Overexpression of PtrABF gene, a bZIP transcription factor isolated from Poncirus trifoliata, enhances dehydration and drought tolerance in tobacco via scavenging ROS and modulating expression of stress-responsive genes

<p>Abstract</p> <p>Background</p> <p>Drought is one of the major abiotic stresses affecting plant growth, development and crop productivity. ABA responsive element binding factor (ABF) plays an important role in stress responses via regulating the expression of stress-responsive genes.</p> <p>Results</p> <p>In this study, a gene coding for ABF (<it>PtrABF</it>) was isolated from <it>Poncirus trifoliata </it>(L.) Raf. <it>PtrABF </it>had a complete open reading frame of 1347 bp, encoding a 448 amino acid peptide, and shared high sequence identities with ABFs from other plants. PtrABF was subcellularly targeted to the nucleus, exhibited transactivation activity in yeast cell and could bind to ABRE, supporting its role as a transcription factor. Expression levels of <it>PtrABF </it>were induced by treatments with dehydration, low temperature and ABA. Ectopic expression of <it>PtrABF </it>under the control of a CaMV 35S promoter in transgenic tobacco plants enhanced tolerance to both dehydration and drought. Under dehydration and drought conditions, the transgenic plants accumulated lower levels of reactive oxygen species compared with wild type, accompanied by higher activities and expression levels of three antioxidant enzymes. In addition, steady-state mRNA levels of nine stress-responsive genes coding for either functional or regulatory proteins were induced to higher levels in the transgenic lines with or without drought stress.</p> <p>Conclusions</p> <p><it>PtrABF </it>is a bZIP transcription factor and functions in positive modulation of drought stress tolerance. It may be an important candidate gene for molecular breeding of drought- tolerant plants.</p

catena-Poly[[[tetra­aqua­iron(II)]-μ-5,5′-diazenediylditetra­zolido] dihydrate]

In the title compound, {[Fe(C2N10)(H2O)4]·2H2O}n, the coordin­ation geometry around the Fe(II) atom, which lies on a center of inversion, is distorted octa­hedral, with bonds to four O atoms and two N atoms. The azotetra­zolate ligand displays a bridging coordination mode, forming an infinite zigzag chain. Inter­molecular O—H⋯O and O—H⋯N hydrogen bonding and offset face-to-face π–π stacking inter­actions [centroid–centroid distance = 3.4738 (13) Å] lead to a three-dimensional network

Free field realization of the exceptional current superalgebra \hat{D(2,1;\a)}_k

The free-field representations of the D(2,1;\a) current superalgebra and the corresponding energy-momentum tensor are constructed. The related screening currents of the first kind are also presented.Comment: Latex file, 10 page

(E)-N′-(2-Hydr­oxy-4-methoxy­benzyl­idene)isonicotinohydrazide monohydrate

The title compound, C14H13N3O3·H2O, was prepared by the reaction of 4-methoxy­salicylaldehyde and isonicotinohydrazide in ethanol. The Schiff base mol­ecule is not planar and has an E configuration with respect to the methyl­idene unit. The dihedral angle between the benzene and pyridine rings is 36.8 (2)°. In the mol­ecule there is an intra­molecular O—H⋯N hydrogen bond involving the hydroxyl substituent and the N atom of the 2-hydr­oxy-4-methoxy­benzyl­idene unit. In the crystal, the mol­ecules are linked through inter­molecular O—H⋯O, O—H⋯N and N—H⋯O hydrogen bonds, forming layers parallel to the bc plane

N′-(5-Bromo-2-hydr­oxy-3-methoxy­benzyl­idene)isonicotinohydrazide

The title compound, C14H12BrN3O3, was prepared by reaction of 5-bromo-3-methoxy­salicylaldehyde and isonicotinohydrazide in methanol. The mol­ecule is not planar and adopts a trans configuration with respect to the C=N bond. There is an intra­molecular O—H⋯N hydrogen bond in the mol­ecule. The dihedral angle between the benzene and pyridine rings is 12.2 (2)°. In the crystal structure, mol­ecules are linked through inter­molecular N—H⋯N hydrogen bonds, forming chains running along the c-axis direction

MA2_2Z4_4 Family Heteorstructures: Promises and Prospects

Recent experimental synthesis of ambient-stable MoSi2N4 monolayer have garnered enormous research interests. The intercalation morphology of MoSi2N4 - composed of a transition metal nitride (Mo-N) inner sub-monolayer sandwiched by two silicon nitride (Si-N) outer sub-monolayers - have motivated the computational discovery of an expansive family of synthetic MA2Z4 monolayers with no bulk (3D) material counterpart (where M = transition metals or alkaline earth metals; A = Si, Ge; and N = N, P, As). MA2Z4 monolayers exhibit interesting electronic, magnetic, optical, spintronic, valleytronic and topological properties, making them a compelling material platform for next-generation device technologies. Furthermore, heterostructure engineering enormously expands the opportunities of MA2Z4. In this review, we summarize the recent rapid progress in the computational design of MA2Z4-based heterostructures based on first-principle density functional theory (DFT) simulations - a central \emph{work horse} widely used to understand the physics, chemistry and general design rules for specific targeted functions. We systematically classify the MA2Z4-based heterostructures based on their contact types, and review their physical properties, with a focus on their performances in electronics, optoelectronics and energy conversion applications. We review the performance and promises of MA2Z4-based heterostructures for device applications that include electrical contacts, transistors, spintronic devices, photodetectors, solar cells, and photocatalytic water splitting. This review unveils the vast device application potential of MA2Z4-based heterostructures, and paves a roadmap for the future experimental and theoretical development of MA2Z4-based functional heterostructures and devices.Comment: 32 pages, 15 figure

Poly A- Transcripts Expressed in HeLa Cells

BACKGROUND: Transcripts expressed in eukaryotes are classified as poly A+ transcripts or poly A- transcripts based on the presence or absence of the 3' poly A tail. Most transcripts identified so far are poly A+ transcripts, whereas the poly A- transcripts remain largely unknown. METHODOLOGY/PRINCIPAL FINDINGS: We developed the TRD (Total RNA Detection) system for transcript identification. The system detects the transcripts through the following steps: 1) depleting the abundant ribosomal and small-size transcripts; 2) synthesizing cDNA without regard to the status of the 3' poly A tail; 3) applying the 454 sequencing technology for massive 3' EST collection from the cDNA; and 4) determining the genome origins of the detected transcripts by mapping the sequences to the human genome reference sequences. Using this system, we characterized the cytoplasmic transcripts from HeLa cells. Of the 13,467 distinct 3' ESTs analyzed, 24% are poly A-, 36% are poly A+, and 40% are bimorphic with poly A+ features but without the 3' poly A tail. Most of the poly A- 3' ESTs do not match known transcript sequences; they have a similar distribution pattern in the genome as the poly A+ and bimorphic 3' ESTs, and their mapped intergenic regions are evolutionarily conserved. Experiments confirmed the authenticity of the detected poly A- transcripts. CONCLUSION/SIGNIFICANCE: Our study provides the first large-scale sequence evidence for the presence of poly A- transcripts in eukaryotes. The abundance of the poly A- transcripts highlights the need for comprehensive identification of these transcripts for decoding the transcriptome, annotating the genome and studying biological relevance of the poly A- transcripts

Associations Between Hepatitis B Virus Genotype and Mutants and the Risk of Hepatocellular Carcinoma

Background The risk of hepatocellular carcinoma (HCC) increases with increasing level of hepatitis B virus (HBV) in serum (viral load). However , it is unclear whether genetic characteristics of HBV, including HBV genotype and specific genetic mutations, contribute to the risk of HCC. We examined the HCC risk associated with HBV genotypes and common variants in the precore and basal core promoter (BCP) regions. Methods From January 5, 1991, to December 21, 1992 , baseline blood samples were collected from 2762 Taiwanese men and women who were seropositive for HBV surface antigen but had not been diagnosed with HCC; the samples were tested for HBV viral load by real-time polymerase chain reaction and genotyped by melting curve analysis. Participants who had a baseline serum HBV DNA level greater than 101 copies/ mL (n = 1526) were tested for the precore G 1896A and BCP A 1762T/G1764A mutants by direct sequencing. Incident cases of HCC were ascertained through follow-up examinations and computerized linkage to the National Cancer Registry and death certification profiles. A Cox proportional hazards model was used to estimate the risk of HCC associated with HBV genotype and precore and BCP mutants after adjustment for other risk factors. All statistical tests were two-sided . Results A total of 153 HCC cases occurred during 33847 person-years of follow-up. The HCC incidence rates per 100000 person-years for participants infected with HBV genotype B or C were 305.6 (95% confidence interval [CI] = 236.9 to 388.1) and 785.8 (95% CI = 626.8 to 972.9), respectively. Among participants with a baseline HBV DNA level of at least 10(4) copies/mL, HCC incidence per 100000 person-years was higher for those with the precore G1896 ( wild-type) variant than for those with the G1896A variant ( 955.5 [95% CI = 749.0 to 1201.4] vs 269.4 [95% CI = 172.6 to 400.9]) and for those with the BCP A1762T/G1764A double mutant than for those with BCP A1762/G1764 (wild-type) variant (1149.2 [95% CI = 872.6 to 1485.6] vs 358.7 [95% Cl = 255.1 to 490.4]). The multivariable-adjusted hazard ratio of developing HCC was 1.76 (95% CI = 1.19 to 2.61) for genotype C vs genotype B, 0.34 (95% CI = 0.21 to 0.57) for precore G1896A vs wild type, and 1.73 (95% CI = 1.13 to 2.67 ) for BCP A1762T/G1764A vs wild type. Risk was highest among participants infected with genotype C HBV and wild type for the precore 1896 variant and mutant for the BCP 1762/1764 variant ( adjusted hazard ratio = 2.99, 95% CI = 1.57 to 5.70 , P<.001). Conclusions HBV genotype C and specific alleles of BCP and precore were associated with risk of HCC. These associations were independent of serum HBV DNA level

Eco-friendly synthesis of self-supported N-doped Sb2S3-carbon fibers with high atom utilization and zero discharge for commercial full lithium-ion batteries

Antimony trisulfide (Sb2S3) is a prospective electrode material for lithium-ion batteries (LIBs) because of its thermal stability, low price, and high specific capacity. However, the commercialization of Sb2S3 as an anode material is greatly hindered by its poor electronic conductivity and massive volume variation during charge/discharge cycles. Moreover, growing demand in reducing greenhouse gas emission requires the material preparation process to be pollution free and highly energy efficient. Herein, we introduce, for the first time, an eco-friendly and highly efficient one-step annealing method to construct a three-dimensional (3D) flexible conductive network and buffer matrix for N-doped Sb2S3-carbon fibers (NSSCs) as a high-performance anode. It is assembled by mixing sulfur and antimony in the atomicity level with a stoichiometric ratio as the electrospinning precursor and then annealed in a sealed quartz tube to assure the high atom utilization of nitrogen and sulfur. Benefiting from the 3D structure and compositional advantages, the NSSC electrode with improved conductivity and carbon buffer matrix exhibits superior Li-storage performance. As a result, this work not only promotes the commercialization of antimony trisulfide but also points out a general eco-friendly method, which can be widely applied to synthesize a variety of flexible metal sulfides and metal nitrides with high atom utilization and zero discharge

21-Gene Recurrence Score Assay and Outcomes of Adjuvant Radiotherapy in Elderly Women With Early-Stage Breast Cancer After Breast-Conserving Surgery

Introduction: To assess the role of the 21-gene recurrence score (RS) assay on decision-making of postoperative radiotherapy (RT) following breast-conserving surgery (BCS) in elderly women with early-stage breast cancer.Methods: The 21-gene RS for elderly (≥65 years) women with stage T1–2N0M0 estrogen receptor-positive breast cancer who underwent BCS from 2004 to 2015 was obtained from the Surveillance, Epidemiology, and End Results program. We estimated the association of 21-gene RS and adjuvant RT related to breast cancer-specific survival (BCSS) using propensity score matching (PSM).Results: We identified 18,456 patients, of which 15,326 (83.0%) received postoperative RT. Of identified patients, 58.9, 34.0, and 7.1% of patients had a low-, intermediate-, and high-risk RS, respectively. Receipt of postoperative RT was not related to the year of diagnosis according to the 21-gene RS groups. Multivariate analysis suggested that receipt of postoperative RT was an independent predictor of better BCSS before (hazard ratio [HR] 0.587, 95% confidence interval [CI] 0.426–0.809, P = 0.001) and after (HR 0.613, 95%CI 0.390–0.963, P = 0.034) PSM. However, subgroups analyses indicated that receipt of postoperative RT was related to better BCSS in women with intermediate-risk RS before (HR 0.467, 95%CI 0.283–0.772, P = 0.003) and after (HR 0.389, 95%CI 0.179–0.846, P = 0.017) PSM, but not in women with low- and high-risk RS groups before and after PSM.Conclusions: Although causation cannot be implied, adjuvant RT in elderly women was associated with a greater effect size in patients with an intermediate-risk RS