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As a major adverse environmental factor in most parts of the world, drought causes substantial crop yield losses. Rice (Oryza sativa) is one of the staple foods for more than one-half of the world’s population. Rice plants are sensitive to even mild drought stress and need almost twice the amount of water compared to wheat (Triticum aestivum) or maize (Zea mays). Arabidopsis (Arabidopsis thaliana) small GTPase Nucleolar GTP-binding protein 1 (AtNOG1) plays a role in biotic stress tolerance. Here, we created transgenic rice lines constitutively overexpressing AtNOG1-1 or AtNOG1-2. We also developed rice RNA interference (RNAi) lines that show downregulation of OsNOG1. AtNOG1-1 and AtNOG1-2 overexpressors showed enhanced drought tolerance without compromising grain yield, whereas OsNOG1-RNAi was more susceptible to drought when compared to wild-type plants. Analysis of physiological parameters showed increased cell sap osmolality, relative water content, and abscisic acid (ABA) level, but decreased leaf water loss in AtNOG1-1 or AtNOG1-2 overexpressor lines compared to the control. We found upregulation of several genes involved in ABA and jasmonic acid (JA) signaling, stomata regulation, osmotic potential maintenance, stress protection, and disease resistance in AtNOG1-1 and AtNOG1-2 overexpressor lines compared to the control. We elucidated the role of NOG1-2 and NOG1-1 in regulation of silica body formation around stomata to prevent transpirational water loss. These results provide an avenue to confer drought tolerance in rice.

Non-alcoholic fatty liver disease (NAFLD) has recently been renamed as metabolic dysfunction-associated fatty liver disease (MAFLD) by the Asian Pacific Association for the Study of the Liver (APASL) to reflect metabolic dysfunction. Vitamin D regulates free fatty acid flux from the periphery to the liver. The association MAFLD and vitamin D has been controversial. We investigated the association of MAFLD, nutrient intake, and vitamin D status in South Korean adults.We analyzed patient responses from the Korea National Health and Nutrition Examination survey (KNHANES) 2010-2011. The disease group was selected as per the latest guidelines. Steatosis was evaluated by the fatty liver index (FLI). Frequency analysis was performed on general characteristics. We compared differences in nutritional status using complex sample adjusted chi-square tests and generalized linear models. After adjusting for age, complex sample logistic regression analysis was used to examine the relationship between MAFLD and vitamin D.Aspartate aminotransferase (AST), alanine aminotransferase (ALT), LDL, triglyceride, creatinine, glucose, nutrient intake, and serum 25(OH)D concentrations were significantly elevated while HDL was reduced in the disease group than in the control group. The OR for 25(OH)D was 1.015 (95% CI: 1.004-1.026, p0.0001). However, MAFLD presented no significant association with vitamin D concentration (OR 1.010, 95% CI: 0.985-1.037, p=0.431) after adjusting for age.We found no significant relationship between MAFLD and serum vitamin D concentration in South Korean adults.

This study aimed to explore the effects of examinees’ perceptions of interlocutors’ proficiency on their test results in paired oral tests. A group of 22 Korean English as a foreign language (EFL) high school students participated in the study. They were divided into three groups based on high, intermediate, and low English proficiency and were interviewed twice: once before the test and once after. Each examinee was paired with and tested with three interlocutors with high, intermediate, and low English proficiency levels. Raw scores from each rater were analyzed to examine potential interactions among the factors using the bias analysis from the Many-Facet Rasch Model. The results showed that the examinees’ perceptions about the effect of interlocutor proficiency on their test results were not consistent nor reliable enough to influence the test results. This study provides evidence that the paired format can be used as a valid and reliable tool to assess EFL learners’ speaking ability regardless of interlocutor proficiency levels, which can be assumed to influence examinees’ perceptions of the oral test results.

Many plant-encoded E3 ligases are known to be involved in plant defense. Here, we report a novel role of E3 ligase SALT- AND DROUGHT-INDUCED RING FINGER1 (SDIR1) in plant immunity. Even though SDIR1 is reasonably well-characterized, its role in biotic stress response is not known. The silencing of SDIR1 in Nicotiana benthamiana reduced the multiplication of the virulent bacterial pathogen Pseudomonas syringae pv. tabaci. The Arabidopsis sdir1 mutant is resistant to virulent pathogens, whereas SDIR1 overexpression lines are susceptible to both host and nonhost hemibiotrophic bacterial pathogens. However, sdir1 mutant and SDIR1 overexpression lines showed hypersusceptibility and resistance, respectively, against the necrotrophic pathogen Erwinia carotovora. The mutant of SDIR1 target protein, i.e., SDIR-interacting protein 1 (SDIR1P1), also showed resistance to host and nonhost pathogens. In SDIR1 overexpression plants, transcripts of NAC transcription factors were less accumulated and the levels of jasmonic acid (JA) and abscisic acid were increased. In the sdir1 mutant, JA signaling genes JAZ7 and JAZ8 were downregulated. These data suggest that SDIR1 is a susceptibility factor and its activation or overexpression enhances disease caused by P. syringae pv. tomato DC3000 in Arabidopsis. Our results show a novel role of SDIR1 in modulating plant defense gene expression and plant immunity. [Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

SUMMARYGLV/RGF peptide encoding genes can be identified in genomes of all plants that can form roots or root-like structures suggesting they were essential for transition of plants to land.In Medicago truncatula, five of fifteen GOLVEN(GLV)/ROOT MERISTEM GROWTH FACTOR (RGF) peptide coding genes were induced during nodule organogenesis and to a varying extent under nitrogen deficiency and auxin treatment. Expression of MtGLV9 and MtGLV10 at nodule initiation sites was dependent on the transcription factor NODULE INCEPTION.Overexpression of all five nodule-induced GLV genes in M. truncatula hairy roots as well as application of the corresponding synthetic peptides resulted in a 25-50% reduction in nodule number indicating GOLVENs are negative regulators of nodule organogenesis.The peptide GOLVEN10 shifted the position of the first formed lateral root (rhizotaxis) as well as the first formed nodule along the longitudinal primary root axis, a phenomenon we term ‘nodulotaxis’, thereby reducing the absolute length of the zone of lateral organ formation on roots.Application of synthetic GOLVEN10 peptide caused an increase in cell number but not cell length in each root cortical cell layer causing an increase in root length and a consequent spatiotemporal delay in formation of the first lateral organ.Plain Language SummaryNodule positioning is an understudied trait, yet it determines the length of the root that can support nodule formation and consequently the total number of functional nodules formed. We identify for the first time, genetic factors called GOLVEN peptides that alter nodule and lateral root positioning on the primary root along with several other traits including nodule organ initiation and root architecture.

Iron–sulfur (Fe–S) clusters are inorganic cofactors that are present in all kingdoms of life as part of a large number of proteins involved in several cellular processes, including DNA replication and metabolism. In this work, we demonstrate an additional role for two Fe–S cluster genes in biotic stress responses in plants. Eleven Fe–S cluster genes, including the NITROGEN FIXATION S-LIKE1 (NFS1) and its interactor FRATAXIN (FH), when silenced in Nicotiana benthamiana, compromised nonhost resistance to Pseudomonas syringae pv. tomato T1. NbNFS1 expression was induced by pathogens and salicylic acid. Arabidopsis (Arabidopsis thaliana) atnfs and atfh mutants, with reduced AtNFS1 or AtFH gene expression, respectively, showed increased susceptibility to both host and nonhost pathogen infection. Arabidopsis AtNFS1 and AtFH overexpressor lines displayed decreased susceptibility to infection by host pathogen P. syringae pv. tomato DC3000. The AtNFS1 overexpression line exhibited constitutive upregulation of several defense-related genes and enrichment of gene ontology terms related to immunity and salicylic acid responses. Our results demonstrate that NFS1 and its interactor FH are involved not only in nonhost resistance but also in basal resistance, suggesting a new role of the Fe–S cluster pathway in plant immunity.

Background Treatment of human lung squamous cell carcinoma (LUSC) using current targeted therapies is limited because of their diverse somatic mutations without any specific dominant driver mutations. These mutational diversities preventing the use of common targeted therapies or the combination of available therapeutic modalities would require a preclinical animal model of this tumor to acquire improved clinical responses. Patient-derived xenograft (PDX) models have been recognized as a potentially useful preclinical model for personalized precision medicine. However, whether the use of LUSC PDX models would be appropriate enough for clinical application is still controversial. Methods In the process of developing PDX models from Korean patients with LUSC, the authors investigated the factors influencing the successful initial engraftment of tumors in NOD scid gamma mice and the retainability of the pathological and genomic characteristics of the parental patient tumors in PDX tumors. Conclusions The authors have developed 62 LUSC PDX models that retained the pathological and genomic features of parental patient tumors, which could be used in preclinical and co-clinical studies. Trial registration Tumor samples were obtained from 139 patients with LUSC between November 2014 and January 2019. All the patients provided signed informed consents. This study was approved by the institutional review board (IRB) of Samsung Medical Center (2018-03-110)

SUMMARY Brachypodium distachyon is an annual C3 grass used as a monocot model system in functional genomics research. Insertional mutagenesis is a powerful tool for both forward and reverse genetics studies. In this study, we explored the possibility of using the tobacco retrotransposon Tnt1 to create a transposon‐based insertion mutant population in B. distachyon. We developed transgenic B. distachyon plants expressing Tnt1 (R0) and in the subsequent regenerants (R1) we observed that Tnt1 actively transposed during somatic embryogenesis, generating an average of 6.37 insertions per line in a population of 19 independent R1 regenerant plants analyzed. In seed‐derived progeny of R1 plants, Tnt1 segregated in a Mendelian ratio of 3:1 and no new Tnt1 transposition was observed. A total of 126 flanking sequence tags (FSTs) were recovered from the analyzed R0 and R1 lines. Analysis of the FSTs showed a uniform pattern of insertion in all the chromosomes (1–5) without any preference for a particular chromosome region. Considering the average length of a gene transcript to be 3.37 kb, we estimated that 29 613 lines are required to achieve a 90% possibility of tagging a given gene in the B. distachyon genome using the Tnt1‐based mutagenesis approach. Our results show the possibility of using Tnt1 to achieve near‐saturation mutagenesis in B. distachyon, which will aid in functional genomics studies of other C3 grasses., Significance Statement Retrotransposable elements transpose from one position in the DNA to another during embryogenesis, causing mutations at the genomic landing site. Here we show that Tnt1, a retrotransposable element from tobacco, can transpose in a monocot plant, Brachypodium distachyon. Based on the analyses of Tnt1 insertions in B. distachyon, we estimated that 29 613 lines would be needed to achieve a 90% probability of tagging every gene in the B. distachyon genome.

Objectives: Sulforaphane, a major ingredient isolated from Brassica oleracea var. italica (broccoli), is known to exhibit anti-inflammatory, anti-cancer, and anti-diabetic effects. In this study, we employed an in vitro model of phorbol 12-myristate 13-acetate and a23187 (PMACI)-stimulated human mast cells (HMC-1 cells) to investigate the anti-allergic inflammatory effects and mechanisms of sulforaphane and Brassica oleracea var. italica extracts. Methods: Cytokine levels were measured by ELISA and quantitative real-time-PCR methods. Caspase-1 activity was determined by caspase-1 assay. Binding mode of sulforaphane within caspase-1 was determined by molecular docking simulation. Protein expression was determined by Western blotting. Results: Water extract of Brassica oleracea var. italica (WE) significantly reduced thymic stromal lymphopoietin (TSLP) secretion and caspase-1 activity on activated HMC-1 cells. In the molecular docking simulation and in vitro caspase-1 assays, sulforaphane regulated caspase-1 activity by docking with the identical binding site of caspase-1. Sulforaphane significantly inhibited the levels of inflammatory mediators including TSLP, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and IL-8 in a dose-dependent manner. Immunoblotting experiments revealed that sulforaphane and WE reduced translocation of NF-κBp65 into the nucleus and phosphorylation of IκBα in the cytosol. Furthermore, phosphorylation of mitogen-activated protein kinases (MAPK) was down-regulated by treatment with sulforaphane or WE. Conclusion: Our findings suggest that sulforaphane and WE have anti-allergic inflammatory effects by intercepting caspase-1/NF-κB/MAPKs signaling pathways.

A novel series of benzylidenethiazolidine-2,4-dione derivatives was synthesized and investigated for 15-hydroxyprostaglandin dehydrogenase (15-PGDH)-scavenging activity, PGE2 release, and wound-healing activity. Among the tested derivatives, seven compounds (3, 9, 11, 12, 13, 14, and 25) resulted in a 50% inhibition of 15-PGDH at concentrations between 0.07 and 0.2 µM and increased PGE2 levels from 300 to over 600% in A549 cells treated with 5.0 and 10.0 µM of the compounds for 12 h. A scratch wound-healing assay using HaCaT cell line was conducted to verify the effects of 10 µM of these compounds on cell regeneration. The closure rate of the scratch wound healing showed that all compounds (3, 9, 11, 12, 13, 14, and 25) had greater wound regeneration effects than the cell growth factor, TGF-β1, which was used as the positive control. In particular, (Z)-N-benzyl-4-((2,4-dioxothiazolidin-5-ylidene)methyl)benzamide (compound 14) showed that the highest wound closure rate, which was 360%; this is about 3.6-fold higher than that of TGF-β1. Overall, these results show that compound 14 may be considered a promising candidate for the development of novel wound-healing agents.

This study aims to develop and validate the Scale of Self-Regulated Language Learning (S2RLL), intended to measure high school students’ self-regulated language learning skills such as grit, self-efficacy, goal orientations, and language learning strategies. A total of 1281 Korean high school students participated in this study. Various evidence for S2RLL validity was collected from these participants. Results from a field expert panel rating agreement and the Rasch analysis offered evidence for content validity. The Rasch analysis also provided evidence for response validity. Internal structure-related evidence for validity was obtained by applying both exploratory and confirmatory factor analysis and calculating various reliability indices. Lastly, evidence for criterion validity was gained by comparing results from S2RLL with those of other instruments that measure constructs similar to S2RLL. We found that S2RLL items appropriately reflected self-regulated language learning skills. From a psychometric perspective, exploratory and confirmatory factor analyses of shared item variance supported the valid internal structure of S2RLL. Moreover, the Rasch analysis offered evidence for the appropriateness of the 5-point Likert scale used by respondents to respond to S2RLL items. Finally, the sub-scales of S2RLL showed moderate to high correlations with those of other scales related to self-regulation. Thus, S2RLL has the potential to help evaluate applicants’ SRL for second language learning. In addition, we make several suggestions for future research in this area.

Nonhost disease resistance is the most common type of plant defense mechanism against potential pathogens. In the present study, the metabolic enzyme formate dehydrogenase 1 (FDH1) was identified to associate with nonhost disease resistance in Nicotiana benthamiana and Arabidopsis thaliana. In Arabidopsis, AtFDH1 was highly upregulated in response to both host and nonhost bacterial pathogens. The Atfdh1 mutants were compromised in nonhost resistance, basal resistance, and gene-for-gene resistance. The expression patterns of salicylic acid (SA) and jasmonic acid (JA) marker genes after pathogen infections in Atfdh1 mutant indicated that both SA and JA are involved in the FDH1-mediated plant defense response to both host and nonhost bacterial pathogens. Previous studies reported that FDH1 localizes to mitochondria, or both mitochondria and chloroplasts. Our results showed that the AtFDH1 mainly localized to mitochondria, and the expression level of FDH1 was drastically increased upon infection with host or nonhost pathogens. Furthermore, we identified the potential co-localization of mitochondria expressing FDH1 with chloroplasts after the infection with nonhost pathogens in Arabidopsis. This finding suggests the possible role of FDH1 in mitochondria and chloroplasts during defense responses against bacterial pathogens in plants.