Transcriptional repressor RST1 controls salt tolerance and grain yield in rice by regulating gene expression of asparagine synthetase.

Salt stress impairs nutrient metabolism in plant cells, leading to growth and yield penalties. However, the mechanism by which plants alter their nutrient metabolism processes in response to salt stress remains elusive. In this study, we identified and characterized the rice (Oryza sativa) rice salt tolerant 1 (rst1) mutant, which displayed improved salt tolerance and grain yield. Map-based cloning revealed that the gene RST1 encoded an auxin response factor (OsARF18). Molecular analyses showed that RST1 directly repressed the expression of the gene encoding asparagine synthetase 1 (OsAS1). Loss of RST1 function increased the expression of OsAS1 and improved nitrogen (N) utilization by promoting asparagine production and avoiding excess ammonium (NH4+) accumulation. RST1 was undergoing directional selection during domestication. The superior haplotype RST1Hap III decreased its transcriptional repression activity and contributed to salt tolerance and grain weight. Together, our findings unravel a synergistic regulator of growth and salt tolerance associated with N metabolism and provide a new strategy for the development of tolerant cultivars.

The transcription factor OsMYBc and an E3 ligase regulate expression of a K+ transporter during salt stress.

Sodium (Na+) and potassium (K+) homeostasis is essential for plant survival in saline soils. A member of the High-Affinity K+ Transporter (HKT) family in rice (Oryza sativa), OsHKT1;1, is a vital regulator of Na+ exclusion from shoots and is bound by a MYB transcription factor (OsMYBc). Here, we generated transgenic rice lines in the oshkt1;1 mutant background for genetic complementation using genomic OsHKT1;1 containing a native (Com) or mutated (mCom) promoter that cannot be bound by OsMYBc. In contrast to wild-type (WT) or Com lines, the mCom lines were not able to recover the salt-sensitive phenotype of oshkt1;1. The OsMYBc-overexpressing plants were more tolerant to salt stress than WT plants. A yeast two-hybrid screen using the OsMYBc N-terminus as bait identified a rice MYBc stress-related RING finger protein (OsMSRFP). OsMSRFP is an active E3 ligase that ubiquitinated OsMYBc in vitro and mediated 26S proteasome-mediated degradation of OsMYBc under semi-in vitro and in vivo conditions. OsMSRFP attenuated OsMYBc-mediated OsHKT1;1 expression, and knockout of OsMSRFP led to rice salt tolerance. These findings uncover a regulatory mechanism of salt response that fine-tunes OsHKT1;1 transcription by ubiquitination of OsMYBc.

OsCYBDOMG1, a cytochrome b561 domain-containing protein, regulates salt tolerance and grain yield in rice.

KEY MESSAGE: OsCYBDOMG1 positively regulates salt tolerance, plant growth, and grain yield by affecting ascorbate biosynthesis and redox state. Soil salinity is a major abiotic stress affecting rice growth and productivity. Many genes involved in the salt stress response have been identified, but the precise mechanisms underlying salt tolerance remain unclear. In this study, we isolated a salt-sensitive mutant of rice, rss5, which exhibited more severe wilting and chlorosis with a significant increase in lipid peroxidation, electrolyte leakage, and shoot Na+ concentration compared to wild-type plants. Map-based cloning, MutMap analysis, and genetic complementation revealed that a single-nucleotide mutation in a gene encoding a cytochrome b561 domain-containing protein (OsCYBDOMG1) was responsible for the mutant phenotype of rss5. The OsCYBDOMG1 gene was mainly expressed in young shoots and nodes, and the encoded protein was principally located in the plasma membrane and endoplasmic reticulum. Mutations of OsCYBDOMG1 resulted in decreased ascorbic acid (AsA) content and AsA/DHA (dehydroascorbate) ratio, which led to increased H2O2 accumulation and reduced salt tolerance. Moreover, plant growth and grain yield of rss5 and the OsCYBDOMG1 knockout mutant (cr-1) were significantly decreased compared to wild-type plants under normal conditions. The elite haplotype of OsCYBDOMG1 associated with higher salt tolerance and grain width and weight was mainly existed in japonica varieties. These results suggest that OsCYBDOMG1 plays an important role in the regulation of salt tolerance, plant growth, and grain yield in rice.

A Multifunctional Ionic Liquid Additive Enabling Stable and Efficient Perovskite Light-Emitting Diodes.

The electroluminescence performance and long-term stability of perovskite light-emitting diodes (PeLEDs) are greatly affected by the film quality of perovskite emitting layer. Herein, the authors employ an ionic liquid, 1-butyl-3-methylimidazolium trifluoromethanesulfonate ([BMIm]OTf), to manipulate the growth of quasi-2D perovskite films by providing heterogeneous nucleation sites. The [BMIm]OTf molecules simultaneously realize uniform perovskite films by reducing the contact angles of precursor solution on the hole transport layer (HTL), and eliminate defect states through bonding [BMIm]+ cations to negatively-charged uncoordinated Br and OTf- anions to uncoordinated Pb2+ defects that effectively suppresses the defect states assisted nonradiative recombination in perovskite films. As a result, the efficiency and the operational lifetime of the resultant PeLED are enhanced by more than twofold and threefold, respectively, achieving a maximum external quantum efficiency of 17.6% and an operational lifetime of over 500 min at an initial brightness of 100 cd m-2 .

The rice aldehyde oxidase OsAO3 gene regulates plant growth, grain yield, and drought tolerance by participating in ABA biosynthesis.

Abscisic acid (ABA) regulates many aspects of plant growth and development and the responses to abiotic stresses. Arabidopsis aldehyde oxidase 3 (AAO3) catalyzes the final step of ABA biosynthesis. We cloned and functionally characterized a novel aldehyde oxidase gene, OsAO3, the rice homolog of AAO3. OsAO3 was expressed in germinated seeds, roots, leaves, and floral organs, particularly in vascular tissues and guard cells, and its expression was significantly induced by exogenous ABA and mannitol. Mutation and overexpression of OsAO3 decreased and increased ABA levels, respectively, in seedling shoots and roots under both normal and drought stress conditions. The osao3 mutant exhibited earlier seed germination, increased seedling growth, and decreased drought tolerance compared to the wild-type, OsAO3-overexpressing lines exhibited the opposite phenotype. Mutation and overexpression of OsAO3 increased and decreased grain yield, respectively, by affecting panicle number per plant, spikelet number per panicle, and spikelet fertility. Thus, OsAO3 may participate in ABA biosynthesis, and is essential for regulation of seed germination, seedling growth, grain yield, and drought tolerance in rice.

A bHLH protein, OsBIM1, positively regulates rice leaf angle by promoting brassinosteroid signaling.

Rice leaf angle is an important agronomic trait determining plant architecture and crop yield. Brassinosteroids (BRs) play crucial roles in controlling rice leaf angle, thus an increasing number of researches were focused on the BR signaling pathway in rice. However, the orthologs of some important components in Arabidopsis BR signaling have not yet been characterized in rice. In this study, we identified a rice bHLH transcription factor named OsBIM1, as the closest rice homolog of AtBIM1 (BES1-Interacting MYC-like Protein1). Overexpression of OsBIM1 significantly increases rice leaf angles, whereas the T-DNA knock-out mutant osbim1 and wide type (WT) showed similar leaf inclination. OsBIM1 overexpression enhances the sensitivity and response to BR treatment in rice. Gene expression analysis showed that the overexpression of OsBIM1 significantly increased the transcripts of INCREASED LEAF INCLINATION1 (OsILI1) that functions as a key transcription factor promoting BR signaling and response. Meanwhile, OsBIM1 inhibited the expression of DWARF2 (OsD2, a key enzyme in BR biosynthesis pathway). OsBIM1 can bind with OsILI1 promoter and enhance OsILI1 expression in response to BR treatment. The promoting effect of OsBIM1 overexpression on leaf angle can still be observed at harvest stage, but overexpression of OsBIM1 resulted in smaller grain size and reduced yield. These results indicate that OsBIM1 functions as a positive regulator in BR signaling, and its overexpression increases rice lamina inclination by promoting BR sensitivity and response.

Mendelian randomization analysis reveals causal relationships between circulating cell traits and renal disorders.

Purpose: The aim of this study was to investigate the causal relationships between circulating cell traits and risk of renal disorders. Methods: We applied a comprehensive two-sample Mendelian randomization (MR) analysis. Single nucleotide polymorphisms (SNPs) from publicly available genome-wide association studies (GWAS) databases were utilized. Genetically predicted instrumental variables of human blood cell traits were extracted from Blood Cell Consortium (BCX) while data on renal diseases was obtained from Finngen consortium. The primary MR analysis was conducted using the inverse variance weighted (IVW) method, with the weighted median (WM) and MR-Egger models used as additional methods. Sensitivity analyses, including MR-PRESSO, radial regression and MR-Egger intercept were conducted to detect outliers and assess horizontal pleiotropy. We further utilized the leave-one-out analysis to assess the robustness of the results. Causal associations were considered significant based on false rate correction (FDR), specifically when the IVW method provided a pFDR < 0.05. Results: Our results demonstrated that both white blood cell (WBC) count (OR = 1.50, 95% CI = 1.10-2.06, pFDR = 0.033, pIVW = 0.011) and lymphocyte count (OR = 1.50, 95% CI = 1.13-1.98, pFDR = 0.027, pIVW = 0.005) were causally associated with a higher risk of IgA nephropathy. Furthermore, WBC count was identified as a significant genetic risk factor for renal malignant neoplasms (OR = 1.23, 95% CI = 1.06-1.43, pFDR = 0.041, pIVW = 0.007). Additionally, an increased level of genetically predicted eosinophils was found to be causally associated with a higher risk of diabetic nephropathy (OR = 1.21, 95% CI = 1.08-1.36, pFDR = 0.007, pIVW = 0.001). No evidence of pleiotropy was determined. Conclusion: Our findings provide evidence of causal associations of circulating WBC count, lymphocyte count and IgA nephropathy, WBC count and renal malignant neoplasms, and eosinophil count and diabetic nephropathy. These results have the potential to contribute to the development of novel diagnostic options and therapeutic strategies for renal disorders.

Research on gas emission quantity prediction model based on EDA-IGA.

In order to accurately predict the possible gas emission quantity in coal mines, it is proposed to use the multi-thread calculation of the Immune Genetic Algorithm (IGA) and injection of vaccines to improve the accuracy of prediction and combine the Estimation of Distribution Algorithm (EDA) to the distribution probability of excellent populations. Calculating, and selecting excellent populations for iteration, optimize the population generation process of the Immune Genetic Algorithm, so that the population quality is continuously optimized and improved, and the optimal solution is obtained, thereby establishing a gas emission quantity prediction model based on the Immune Genetic Algorithm and Estimation of Distribution Algorithm. Using the 9136 mining face with gas emission hazards in a coal mine from Shandong Province in China as the prediction object, the absolute gas emission quantity is used to scale the gas emission quantity, and it is found that the model can accurately predict the gas emission quantity, which is consistent with the on-site emission unanimous. In the prediction comparison with IGA, it is found that the accuracy of the prediction results has increased by 9.51%, and the number of iterations to achieve the required goal has been reduced by 67%, indicating that the EDA has a better role in optimizing the population update process such as genetic selection of the IGA. Comparing the prediction results of other models, it is found that the prediction accuracy of the EDA-IGA is 94.93%, which is the highest prediction accuracy, indicating that this prediction model can be used as a new method for the prediction of coal mine gas emission. Accurately predicting the gas emission quantity can provide guidance for safe mining in coal mines. The gas emission quantity can also be used as a safety indicator to reduce the possibility of coal mine accidents, ensure the personal safety of coal miners and reduce economic losses in coal mines.

Poly(l-Ornithine)-Based Polymeric Micelles as pH-Responsive Macromolecular Anticancer Agents.

Anticancer peptides and polymers represent an emerging field of tumor treatment and can physically interact with tumor cells to address the problem of multidrug resistance. In the present study, poly(l-ornithine)-b-poly(l-phenylalanine) (PLO-b-PLF) block copolypeptides were prepared and evaluated as macromolecular anticancer agents. Amphiphilic PLO-b-PLF self-assembles into nanosized polymeric micelles in aqueous solution. Cationic PLO-b-PLF micelles interact steadily with the negatively charged surfaces of cancer cells via electrostatic interactions and kill the cancer cells via membrane lysis. To alleviate the cytotoxicity of PLO-b-PLF, 1,2-dicarboxylic-cyclohexene anhydride (DCA) was anchored to the side chains of PLO via an acid-labile ß-amide bond to fabricate PLO(DCA)-b-PLF. Anionic PLO(DCA)-b-PLF showed negligible hemolysis and cytotoxicity under neutral physiological conditions but recovered cytotoxicity (anticancer activity) upon charge reversal in the weakly acidic microenvironment of the tumor. PLO-based polypeptides might have potential applications in the emerging field of drug-free tumor treatment.

Efficacy and safety of single-dose intravitreal dexamethasone implant in non-infectious uveitic macular edema: A systematic review and meta-analysis.

Purpose: We conducted a systematic review and meta-analysis to investigate the efficacy and safety of single-dose intravitreal dexamethasone (DEX) implant for treating non-infectious uveitic macular edema (UME). Methods: Studies including clinical outcomes of the DEX implant in UME were comprehensively searched in PubMed, Embase, and Cochrane databases for potential studies from inception to July 2022. The primary outcomes were best corrected visual acuity (BCVA) and central macular thickness (CMT) during the follow-up period. Stata 12.0 was used to perform the statistical analyses. Results: Six retrospective studies and one prospective investigation involving 201 eyes were ultimately included. Significantly improved BCVA was observed from baseline to 1 month (WMD = -0.15, 95%CI = -0.24, -0.06), 3 months (WMD = -0.22, 95%CI = -0.29, -0.15), and 6 months (WMD = -0.24, 95%CI = -0.35, -0.13), after single-dose DEX implant. When considering CMT, macular thickness of 1 month (WMD = -179.77, 95%CI = -223.45, -136.09), 3 months (WMD = -179.13, 95%CI = -232.63, -125.63), and 6 months (WMD = -140.25, 95%CI = -227.61, -52.88) decreased in comparison with baseline, with statistical significance. Conclusion: Based on the current results, this meta-analysis confirmed favorable visual prognosis and anatomical improvement in patients with UME, after receiving the single-dose DEX implant. The most common adverse event is increased intraocular pressure, which could be controlled with topical medications.Systematic Review Registration:https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022325969.

Biocontrol Microneedle Patch: A Promising Agent for Protecting Citrus Fruits from Postharvest Infection.

With increasing human awareness of food safety, the replacement of highly toxic pesticides with biocompatible antimicrobials has become a trend. This study proposes a biocontrol microneedle (BMN) to expand the application of the food-grade preservative epsilon-poly-L-lysine (ε-PL) in fruit preservatives by utilizing a dissolving microneedle system. The macromolecular polymer ε-PL not only possesses broad-spectrum antimicrobial activity but also exhibits good mechanical properties. With the addition of a small amount of polyvinyl alcohol, the mechanical strength of the ε-PL-based microneedle patch could be further improved to achieve an enhanced failure force of needles at 1.6 N/needle and induce an approximately 96% insertion rate in citrus fruit pericarps. An ex vivo insertion test revealed that the microneedle tips could be effectively inserted into the citrus fruit pericarp, rapidly dissolve within 3 min, and produce inconspicuous needle holes. Moreover, the high drug loading capacity of BMN was observed to reach approximately 1890 µg/patch, which is essential for enhancing the concentration-dependent antifungal activity of ε-PL. The drug distribution study has confirmed the feasibility of mediating the local diffusion of EPL in the pericarp through BMN. Therefore, BMN has great potential to reduce the incidence of invasive fungal infections in local areas of citrus fruit pericarp.

Retinal and choroidal microvascular alterations in Behcet's disease without ocular manifestations: A systematic review and meta-analysis.

Purpose: We performed a systematic review and meta-analysis to examine the microvascular alterations in non-ocular Behcet's disease (BD) using optical coherence tomography angiography (OCTA). Methods: A comprehensive search was performed in Pubmed, Embase and Cochrane databases for eligible studies from inception to February 2022. Detailed clinical demographics were extracted from each study by two independent reviewers. The weighted mean difference (WMD) and 95% confidence intervals (CI) were used to compare the OCTA parameters between non-ocular BD and healthy controls. Stata 12.0 was adopted to conduct statistical analyses. Results: Ten cross-sectional studies involving 386 eyes in non-ocular BD and 418 eyes in healthy volunteers were ultimately included in the present analysis. When considering superficial capillary plexus (SCP) and deep capillary plexus (DCP), no significant differences of vessel densities in the whole enface image, fovea and perifovea were evaluated between two groups. Significantly reduced parafoveal vessel density of SCP was observed in non-ocular BD in comparison with healthy group (WMD = -1.33, 95%CI: -1.78, -0.89; I 2 = 0.6%), while slightly decreased parafoveal vessel density was assessed in DCP (WMD = -1.47, 95%CI: -3.30, 0.35; I 2 = 89.3%). Significantly increasing foveal avascular zone (FAZ) area was observed in non-ocular BD when compared to healthy controls (WMD = 0.11, 95%CI: 0.03, 0.19; I 2 = 95.3%). There was no significant difference in flow area of choriocapillaris between non-ocular BD and control group (WMD = 0.06, 95%CI: -0.19, 0.32; I 2 = 0%). Conclusion: Based on current analysis, our results demonstrated significantly lower parafoveal vessel density of SCP and lager FAZ area in full vasculature in non-ocular BD. The retinal microvascular alterations appear before the emergence of ocular manifestations. Systematic Trial Registration: [https://www.crd.york.ac.uk/PROSPERO/], identifier [CRD42021244856].

Comparative analysis of chloroplast genomes of three medicinal Carpesium species: Genome structures and phylogenetic relationships.

Carpesium (Asteraceae) is a genus that contains many plant species with important medicinal values. However, the lack of chloroplast genome research of this genus has greatly hindered the study of its molecular evolution and phylogenetic relationship. This study used the Illumina sequencing platform to sequence three medicinal plants of the Carpesium genus: Carpesium abrotanoides, Carpesium cernuum, and Carpesium faberi, obtaining three complete chloroplast genome sequences after assembly and annotation. It was revealed that the three chloroplast genomes were typical quadripartite structures with lengths of 151,389 bp (C. abrotanoides), 151,278 bp (C. cernuum), and 151,250 bp (C. faberi), respectively. A total of 114 different genes were annotated, including 80 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. Abundant SSR loci were detected in all three chloroplast genomes, with most composed of A/T. The expansion and contraction of the IR region indicate that the boundary regions of IR/SC are relatively conserved for the three species. Using C. abrotanoides as a reference, most of the non-coding regions of the chloroplast genomes were significantly different among the three species. Five different mutation hot spots (trnC-GCA-petN, psaI, petA-psbJ, ndhF, ycf1) with high nucleotide variability (Pi) can serve as potential DNA barcodes of Carpesium species. Additionally, phylogenetic evolution analysis of the three species suggests that C. cernuum has a closer genetic relationship to C. faberi than C. abrotanoides. Simultaneously, Carpesium is a monophyletic group closely related to the genus Inula. Complete chloroplast genomes of Carpesium species can help study the evolutionary and phylogenetic relationships and are expected to provide genetic marker assistance to identify Carpesium species.

Preparation and characterization of n-hydroxyapatite/PCL-pluronic-PCL nanocomposites for tissue engineering.

In this paper, a new kind of polymeric nanocomposite materials based on nano-hydroxyapatite (n-HA) and PCL-Pluronic-PCL (PCFC) copolymer were prepared by in situ combination method. Firstly, the PCFC copolymer was synthesized by ring-opening polymerization of epsilon-caprolactone initiated by Pluronic (PEG-PPG-PEG); Secondly, n-HA powder were combined with PCFC to form polymeric composites in the presence of hexamethylene diisocyanate (HDI). The obtained composites were characterized by 1H-NMR, FTIR, XRD, TEM, SEM, DTA/TGA, and tensile testing. The results revealed that n-HA could be dispersed into polymer matrix uniformly, and the n-HA/PCFC composite showed great mechanical properties when the content of n-HA was 10 wt%. The microstructure and thermal properties of the composites were discussed in the paper too. The experimental results suggested that this polymeric nanocomposite might have great potential application in the field of tissue engineering.

The ATP-binding cassette transporter OsPDR1 regulates plant growth and pathogen resistance by affecting jasmonates biosynthesis in rice.

Jasmonates (JAs) are important regulators of plant growth, development, and defense. ATP-binding cassette (ABC) transporters participate in disease resistance by transporting JAs or antimicrobial secondary metabolites in dicotyledons. Here, we functionally characterized a JAs-inducible rice gene (OsPDR1) that encodes a member of the pleiotropic drug resistance (PDR) subfamily of ABC transporters. By affecting JAs biosynthesis, overexpression of OsPDR1 resulted in constitutive activation of defense-related genes and enhanced resistance to bacterial blight, whereas its mutation decreased pathogen resistance. In addition, overexpression and mutation of OsPDR1 resulted in decreased and increased plant growth at seedling stage, respectively, but eventually led to decreased grain yield. OsPDR1 encodes three splice isoforms, of which OsPDR1.2 and OsPDR1.3 contain a conserved glutamate residue in the "ENI-motif" of the first nucleotide-binding domain, while OsPDR1.1 does not. The three OsPDR1 transcripts are developmentally controlled and differentially regulated by JAs and pathogen infection. The OsPDR1.2- and OsPDR1.3-overexpressing plants exhibited higher JAs content and stronger growth inhibition and disease resistance than OsPDR1.1-overexpressing plants. These results indicated that alternative splicing affects the function of OsPDR1 gene in regulation of growth, development and disease resistance.

Physiological characterisation and fine mapping of a salt-tolerant mutant in rice (Oryza sativa).

Salt-tolerant mutants are valuable resources for basic and applied research on plant salt tolerance. Here, we report the isolation and characterisation of a salt-tolerant rice (Oryza sativa L.) mutant. This mutant was identified from an ethyl methanesulfonate-induced Nipponbare mutant library, designated as rice salt tolerant 1 (rst1). The rst1 mutant was tolerant to salt stress and showed significantly higher shoot biomass and chlorophyll content, but lower lipid peroxidation and electrolyte leakage under NaCl stress. The improved salt tolerance of this mutant may be due mainly to its enhanced ability to restrict Na+ accumulation in shoots under salt stress conditions. Genetic analysis indicated that the salt tolerance of the rst1 mutant was controlled by a single recessive gene. Quantitative trait locus (QTL) mapping for salt tolerance was performed using an F2 population of rst1×Peiai 64. Two QTLs were detected, in which the locus on chromosome 6 was determined to be the candidate locus of the rst1 gene. The rst1 locus was subsequently shown to reside within a 270.4-kb region defined by the markers IM29432 and IM29702. This result will be useful for map-based cloning of the rst1 gene and for marker-assisted breeding for salt tolerance in rice.

Synthesis of a novel biodegradable poly(ester amine) (PEAs) copolymer based on low-molecular-weight polyethyleneimine for gene delivery.

In this paper, a novel biodegradable poly(ester amine) (PEA) copolymer was successfully prepared from low-molecular-weight polyethyleneimine (PEI, Mn=1800) and poly(epsilon-caprolactone)-Pluronic-poly(epsilon-caprolactone) (PCFC) copolymers. According to the results of agarose gel electrophoresis, particle sizes and zeta potential measurement and transfection efficiency, these PEA copolymers showed great ability to condense plasmid DNA effectively into nano-complexes with small particle size (< or =200 nm) and moderate zeta potential (> or =12 mV) at proper polymeric carrier/DNA weight ratio. Compared with low-molecular-PEI (Mn=1800), the obtained PEAs exhibited higher transfection efficiency as well as lower cytotoxicity. These results indicated that such PEAs might have great potential application in gene delivery system.