point to a common role of carbonated melt with recycled carbonate signatures. We propose that the source of these highly oxidized basalts has been oxidized by carbonated melts derived from the stagnant subducted slab in the mantle transition zone. Diamonds formed during the carbon-iron redox reaction were separated from the melt due to density differences. This would leave a large amount of carbon (about four times of preindustrial atmospheric carbon budget) stored in the deep mantle and isolated from global carbon cycle. As such, the amounts of subducted slabs stagnated at mantle transition zone can be an important factor regulating the climate.
RESUMEN
To improve the stress tolerance of crops, many genes, including transcription factors, have been expressed in transgenic plants using either constitutive or stress-inducible promoters. However, transgenic plants that show strong constitutive expression of transcription factors often suffer from many undesirable phenotypes, such as stunted growth and reduced yield. In the present study, the betaine aldehyde dehydrogenase (BADH) gene, cloned from Suaeda liaotungensis and, controlled by the Cauliflower mosaic virus (CaMV) 35S promoter or stress-inducible promoter of BADH (P5: -300 to +62 bp), was transformed into tomato (Solanum lycopersicum). The transformants with single copy of SlBADH were determined by real time PCR. Expression of SlBADH in the P5:BADH transgenic plants exhibited salt induced and was higher than that in CaMV35S:BADH under salt stress. The SlBADH enhanced salt tolerance of P5:BADH and CaMV35S:BADH transformants. And SlBADH in P5:BADH plants did not affect the growth of transformants. Consequently, we conclude that the P5 promoter can drive increased expression of SlBADH in transgenic tomato under salt stress and increase salt tolerance without affecting plant growth.
Asunto(s)
Proteínas de Plantas/genética , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/fisiología , Tolerancia a la Sal/genética , Solanum lycopersicum/genética , Solanum lycopersicum/fisiología , Caulimovirus , Chenopodiaceae/genética , Regulación de la Expresión Génica de las Plantas , Regiones Promotoras Genéticas , Cloruro de Sodio/metabolismo , Cloruro de Sodio/farmacologíaRESUMEN
BACKGROUND: Endocardial fibroelastosis (EFE) is a diffuse endocardial collagen and elastin hyperplasia disease of unknown etiology, which may be accompanied by myocardial degenerative changes leading to acute or chronic heart failure. However, acute heart failure (AHF) without obvious associated triggers is rare. Prior to the report of endomyocardial biopsy, the diagnosis and treatment of EFE are highly susceptible to being confounded with other primary cardiomyopathies. Here, we report a case of pediatric AHF caused by EFE mimicking dilated cardiomyopathy (DCM), with the aim of providing a valuable reference for clinicians to early identify and diagnose EFE-induced AHF. CASE SUMMARY: A 13-mo-old female child was admitted to hospital with retching. Chest X-ray demonstrated enhanced texture in both lungs and an enlarged heart shadow. Color doppler echocardiography showed an enlarged left heart with ventricular wall hypokinesis and decreased left heart function. Abdominal color ultrasonography revealed a markedly enlarged liver. Pending the result of the endomyocardial biopsy report, the child was treated with a variety of resuscitative measures including nasal cannula for oxygen, intramuscular sedation with chlorpromazine and promethazine, cedilanid for cardiac contractility enhancement, and diuretic treatment with furosemide. Subsequently, the child's endomyocardial biopsy report result was confirmed as EFE. After the above early interventions, the child's condition gradually stabilized and improved. One week later, the child was discharged. During a 9-mo follow-up period, the child took intermittent low-dose oral digoxin with no signs of recurrence or exacerbation of the heart failure. CONCLUSION: Our report suggests that EFE-induced pediatric AHF may present in children over 1 year of age without any apparent precipitants, and that the associated clinical presentations are grossly similar to that of pediatric DCM. Nonetheless, it is still possible to be diagnosed effectively on the basis of the comprehensive analysis of auxiliary inspection findings before the result of the endomyocardial biopsy is reported.
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The transmission electron microscopy (TEM) specimen with thickness in nanometer scale is susceptible to hydrocarbon contamination and oxidation, and the specimen holder is also susceptible to contaminants, which would deteriorate the quality of TEM imaging and degrade the efficiency of TEM experiments. Conventional pretreatment devices often have limited functions and low practicability, which may cause problems for TEM specimens and holders. In this work, a multifunctional apparatus for plasma cleaning and storage of TEM specimens and specimen holders is developed based on the specific design of the vacuum joints. The apparatus includes a plasma cleaning system, holder storage station, and specimen storage station, which share the same vacuum system. The cleaning of hydrocarbon contaminants on the specimen and storage of the specimens and holders can be achieved simultaneously in this apparatus. TEM imaging and energy-dispersive X-ray spectroscopy (EDS) analyses of two treated specimens using the apparatus demonstrated that it could effectively remove hydrocarbon contaminants on the specimen. The holder storage station, used to preserve TEM holders in vacuum conditions, can also be modified as a specimen storage station by an appropriate design of the specimen storage platform, in which specimens are protected from water and contaminations. The designed apparatus not only robustly avoids damage to the ultrathin specimen and holders but also improves the working efficiency and reduces costs. These advantages could make our apparatus more appealing for the complement to the present commercial plasma cleaning and storage devices. HIGHLIGHTS: An apparatus for the pretreatment of transmission electron microscopy (TEM) specimens and specimen holders with three functions-plasma cleaning, holder storage, and specimen storage-was designed and fabricated. Using this single apparatus, the cleaning of hydrocarbon contaminants on the specimen and storage of the specimens and holders can be achieved simultaneously. The designed apparatus can not only robustly avoid damage to the ultrathin specimen and holders but also improve the working efficiency and reduce costs by adopting a single vacuum system. These advantages could make our apparatus more appealing for the complement to the present commercial plasma cleaning and storage devices.
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Identifying the oldest evidence for the recycling of hydrated crust into magma on Earth is important because it is most effectively achieved by subduction. However, given the sparse geological record of early Earth, the timing of first supracrustal recycling is controversial. Silicon and oxygen isotopes have been used as indicators of crustal evolution on Archean igneous rocks and minerals to trace supracrustal recycling but with variable results. We present Si-O isotopes of Earth's oldest rocks [4.0 billion years ago (Ga)] from the Acasta Gneiss Complex, northwest Canada, obtained using multiple techniques applied to zircon, quartz, and whole rock samples. Undisturbed zircon is considered the most reliable recorder of primary Si signatures. By combining reliable Si isotope data from the Acasta samples with filtered data from Archean rocks globally, we observe that widespread evidence for a heavy Si signature is recorded since 3.8 Ga, marking the earliest record of surface silicon recycling.
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Planeta Tierra , Silicio , Isótopos de Oxígeno , CanadáRESUMEN
Isotope dilution thermal ionization mass spectrometry (ID-TIMS) is the standard technique used to achieve precise (143)Nd/(144)Nd and (147)Sm/(144)Nd isotope ratios and accurate elemental concentrations of Sm-Nd. However, in previous studies, purified Sm and Nd fractions must be individually loaded onto different filaments for their accurate determination using TIMS because of severe isobaric interferences. Thus, the classical ID-TIMS technique is time consuming and laborious. In this study, a new method is proposed, which is able to acquire both ratios of (143)Nd/(144)Nd and (147)Sm/(144)Nd and concentrations of Sm-Nd simultaneously on the same filament arrangement. The measurement time and filament consumption are reduced by 50% with the current method, and therefore, the operation cost of TIMS is significantly reduced. A mixed (152)Sm-(148)Nd spike was employed to achieve accurate results after spike subtraction and isobaric interference corrections. Results obtained from a series of standard rock samples are in good agreement with recommended values, within ±0.003% for the (143)Nd/(144)Nd ratio and ±1% for the (147)Sm/(144)Nd ratio.
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BACKGROUND: This study was designed to determine the pattern and correlation between expression of the HIF-1α transcriptional targets TGM2 and BNIP3 in laryngeal cancer, and investigate the association of BNIP3 and TGM2 with clinical outcome in laryngeal squamous cell carcinoma (SCC) patients receiving postoperative radiotherapy. METHODS: Immunostaining with antibodies specific to BNIP3 and TGM2 was performed in formalin-fixed, paraffin-embedded specimens from 148 laryngeal SCC patients. BNIP3 and TGM2 expression was scored as high or low, based on the number of tumor cells stained and the staining intensity. All patients received postoperative radiotherapy. Patient follow up and clinicopathological data were compared using the Chi-squared test, univariate and multivariate analyses, and survival curves were generated using the Kaplan-Meier method and log-rank test. RESULTS: The 3, 5 and 10-year overall survival rates (OS) for all patients were 77.7%, 71.6%, 56.4%, respectively. Primary tumor site, T stage, overall stage, lymph-node metastasis, BNIP3 expression and TGM2 expression were significant prognostic factors for OS in univariate analysis. Negative cervical lymph nodes, high BNIP3 expression and low TGM2 expression were independent prognostic factors of improved OS in multivariate analysis. BNIP3 expression correlates with TGM2 expression in laryngeal SCC (P = 0.012). CONCLUSIONS: This study indicates that lymph-node metastasis, BNIP3 expression and TGM2 expression are independent prognostic factors in laryngeal SCC patients receiving postoperative radiotherapy. Further studies are required to investigate how BNIP3 and/or TGM2 influence the prognosis of laryngeal SCC patients treated with postoperative radiotherapy, and to determine how TGM2 and BNIP3 expression are regulated.
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Carcinoma de Células Escamosas/diagnóstico , Proteínas de Unión al GTP/metabolismo , Neoplasias Laríngeas/diagnóstico , Proteínas de la Membrana/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Transglutaminasas/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/fisiología , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirugía , Terapia Combinada , Femenino , Proteínas de Unión al GTP/fisiología , Humanos , Neoplasias Laríngeas/metabolismo , Neoplasias Laríngeas/radioterapia , Neoplasias Laríngeas/cirugía , Masculino , Proteínas de la Membrana/fisiología , Persona de Mediana Edad , Cuidados Posoperatorios , Valor Predictivo de las Pruebas , Pronóstico , Proteína Glutamina Gamma Glutamiltransferasa 2 , Proteínas Proto-Oncogénicas/fisiología , Radioterapia Adyuvante , Estudios Retrospectivos , Transglutaminasas/fisiología , Resultado del Tratamiento , Adulto JovenRESUMEN
Background: The internalizing behavior problems (IBPs) of left-behind children (LBC) due to parental migration are a widespread public health concern in China. A previous study showed that the detection rate of behavioral problems in the Hui was far higher than in the LBC of the Han nationality. However, to date, limited research has focused on IBPs in Chinese LBC of the Hui nationality. The aims of this present study are to explore the prevalence of IBPs and the influencing factors among the Hui LBC in the rural areas of China. Methods: A cross-sectional study was conducted among school students from the southern rural areas in Ningxia, China (2012-2013). The caregivers or parents assessed IBPs using Achenbach's Child Behavior Checklist for parents. The children completed the Egma Minnen av Bardndosnauppforstran, Junior Eysenck Personality Questionnaire and Piers-Harris Children's Self-concept Scale. Data on 383 Hui LBC aged 6-16 y were included in this study. Multivariate logistic regression analysis was used to examine the relationships between the independent variables and children's internalizing behaviors. Results: Among the Hui population, the prevalence of IBPs in LBC and non-left-behind children (non-LBC) was 21.67% (83 of 383) and 18.18% (104 of 572), respectively, with no significant difference between these two groups (χ 2 = 1.77 and P = 0.18). However, among males of the Hui population, the prevalence of IBPs in LBC was 22.16%, which is significantly higher than in non-LBC (14.07%; χ 2 = 5.07; and P = 0.02). By controlling for gender and age, the multivariate logistic regression analysis showed that a mother highly favoring the subject (odds ratio [OR] = 2.70), average levels of neuroticism (OR = 9.01), and high levels of neuroticism (OR = 8.44) were risk factors for IBPs in Hui LBC. Conclusion: Our findings suggest that IBPs among male LBC of the Hui nationality in rural China were positively related to parental migration. Positive measures should be taken to prevent IBPs of male LBC of the Hui nationality in rural China in terms of personality development and parental childrearing patterns.