OsEIL2 balances rice immune responses against (hemi)biotrophic and necrotrophic pathogens via the salicylic acid and jasmonic acid synergism.

Plants typically activate distinct defense pathways against various pathogens. Heightened resistance to one pathogen often coincides with increased susceptibility to another pathogen. However, the underlying molecular basis of this antagonistic response remains unclear. Here, we demonstrate that mutants defective in the transcription factor ETHYLENE-INSENSITIVE 3-LIKE 2 (OsEIL2) exhibited enhanced resistance to the biotrophic bacterial pathogen Xanthomonas oryzae pv oryzae and to the hemibiotrophic fungal pathogen Magnaporthe oryzae, but enhanced susceptibility to the necrotrophic fungal pathogen Rhizoctonia solani. Furthermore, necrotroph-induced OsEIL2 binds to the promoter of OsWRKY67 with high affinity, leading to the upregulation of salicylic acid (SA)/jasmonic acid (JA) pathway genes and increased SA/JA levels, ultimately resulting in enhanced resistance. However, biotroph- and hemibiotroph-induced OsEIL2 targets OsERF083, resulting in the inhibition of SA/JA pathway genes and decreased SA/JA levels, ultimately leading to reduced resistance. Our findings unveil a previously uncharacterized defense mechanism wherein two distinct transcriptional regulatory modules differentially mediate immunity against pathogens with different lifestyles through the transcriptional reprogramming of phytohormone pathway genes.

Identification of two novel rice S genes through combination of association and transcription analyses with gene-editing technology.

Traditional rice blast resistance breeding largely depends on utilizing typical resistance (R) genes. However, the lack of durable R genes has prompted rice breeders to find new resistance resources. Susceptibility (S) genes are potential new targets for resistance genetic engineering using genome-editing technologies, but identifying them is still challenging. Here, through the integration of genome-wide association study (GWAS) and transcriptional analysis, we identified two genes, RNG1 and RNG3, whose polymorphisms in 3'-untranslated regions (3'-UTR) affected their expression variations. These polymorphisms could serve as molecular markers to identify rice blast-resistant accessions. Editing the 3'-UTRs using CRISPR/Cas9 technology affected the expression levels of two genes, which were positively associated with rice blast susceptibility. Knocking out either RNG1 or RNG3 in rice enhanced the rice blast and bacterial blight resistance, without impacting critical agronomic traits. RNG1 and RNG3 have two major genotypes in diverse rice germplasms. The frequency of the resistance genotype of these two genes significantly increased from landrace rice to modern cultivars. The obvious selective sweep flanking RNG3 suggested it has been artificially selected in modern rice breeding. These results provide new targets for S gene identification and open avenues for developing novel rice blast-resistant materials.

UIEOGP: an underwater image enhancement method based on optical geometric properties.

Due to the inconsistent absorption and scattering effects of different wavelengths of light, underwater images often suffer from color casts, blurred details, and low visibility. To address this image degradation problem, we propose a robust and efficient underwater image enhancement method named UIEOGP. It can be divided into the following three steps. First, according to the light attenuation effect presented by Lambert Beer's law, combined with the variance change after attenuation, we estimate the depth of field in the underwater image. Then, we propose a local-based color correction algorithm to address the color cast issue in underwater images, employing the statistical distribution law. Finally, drawing inspiration from the law of light propagation, we propose detail enhancement algorithms, each based on the geometric properties of circles and ellipses, respectively. The enhanced images produced by our method feature vibrant colors, improved contrast, and sharper detail. Extensive experiments show that our method outperforms current state-of-the-art methods. In further experiments, we found that our method is beneficial for downstream tasks of underwater image processing, such as the detection of keypoints and edges in underwater images.

Genome-wide association study identifies an NLR gene that confers partial resistance to Magnaporthe oryzae in rice.

Because of the frequent breakdown of major resistance (R) genes, identification of new partial R genes against rice blast disease is an important goal of rice breeding. In this study, we used a core collection of the Rice Diversity Panel II (C-RDP-II), which contains 584 rice accessions and are genotyped with 700 000 single-nucleotide polymorphism (SNP) markers. The C-RDP-II accessions were inoculated with three blast strains collected from different rice-growing regions in China. Genome-wide association study identified 27 loci associated with rice blast resistance (LABRs). Among them, 22 LABRs were not associated with any known blast R genes or QTLs. Interestingly, a nucleotide-binding site leucine-rich repeat (NLR) gene cluster exists in the LABR12 region on chromosome 4. One of the NLR genes is highly conserved in multiple partially resistant rice cultivars, and its expression is significantly up-regulated at the early stages of rice blast infection. Knockout of this gene via CRISPR-Cas9 in transgenic plants partially reduced blast resistance to four blast strains. The identification of this new non-strain specific partial R gene, tentatively named rice blast Partial Resistance gene 1 (PiPR1), provides genetic material that will be useful for understanding the partial resistance mechanism and for breeding durably resistant cultivars against blast disease of rice.

Achieving minimal residual disease-negative by multiparameter flow cytometry may ameliorate a poor prognosis in MM patients with high-risk cytogenetics: a retrospective single-center analysis.

The aim of our study was to evaluate the prognostic impact of minimal residual disease (MRD) and high-risk cytogenetics (HRCs) on outcomes in multiple myeloma (MM) patients. We applied multiparameter flow cytometry (MFC) to detect MRD in 123 consecutive patients diagnosed with MM for the first time who achieved very good partial remission (VGPR) or better after bortezomib or thalidomide-based induction therapy. Moreover, we examined the cytogenetic features of MM patients using magnetic-activated cell sorting and interphase fluorescence in situ hybridization (MACS-iFISH) at diagnosis. In all 123 MM patients, progression-free survival (PFS) and overall survival (OS) were better in the MRD- group (n = 31) than in the MRD+ group (n = 92) (median PFS: not reached (NR) vs. 26 months (m), P = 0.0002; 4-year OS, 91.7% vs. 66.3%, P = 0.008). PFS and OS were significantly shorter for each increase of one log per MRD level (P < 0.0001 and P = 0.001). The median PFS of the four groups according to the ratio of aberrant plasma cells (less than 0.01%, 0.01-0.1%, 0.1-1%, and more than 1%) were NR, 37 m, 26 m, and 15 m, respectively, and the 4-year OS rates were 91.7%, 69.3%, 76.1%, and 54.0%, respectively. In addition, our results show that PFS and OS were better for the standard-risk cytogenetic (SRC) patients than the HRC patients (median PFS: NR vs. 26 m, P = 0.004; 3-year OS: 95.8% vs. 76.0%, P = 0.006). The independent predictors of PFS were HRC and MRD+, which had hazard ratios of 1.901 (95% CI 1.094-3.303) and 3.486 (95% CI 1.449-8.386), respectively; while those for OS were an LDH level ≥ 250 U/L, HRC, and MRD+, which had hazard ratios of 2.789 (95% CI 1.080-7.199), 2.697 (95% CI 1.053-6.907), and 7.714 (95% CI 1.040-57.227), respectively. Furthermore, for SRC patients or HRC patients, PFS and OS were all longer in MRD- than in MRD+ patients. Strikingly, there was no significant difference in PFS or OS between the MRD-HRC and MRD+SRC groups (median PFS 45 vs. 34 m, P = 0.300; 4-year OS 100% vs. 83.6%, P = 0.196). PFS was superior in MRD-SRC than in MRD-HRC (NR vs. 45 m, P = 0.035); however, there was no significant difference in the 4-year OS between MRD-SRC and MRD-HRC (87.5% vs 100%, P = 0.480). MRD+ and HRCs were both independent prognostic factors in MM patients. Moreover, achieving MRD- may ameliorate a poor prognosis in MM patients with HRCs.

Priming effect of root-applied silicon on the enhancement of induced resistance to the root-knot nematode Meloidogyne graminicola in rice.

BACKGROUND: Silicon (Si) can confer plant resistance to both abiotic and biotic stress. In the present study, the priming effect of Si on rice (Oryza sativa cv Nipponbare) against the root-knot nematode Meloidogyne graminicola and its histochemical and molecular impact on plant defense mechanisms were evaluated. RESULTS: Si amendment significantly reduced nematodes in rice roots and delayed their development, while no obvious negative effect on giant cells was observed. Increased resistance in rice was correlated with higher transcript levels of defense-related genes (OsERF1, OsEIN2 and OsACS1) in the ethylene (ET) pathway. Si amendment significantly reduced nematode numbers in rice plants with enhanced ET signaling but had no effect in plants deficient in ET signaling, indicating that the priming effects of Si were dependent on the ET pathway. A higher deposition of callose and accumulation of phenolic compounds were observed in rice roots after nematode attack in Si-amended plants than in the controls. CONCLUSION: These findings indicate that the priming effect may partially depend on the production of phenolic compounds and hydrogen peroxide. Further research is required to model the ethylene signal transduction pathway that occurs in the Si-plant-nematode interaction system and gain a better understanding of Si-induced defense in rice.

Three new isobenzofuranone derivatives from the fruiting bodies of Hericium erinaceus.

Three new isobenzofuranone derivatives erinaceolactones D-F (1-3), together with four known ones (4-7), were isolated from the fruiting bodies of Hericium erinaceus. Their structures were determined on the basis of comprehensive spectroscopic analyses including UV, 1D, 2D NMR and HR-TOF-MS. The absolute configuration of erinaceolactone D (1) and erinaceolactone E (2) were assigned by comparing their specific rotation with those of analogs in literatures. The four known compounds were isomers with each other and were isolated simultaneously for the first time.

Two new isobenzofuranone derivatives from the fruiting bodies of Hericium erinaceus.

Two new isobenzofuranone derivatives erinaceolactones G and H (1 and 2) were isolated from the ethanolic extract of fruiting bodies of Hericium erinaceus. Their structures were characterized on the basis of spectroscopic evidences. Compound 2 was suggested to be racemic by specific rotation, which was resolved by chiral HPLC into enantiomers.

Computational Discovery of High-Temperature Ferromagnetic Semiconductor Monolayer H-MnN2.

In the past few years, two-dimensional (2D) high-temperature ferromagnetic semiconductor (FMS) materials with novelty and excellent properties have attracted much attention due to their potential in spintronics applications. In this work, using first-principles calculations, we predict that the H-MnN2 monolayer with the H-MoS2-type structure is a stable intrinsic FMS with an indirect band gap of 0.79 eV and a high Curie temperature (Tc) of 380 K. The monolayer also has a considerable in-plane magnetic anisotropy energy (IMAE) of 1005.70 µeV/atom, including a magnetic shape anisotropy energy induced by the dipole-dipole interaction (shape-MAE) of 168.37 µeV/atom and a magnetic crystalline anisotropy energy resulting from spin-orbit coupling (SOC-MAE) of 837.33 µeV/atom. Further, based on the second-order perturbation theory, its in-plane SOC-MAE of 837.33 µeV/atom is revealed to mainly derive from the couplings of Mn-dxz,dyz and Mn-dx2-y2,dxy orbitals through Lz in the same spin channel. In addition, the biaxial strain and carrier doping can effectively tune the monolayer's magnetic and electronic properties. Such as, under the hole and few electrons doping, the transition from semiconductor to half-metal can be realized, and its Tc can go up to 520 and 620 K under 5% tensile strain and 0.3 hole doping, respectively. Therefore, our research will provide a new, promising 2D FMS for spintronics devices.

The F-box protein OsFBX156 positively regulates rice defence against the blast fungus Magnaporthe oryzae by mediating ubiquitination-dependent degradation of OsHSP71.1.

F-box protein is a subunit of the SCF (SKP1-CUL1-F-box protein) E3 ubiquitin ligase complex, which plays a critical role in regulating different pathways in plant immunity. In this study, we identified the rice (Oryza sativa) F-box protein OsFBX156, which targets the heat shock protein 70 (OsHSP71.1) to regulate resistance to the rice blast fungus Magnaporthe oryzae. Overexpression of OsFBX156 or knockout of OsHSP71.1 in rice resulted in the elevation of pathogenesis-related (PR) genes and an induction burst of reactive oxygen species (ROS) after flg22 and chitin treatments, thereby enhancing resistance to M. oryzae. Furthermore, OsFBX156 can promote the degradation of OsHSP71.1 through the 26S proteasome pathway. This study sheds lights on a novel mechanism wherein the F-box protein OsFBX156 targets OsHSP71.1 for degradation to promote ROS production and PR gene expression, thereby positively regulating rice innate immunity.

Antagonistic control of rice immunity against distinct pathogens by the two transcription modules via salicylic acid and jasmonic acid pathways.

Although the antagonistic effects of host resistance against biotrophic and necrotrophic pathogens have been documented in various plants, the underlying mechanisms are unknown. Here, we investigated the antagonistic resistance mediated by the transcription factor ETHYLENE-INSENSITIVE3-LIKE 3 (OsEIL3) in rice. The Oseil3 mutant confers enhanced resistance to the necrotroph Rhizoctonia solani but greater susceptibility to the hemibiotroph Magnaporthe oryzae and biotroph Xanthomonas oryzae pv. oryzae. OsEIL3 directly activates OsERF040 transcription while repressing OsWRKY28 transcription. The infection of R. solani and M. oryzae or Xoo influences the extent of binding of OsEIL3 to OsWRKY28 and OsERF040 promoters, resulting in the repression or activation of both salicylic acid (SA)- and jasmonic acid (JA)-dependent pathways and enhanced susceptibility or resistance, respectively. These results demonstrate that the distinct effects of plant immunity to different pathogen types are determined by two transcription factor modules that control transcriptional reprogramming and the SA and JA pathways.

Graphene-based anticancer nanosystem and its biosafety evaluation using a zebrafish model.

In this paper, a facile strategy to develop graphene-based delivery nanosystems for effective drug loading and sustained drug release was proposed and validated. Specifically, biocompatible naphthalene-terminated PEG (NP) and anticancer drugs (curcumin or doxorubicin (DOX)) were simultaneously integrated onto oxidized graphene (GO), leading to self-assembled, nanosized complexes. It was found that the oxidation degree of GO had a significant impact on the drug-loading efficiency and the structural stability of nanosystems. Interestingly, the nanoassemblies resulted in more effective cellular entry of DOX in comparison with free DOX or DOX-loaded PEG-polyester micelles at equivalent DOX dose, as demonstrated by confocal microscopy studies. Moreover, the nanoassemblies not only exhibited a sustained drug release pattern without an initial burst release, but also significantly improved the stability of formulations which were resistant to drug leaking even in the presence of strong surfactants such as aromatic sodium benzenesulfonate (SBen) and aliphatic sodium dodecylsulfonate (SDS). In addition, the nanoassemblies without DOX loading showed negligible in vitro cytotoxicity, whereas DOX-loaded counterparts led to considerable toxicity against HeLa cells. The DOX-mediated cytotoxicity of the graphene-based formulation was around 20 folds lower than that of free DOX, most likely due to the slow DOX release from complexes. A zebrafish model was established to assess the in vivo safety profile of curcumin-loaded nanosystems. The results showed they were able to excrete from the zebrafish body rapidly and had nearly no influence on the zebrafish upgrowth. Those encouraging results may prompt the advance of graphene-based nanotherapeutics for biomedical applications.

Design, synthesis and potent cytotoxic activity of novel podophyllotoxin derivatives.

Twenty new acyl thiourea derivatives of podophyllotoxin and 4'-demethylepipodophyllotoxin were prepared and screened for their cytotoxicity against four human tumor cell lines, A-549, DU-145, KB, and KBvin. With IC50 values of 0.098-1.13 µM, compounds 13b, 13c, and 13o displayed much better cytotoxic activity than the control etoposide. Most importantly, 13b and 13o exhibited promising cytotoxicity against the drug resistant tumor cell line KBvin with IC50 values of 0.098 and 0.13 µM, respectively, while etoposide lost activity completely. Structure-activity relationship (SAR) correlations of the new derivatives have been established. Compounds 13b and 13o merit further development as a new generation of epipodophyllotoxin-derived antitumor clinical trial candidates.

Effects of Cycloplegic Agents on Ocular Parameters in Children with Myopia and Hyperopia.

Background: To study the effect of cycloplegia on ocular parameters in children with myopia and hyperopia. Methods: Forty-two myopia and forty-four hyperopia eyes in children between 5 and 10 years of age were included. Measurements were taken before and after cycloplegia using 1% atropine sulfate ointment. The ocular parameters included central corneal thickness (CCT), corneal curvature (CC), anterior chamber depth (ACD), pupil diameter (PD), axial length (AL), and central retinal thickness (CRT). Results: There was no significant difference in CCT, CC, and CRT between the two groups without cycloplegia, but the ACD of the myopia (3.64 ± 0.28 mm) group was significantly higher than that of hyperopia (3.40 ± 0.24 mm; t = -4.522; P < 0.0001). The average PD of the myopia (4.85 ± 0.87 mm) group was significantly smaller than that of the hyperopia group (5.47 ± 1.15 mm; t = 2.903; P < 0.0046). The average AL of myopia (24.25 ± 0.77 mm) was significantly higher than that of hyperopia (21.73 ± 1.24 mm; t = 12.084; P < 0.0001). However, it was found that the average PD of myopia (7.68 ± 0.51 mm) was significantly larger than that of hyperopia (7.41 ± 0.57 mm; t = 2.364; P=0.0202) under cycloplegia. As for the changes in refractive factors before and after cycloplegia, deepened ACD and enlarged PD were noted in both the groups after cycloplegia. Conclusions: Cycloplegia not only affects ACD and PD but also leads to the reversal of PD differences between the two groups. Cycloplegia effects enabled us to study changes in all known ocular parameters in a short period.

Mitochondrial functions in plant immunity.

Mitochondria are energy factories of cells and are important for intracellular interactions with other organelles. Emerging evidence indicates that mitochondria play essential roles in the response to pathogen infection. During infection, pathogens deliver numerous enzymes and effectors into host cells, and some of these effectors target mitochondria, altering mitochondrial morphology, metabolism, and functions. To defend against pathogen attack, mitochondria are actively involved in changing intracellular metabolism, hormone-mediated signaling, and signal transduction, producing reactive oxygen species and reactive nitrogen species and triggering programmed cell death. Additionally, mitochondria coordinate with other organelles to integrate and amplify diverse immune signals. In this review, we summarize recent advances in understanding how mitochondria function in plant immunity and how pathogens target mitochondria for host defense suppression.

An ORFeome of rice E3 ubiquitin ligases for global analysis of the ubiquitination interactome.

BACKGROUND: Ubiquitination is essential for many cellular processes in eukaryotes, including 26S proteasome-dependent protein degradation, cell cycle progression, transcriptional regulation, and signal transduction. Although numerous ubiquitinated proteins have been empirically identified, their cognate ubiquitin E3 ligases remain largely unknown. RESULTS: Here, we generate a complete ubiquitin E3 ligase-encoding open reading frames (UbE3-ORFeome) library containing 98.94% of the 1515 E3 ligase genes in the rice (Oryza sativa L.) genome. In the test screens with four known ubiquitinated proteins, we identify both known and new E3s. The interaction and degradation between several E3s and their substrates are confirmed in vitro and in vivo. In addition, we identify the F-box E3 ligase OsFBK16 as a hub-interacting protein of the phenylalanine ammonia lyase family OsPAL1-OsPAL7. We demonstrate that OsFBK16 promotes the degradation of OsPAL1, OsPAL5, and OsPAL6. Remarkably, we find that overexpression of OsPAL1 or OsPAL6 as well as loss-of-function of OsFBK16 in rice displayed enhanced blast resistance, indicating that OsFBK16 degrades OsPALs to negatively regulate rice immunity. CONCLUSIONS: The rice UbE3-ORFeome is the first complete E3 ligase library in plants and represents a powerful proteomic resource for rapid identification of the cognate E3 ligases of ubiquitinated proteins and establishment of functional E3-substrate interactome in plants.

Re-evaluation of pathogens causing Valsa canker on apple in China.

Valsa canker is a destructive disease on apple that causes serious economic losses in eastern Asia. In the present study fungal isolates from cankered apple and pear bark were examined and compared with morphology and rDNA-ITS sequences. Valsa mali was confirmed to be an independent species and a causal pathogen of Valsa canker on apple and pear in China. It was the predominant species (96.7% of isolates) on apple and was complemented by V. malicola (3.3% of isolates). Significant intraspecific genetic differentiation was detected in V. mali with two varieties recognized, V. mali var. mali occurring exclusively on apple and V. mali var. pyri occurring on both apple and pear. Results from genetic analysis and cross-inoculation tests provided support for the hypothesis that host preference probably catalyzed such genetic changes within the pathogen populations.

Association Mapping and Functional Analysis of Rice Cold Tolerance QTLs at the Bud Burst Stage.

Cold tolerance at the bud burst stage (CTB) is a key trait for direct-seeded rice. Although quantitative trait loci (QTL) affecting CTB in rice have been mapped using traditional linkage mapping and genome-wide association study (GWAS) methods, the underlying genes remain unknown. In this study, we evaluated the CTB phenotype of 339 cultivars in the Rice Diversity Panel II (RDP II) collection. GWAS identified four QTLs associated with CTB (qCTBs), distributed on chromosomes 1-3. Among them, qCTB-1-1 overlaps with Osa-miR319b, a known cold tolerance micro RNA gene. The other three qCTBs have not been reported. In addition, we characterised the candidate gene OsRab11C1 for qCTB-1-2 that encodes a Rab protein belonging to the small GTP-binding protein family. Overexpression of OsRab11C1 significantly reduced CTB, while gene knockout elevated CTB as well as cold tolerance at the seedling stage, suggesting that OsRab11C1 negatively regulates rice cold tolerance. Molecular analysis revealed that OsRab11C1 modulates cold tolerance by suppressing the abscisic acid signalling pathway and proline biosynthesis. Using RDP II and GWAS, we identified four qCTBs that are involved in CTB and determined the function of the candidate gene OsRab11C1 in cold tolerance. Our results demonstrate that OsRab11C1 is a negative regulator of cold tolerance and knocking out of the gene by genome-editing may provide enhanced cold tolerance in rice.

New amphiphilic carriers forming pH-sensitive nanoparticles for nucleic acid delivery.

Amphiphilic lipids are promising for efficient intracellular delivery of nucleic acids. In this study, two new amphiphilic carriers, EKHCO and EHHKCO, were designed and synthesized as multifunctional carriers for efficient intracellular delivery of nucleic acids. The critical micelle concentrations of EKHCO and EHHKCO were 9.50 and 6.87 microM, respectively. Dynamic light scattering showed that the surfactants complexed with plasmid DNA and siRNA to form stable nanoparticles at the concentrations below their critical micelle concentrations. The nanoparticles of the surfactants with pDNA and siRNA exhibited pH-sensitive hemolysis against rat red blood cells when the pH decreased from 7.4 to 5.5, the endosomal-lysosomal pH. The nanoparticles of EHHKCO showed more concentration-dependent pH sensitivity than those of EKHCO. The EHHKCO and EKHCO nanoparticles of both pNDA and siRNA exhibited low cytotoxicity of at physiological pH. Both EKHCO and EHHKCO resulted in high intracellular uptake of pDNA and siRNA. EKHCO and EHHKCO resulted in relatively lower luciferase expression efficiency in U87 cells than DOTAP but produced a much higher percentage of GFP expression in the transfected cells than DOTAP. Both EKHCO and EHHKCO mediated much higher gene silencing efficiency of luciferase and green fluorescence protein (GFP) than DOTAP. The surfactants were more effective for intracellular siRNA delivery than intracellular delivery of plasmid DNA. The pH-sensitive amphiphilic carriers are promising multifunctional carriers for intracellular delivery of nucleic acids.