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Arabidopsis RESISTANCE TO POWDERY MILDEW 8.2 (RPW8.2) is specifically induced by the powdery mildew (PM) fungus (Golovinomyces cichoracearum) in the infected epidermal cells to activate immunity. However, the mechanism of RPW8.2-induction is not well understood. Here, we identify a G. cichoracearum effector that interacts with RPW8.2, named Gc-RPW8.2 interacting protein 1 (GcR8IP1), by a yeast two-hybrid screen of an Arabidopsis cDNA library. GcR8IP1 physically associated with RPW8.2 with its RING finger domain that is essential and sufficient for the association. GcR8IP1 was secreted and translocated into the nucleus of host cell infected with PM. Association of GcR8IP1 with RPW8.2 led to an increase of RPW8.2 in the nucleus. In turn, the nucleus-localised RPW8.2 promoted the activity of the RPW8.2 promoter, resulting in transcriptional self-amplification of RPW8.2 to boost immunity at infection sites. Additionally, ectopic expression or host-induced gene silencing of GcR8IP1 supported its role as a virulence factor in PM. Altogether, our results reveal a mechanism of RPW8.2-dependent defense strengthening via altered partitioning of RPW8.2 and transcriptional self-amplification triggered by a PM fungal effector, which exemplifies an atypical form of effector-triggered immunity.

Rice production is threatened by multiple pathogens. Breeding cultivars with broad-spectrum disease resistance is necessary to maintain and improve crop production. Previously we found that overexpression of miR160a enhanced rice blast disease resistance. However, it is unclear whether miR160a also regulates resistance against other pathogens, and what the downstream signaling pathways are. Here, we demonstrate that miR160a positively regulates broad-spectrum resistance against the causative agents of blast, leaf blight and sheath blight in rice. Mutations of miR160a-targeted Auxin Response Factors result in different alteration of resistance conferred by miR160a. miR160a enhances disease resistance partially by suppressing ARF8, as mutation of ARF8 in MIM160 background partially restores the compromised resistance resulting from MIM160. ARF8 protein binds directly to the promoter and suppresses the expression of WRKY45, which acts as a positive regulator of rice immunity. Mutation of WRKY45 compromises the enhanced blast resistance and bacterial leaf blight resistance conferred by arf8 mutant. Overall, our results reveal that a microRNA coordinates rice broad-spectrum disease resistance by suppressing multiple target genes that play different roles in disease resistance, and uncover a new regulatory pathway mediated by the miR160a-ARF8 module. These findings provide new resources to potentially improve disease resistance for breeding in rice.

Abstract: Mitochondria regulate a range of important physiological and biochemical cellular processes including apoptotic cell death, energy production, calcium homeostasis, oxidative stress, and lipid metabolism. Given their role as the ‘engines’ of cells, their dysfunction is associated with a variety of disease states. Exploring the relationship between mitochondrial function and disease can reveal the mechanism(s) of drug activity and disease pathology. In this review, we summarized the methods of evaluating the structure and function of mitochondria, including the morphology, membrane fluidity, membrane potential, opening of the membrane permeability transition pore, inner membrane permeabilization, mitochondrial dynamics, mitophagy, oxidative stress, energy metabolism-related enzymes, apoptotic pathway related proteins, calcium concentration, DNA copy number, oxygen consumption, β-oxidation-related genes and proteins, cardiolipin content, and adenosine triphosphate content. We believe that the information presented in this review will help explore the pathological processes of mitochondria in the occurrence and development of diseases, as well as the activity and mechanism of drugs, and the discovery of new drugs.

MicroRNAs (miRNAs) act as regulators of plant development and multiple stress responses. Here we demonstrate that the rice miR171b-SCL6-IIs module regulates the balance between blast resistance, grain yield, and flowering. miR171b-overexpressing rice plants (OX171b) displayed increased rice blast resistance accompanied with enhanced defense responses and late heading, whereas blocking miR171b expression in rice (MIM171) led to greater susceptibility to blast disease, associated with compromised defense responses and early heading. Either overexpressing or silencing of miR171b significantly affected plant height and number of filled seeds per panicle (seed-setting rate), resulting in decreased grain yield. miR171b targets SCL6-IIa, SCL6-IIb, and SCL6-IIc, whose expression was suppressed in OX171b but increased in MIM171. Mutants of SCL6-IIa, SCL6-IIb, and SCL6-IIc all displayed phenotypes like that of OX171b, including markedly increased blast disease resistance, slightly decreased grain yield, and delayed flowering. Amounts of miR171b increased gradually in leaves during the vegetative stage but decreased gradually in panicles during the reproductive stage, whereas SCL6-IIs displayed the reverse expression pattern. Together, these results suggest that the expression of miR171b was time- and space-dependent during the rice growth period and regulated the balance between rice blast disease resistance, grain yield, and flowering via SCL6-IIs, and that appropriate accumulation of miR171b is essential for rice development.

microRNAs act as fine-tuners in the regulation of plant growth and resistance against biotic and abiotic stress. Here we demonstrate that rice miR1432 fine-tunes yield and blast disease resistance via different modules. Overexpression of miR1432 leads to compromised resistance and decreased yield, whereas blocking miR1432 using a target mimic of miR1432 results in enhanced resistance and yield. miR1432 suppresses the expression ofLOC_Os03g59790, which encodes an EF-hand family protein 1 (OsEFH1). Overexpression ofOsEFH1leads to enhanced rice resistance but decreased grain yield. Further study revealed that miR1432 andOsEFH1are differentially responsive to chitin, a fungus-derived pathogen/microbe-associated molecular pattern (PAMP/MAMP). Consistently, blocking miR1432 or overexpression ofOsEFH1improves chitin-triggered immunity responses. In contrast, overexpression ofACOT, another target gene regulating rice yield traits, has no significant effects on rice blast disease resistance. Altogether, these results indicate that miR1432 balances yield and resistance via different target genes, and blocking miR1432 can simultaneously improve yield and resistance.

RESISTANCE TO POWDERY MILDEW 8 (RPW8) defines a unique N-terminal coiled-coil domain of nucleotide-binding and leucine-rich repeat immune receptors required for immune signaling in plants. Arabidopsis RPW8.2 is specifically induced by the powdery mildew (PM) fungus (Golovinomyces cichoracearum) in the infected epidermal cells to activate immunity. The mechanism of RPW8.2-induction is not well understood. Here, we identify aG. cichoracearumfactor delivered to the nucleus of the host cell, named Gc-RPW8.2 interacting protein 1 (GcR8IP1). Ectopic expression of GcR8IP1 in Arabidopsis orNicotiana benthamianasuppressed host immune responses and enhanced susceptibility to PM. Host-induced gene silencing ofGcR8IP1compromised PM infectivity in susceptible Arabidopsis plants. Co-expression of GcR8IP1 with RPW8.2 increased nuclear localization of RPW8.2, which in turn, promoted transcriptional amplification ofRPW8.2. Thus, RPW8.2-dependent defense strengthening is due to altered partitioning of RPW8.2 by an effector of a PM fungus, which exemplifies an atypical form of effector-triggered immunity.

MicroRNA168 (miR168) is a key miRNA that targets Argonaute1 (AGO1), a major component of the RNA-induced silencing complex1,2. Previously, we reported that miR168 expression was responsive to infection by Magnaporthe oryzae, the causal agent of rice blast disease3. However, how miR168 regulates immunity to rice blast and whether it affects rice development remains unclear. Here, we report our discovery that the suppression of miR168 by a target mimic (MIM168) not only improves grain yield and shortens flowering time in rice but also enhances immunity to M. oryzae. These results were validated through repeated tests in rice fields in the absence and presence of rice blast pressure. We found that the miR168–AGO1 module regulates miR535 to improve yield by increasing panicle number, miR164 to reduce flowering time, and miR1320 and miR164 to enhance immunity. Our discovery demonstrates that changes in a single miRNA enhance the expression of multiple agronomically important traits. In rice, it is known that miR168 regulates AGO1. Using a target mimic approach to suppress the microRNA enhances resistance against rice blast disease, increases grain yield and shortens growth period, including in field trials.

Herein, the clinically approved nitrogen mustard, chlorambucil (Chl), is covalently embedded into a poly(N-(2-hydroxypropyl)methacrylamide, HPMA) vector via a hydrolysable ester bond to overcome the shortcomings of Chl as well as to achieve better efficacy. The well-defined poly-prodrug amphiphiles with Chl loading content >10 wt% can form uniform nanoparticles with an average diameter of 200 nm through a macromolecular self-assembly strategy. The detailed structure information and Chl release properties are carefully inspected. Cytotoxicity studies against the HepG2 and MCF-7 cell lines combined with flow cytometry reveal that the poly(HPMA)–Chl conjugate exhibits obvious targeting ability and markedly enhanced antitumor effect compared to the free Chl. After labelling with a fluorescent group, the cell uptake, lysosome escape and distribution in living organs of the poly-prodrug were also studied.

Grain formation is fundamental for crop yield but is vulnerable to abiotic and biotic stresses. Rice grain production is threatened by the false smut fungus Ustilaginoidea virens, which specifically infects rice floral organs, disrupting fertilization and seed formation. However, little is known about the molecular mechanisms of the U. virens-rice interaction and the genetic basis of floral resistance. Here, we report that U. virens secretes a cytoplasmic effector, UvCBP1, to facilitate infection of rice flowers. Mechanistically, UvCBP1 interacts with the rice scaffold protein OsRACK1A and competes its interaction with the reduced nicotinamide adenine dinucleotide phosphate oxidase OsRBOHB, leading to inhibition of reactive oxygen species (ROS) production. Although the analysis of natural variation revealed no OsRACK1A variants that could avoid being targeted by UvCBP1, expression levels of OsRACK1A are correlated with field resistance against U. virens in rice germplasm. Overproduction of OsRACK1A restores the OsRACK1A-OsRBOHB association and promotes OsRBOHB phosphorylation to enhance ROS production, conferring rice floral resistance to U. virens without yield penalty. Taken together, our findings reveal a new pathogenic mechanism mediated by an essential effector from a flower-specific pathogen and provide a valuable genetic resource for balancing disease resistance and crop yield.

Poly-GA, a dipeptide repeat protein unconventionally translated from GGGGCC (G4C2) repeat expansions in C9orf72, is abundant in C9orf72-related amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) (C9orf72-ALS/FTD). Although the poly-GA aggregates have been identified in C9orf72-ALS/FTD neurons, the effects on UPS (ubiquitin-proteasome system) and autophagy and their exact molecular mechanisms have not been fully elucidated.Herein, our in vivo experiments indicate that the mice expressing ploy-GA with 150 repeats instead of 30 repeats exhibit significant aggregates in cells. Mice expressing 150 repeats ploy-GA shows behavioral deficits and activates autophagy in the brain. In vitro findings suggest that the poly-GA aggregates influence proteasomal by directly binding proteasome subunit PSMD2. Subsequently, the poly-GA aggregates activate phosphorylation and ubiquitination of p62 to recruit autophagosomes. Ultimately, the poly-GA aggregates lead to compensatory activation of autophagy. In vivo studies further reveal that rapamycin (autophagy activator) treatment significantly improves the degenerative symptoms and alleviates neuronal injury in mice expressing 150 repeats poly-GA. Meanwhile, rapamycin administration to mice expressing 150 repeats poly-GA reduces neuroinflammation and aggregates in the brain.In summary, we elucidate the relationship between poly-GA in the proteasome and autophagy: when poly-GA forms complexes with the proteasome, it recruits autophagosomes and affects proteasome function. Our study provides support for further promoting the comprehension of the pathogenesis of C9orf72, which may bring a hint for the exploration of rapamycin for the treatment of ALS/FTD.

Background Poly-GA, a dipeptide repeat protein unconventionally translated from GGGGCC repeat expansions in C9orf72, is abundant in C9orf72-related amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Although the poly-GA aggregates have been identified in C9orf72-ALS/FTD neurons, the effects on UPS and autophagy, and their exact molecular mechanisms have not been fully elucidated. Methods We generated poly-GA mice,and treated poly-GA mice for 90 days by intraperitoneal injection rapamycin (4 mg/kg) every 2 days until behavioral analysis. GFAP (an astrogliosis marker), Iba1 (a microgliosis marker), GFP, p62, p-p62 (S349), p-p62 (S403) and LC3 proteins expression were quantified in brain tissues by immunohistochemistry, immunofluorescence, immunoblotting. These results were validated in vitro by protein mass spectrometry, co-immunoprecipitation and immunofluorescence. Results Herein, our in vivo experiments show that ploy-GA mice expressing 150 repeats but not 30 repeats GA exhibit significant aggregates in cells, behavioral deficits, and activate autophagy in the brain, in vitro results demonstrate that aggregated poly-GA induces proteasomal stress through directly binding proteasome subunit PSMD2 to recruit proteasome and impair its function, subsequently activates phosphorylation and ubiquitination of p62 to recruit autophagosome, ultimately leading to compensatory autophagy activation. While rapamycin treatment significantly improves the degenerative symptoms of mice expressing 150 repeats poly-GA, relieves neuronal injury and reduces neuroinflammation and aggregates in the brain. Conclusion In summary, we clarify for the first time the relationship of poly-GA between proteasome and autophagy: poly-GA aggregates recruit autophagosomes only when it forms complex with the proteasome and causes proteasomal stress. Our study provides support for further promoting the comprehension about the pathogenesis of C9orf72 and may bring a hint for the therapy.

The receptor-like kinase (RLK) FERONIA functions in immunity in Arabidopsis. Here, we systemically screened rice RLK genes encoding FERONIA-like receptor (FLRs) that may be involved in rice-Magnaporthe oryzae interaction. The expression of 16 FLR genes was examined in response to the infection of M. oryzae in different rice varieties. For each FLR gene, at least two independent mutants were generated by CRISPR/Cas9 gene-editing technology in rice variety Zhonghua 11 (ZH11). Blast disease assay identified that the mutants of FLR1 and FLR13 showed increased susceptibility, whereas the mutants of FLR2 and FLR11 displayed enhanced resistance. Consistently, the mutant of FLR1 enhanced, but the mutant of FLR2 delayed the M. oryzae infection progress, which might be associated with the altered expression of defense-related genes. Together, these data indicate that at least 4 FLR genes are involved in rice-M. oryzae interaction and thus are potentially valuable in blast disease resistance.

MicroRNAs (miRNAs) are known to fine-tune growth, development, and stress-induced responses. Osa-miR1873 is a rice-specific miRNA targeting LOC_Os05g01790. Here, we show that Osa-miR1873 fine-tunes rice immunity against Magnaporthe oryzae and yield traits via LOC_Os05g01790. Osa-miR1873 was significantly upregulated in a susceptible accession but downregulated in a resistance accession at 24 h post-inoculation (hpi) of M. oryzae. Overexpressing Osa-miR1873 enhanced susceptibility to M. oryzae and compromised induction of defense responses. In contrast, blocking Osa-miR1873 through target mimicry compromised susceptibility to M. oryzae and enhanced induction of defense responses. Altered expression of Osa-miR1873 also resulted in some defects in yield traits, including grain numbers and seed setting rate. Moreover, overexpression of the target gene LOC_Os05g01790 increased rice blast disease resistance but severely penalized growth and yield. Taken together, we demonstrate that Osa-miR1873 fine-tunes the rice immunity-growth trade-off via LOC_Os05g01790, and blocking Osa-miR1873 could improve blast disease resistance without significant yield penalty. Thus, the Osa-miR1873-LOC_Os05g01790 regulatory module is valuable in balancing yield traits and blast resistance.

Objective To review and meta-analyze the efficacy of educational counseling alone in tinnitus. Methods We collected randomized controlled trials (RCTs) adhered to PRISMA guidelines. Analyzed the effect of educational counseling alone versus other forms of therapy (psychological or combination) with RevMan 5.3. Results In nine trials, 582 patients receiving educational counseling alone and 759 patients receiving other psychological or combination therapies. During the 3–6 months follow-up, there was no significant difference in the tinnitus recovery rate between these two groups (OR 0.62, 95% CI 0.34–1.16, P = 0.14; I2 = 71%, P = 0.00, random-effects model). The tinnitus symptom severity rates were also similar during 1–12 months follow-up (mean difference, 3.59, 95% CI −0.56–7.74, P = 0.09) with heterogeneity among studies (I2 = 74%, P = 0.00; random-effects model). Sensitivity analysis indicated that a single trial containing almost 40% of the patients was the cause of heterogeneity. There was no significant change in tinnitus loudness at the 3 months follow-up (OR 0.84, 95% CI 0.42–1.66, P = 0.61), with no significant heterogeneity (I2 = 0%, P = 0.60). Conclusion Educational counseling alone helps to improve tinnitus and related problems, and has the same effect as other psychological or combination therapies. Practice Implications The results of the current analysis may help to develop evidence-based cost-effective treatment(s) for tinnitus, which will be minimally burdensome for the patients.

The pulmonary embolism severity index (PESI) and simplified PESI (sPESI) are recommended to recognize patients with acute pulmonary thromboembolism (PTE) with low prognosis risk, which is of great significance for treatment. This study aims to verify the influence of hypocalcaemia on the prognosis of patients with PTE and to establish a new prognosis assessment model.This is an observational, multicentre study enrolling patients with PTE from February 2010 to June 2020 across 12 Chinese hospitals. Variables in PESI, serum calcium levels and patient survival status as of 5 July 2020 were collected. The area under the curve of the receiver operating characteristic curve, sensitivity, specificity and Youden index were used to evaluate model performance.In the cohort of 4196 patients with PTE, independent associations existed between hypocalcaemia and mid- and long-term mortalities (p 0.05). By including hypocalcaemia, the new 30-day death risk prediction rule, Peking Union Medical College Hospital rule (PUMCH rule), showed significantly higher specificity (0.622 [0.582, 0.661]; p 0.001) than the PESI (0.514 [0.473, 0.554]) and sPESI (0.484 [0.444, 0.525]) and similar sensitivity (0.963 [0.810, 0.999]; p = 0.161) with PESI (0.889 [0.708, 0.976]) and sPESI (0.963 [0.810, 0.999]) in the internal validation cohort. Well-performing predictive validity was also verified on a constructed external validation cohort.Hypocalcaemia is independently associated with mid- and long-term PTE mortalities. The PUMCH rule showed significantly higher specificity than the PESI and sPESI and similar sensitivity, which may be used as a prognostic assessment tool for patients with acute PTE.

Under the background of the Belt and Road Initiative, the exchange of traditional medicine has become inevitable. China and Thailand are amicable neighbors, and the cooperation between the two countries in the field of traditional medicine has become increasingly close in recent years. Nevertheless, on account of the differences in culture, region, politics, economy and so on, the two countries have common features and unique characteristics in the theoretical system of traditional medicine, quality standard control of medicinal materials, research and development and use of medicinal materials. This paper summarizes the similarities and differences as well as the development opportunities of traditional medicine between China and Thailand. The specific content involves the development history, resources, and use of medicinal resources in Thailand, the main achievements and existing problems of modern research of Thai medicine, the spread and development of Chinese medicine in Thailand, and the spread and development of Thai medicine in China. Furthermore, the paper outlines the recent situation of traditional medicine interflow and cooperation between the two countries, and predicts the prospects for cooperation and development of traditional medicine between China and Thailand in the context of the Belt and Road Initiative, especially in the joint research and development and the improvement of quality standards of important medicinal plant varieties commonly used by the two countries and circulated across the border. Through the exchange and mutual learning, we can step up the traditional medicine cooperation between China and Thailand, which will provide advantageous conditions for the safety of medicine use as well as political and social stability between the two countries.

The K-means algorithm is highly sensitive to the initial clustering centers and easily get trapped in a local optimum. To avoid such problems, this paper proposes an improved crossover operator of chromosomes in the genetic algorithm, redefines the calculation method of genetic probability and the natural selection rules, introduces different individual selection mechanisms for the two adjacent generations of chromosomes, and integrates the K-means algorithm into the improved genetic algorithm. Experiment results demonstrate that the improved K-Means algorithm is better than the original genetic algorithm and K-Means algorithm in clustering performance, far better than the bisecting K-means algorithm.

Magnaporthe oryzae is the causative agent of rice blast, a devastating disease in rice worldwide. Based on the gene-for-gene paradigm, resistance (R) proteins can recognize their cognate avirulence (AVR) effectors to activate effector-triggered immunity. AVR genes have been demonstrated to evolve rapidly, leading to breakdown of the cognate resistance genes. Therefore, understanding the variation of AVR genes is essential to the deployment of resistant cultivars harboring the cognate R genes. In this study, we analyzed the nucleotide sequence polymorphisms of eight known AVR genes, namely, AVR-Pita1, AVR-Pii, AVR-Pia, AVR-Pik, AVR-Pizt, AVR-Pi9, AVR-Pib, and AVR-Pi54 in a total of 383 isolates from 13 prefectures in the Sichuan Basin. We detected the presence of AVR-Pik, AVR-Pi54, AVR-Pizt, AVR-Pi9, and AVR-Pib in the isolates of all the prefectures, but not AVR-Pita1, AVR-Pii, and AVR-Pia in at least seven prefectures, indicating loss of the three AVRs. We also detected insertions of Pot3, Mg-SINE, and indels in AVR-Pib, solo-LTR of Inago2 in AVR-Pizt, and gene duplications in AVR-Pik. Consistently, the isolates that did not harboring AVR-Pia were virulent to IRBLa-A, the monogenic line containing Pia, and the isolates with variants of AVR-Pib and AVR-Pizt were virulent to IRBLb-B and IRBLzt-t, the monogenic lines harboring Pib and Piz-t, respectively, indicating breakdown of resistance by the loss and variations of the avirulence genes. Therefore, the use of blast resistance genes should be alarmed by the loss and nature variations of avirulence genes in the blast fungal population in the Sichuan Basin.

Objectives: To study the prevalence of hyperacusis in the general population and the special population, and to determine the effect of population differences on hyperacusis.Methods: The two authors followed a scoping review methodology and screened nearly 30 years of English literature in Pubmed, Web of Science, OVID, and EBSCO. Then, the extracted results of each study were discussed in groups and subgroups.Results: The authors selected 42 pieces of scientific literature that met the requirements, studying a total of 34,796 subjects, including the general population (28,425 subjects), the special occupation population (2,746 subjects), and the patients with concomitant diseases (5,093 subjects). The prevalence was 0.2–17.2% in the general population, 3.8–67% in the special occupation population, and 4.7–95% in the patients with special diseases. It was found that in the general population, the high prevalence occurs in adolescents and older adults. The prevalence of hyperacusis in women is significantly higher than in men. In people with hearing disorders, the prevalence of hyperacusis is significantly higher than in people with normal hearing. Various diseases (such as Williams syndrome, tinnitus, and autism), as well as various occupations (musicians, music students, teachers, and others), have been found to be high risk factors for hyperacusis.Conclusion: The high prevalence of hyperacusis and the large differences between reported prevalence in different studies deserves our great attention. Additionally, in order to increase the comparability of the studies, a standardized set of criteria are needed to study the prevalence of hyperacusis.

MicroRNAs fine-tune plant growth and resistance against multiple biotic and abiotic stresses. The trade-off between biomass and resistance can penalize crop yield. In this study, we have shown that rice miR530 regulates blast disease resistance, yield, and growth period. While the overexpression of miR530 results in compromised blast disease resistance, reduced grain yield, and late maturity, blocking miR530 using a target mimic (MIM530) leads to enhanced resistance, increased grain yield, and early maturity. Further study revealed that the accumulation of miR530 was decreased in both leaves and panicles along with the increase of age. Such expression patterns were accordant with the enhanced resistance from seedlings to adult plants, and the grain development from panicle formation to fully-filled seeds. Divergence analysis of miR530 precursor with upstream 1,000-bp promoter sequence in 11 rice species revealed that miR530 was diverse in Oryza sativa japonica and O. sativa indica group, which was consistent with the different accumulation of miR530 in japonica accessions and indica accessions. Altogether, our results indicate that miR530 coordinates rice resistance, yield, and maturity, thus providing a potential regulatory module for breeding programs aiming to improve yield and disease resistance.

Penicillium expansum is an important postharvest pathogen of pomaceous fruit and a causal agent of blue mold or soft rot. In this study, we investigated the effect of ambient pH on growth, ultrastructure alteration, and pathogenicity of P. expansum, as well as accumulation of patulin and expression of genes involved in patulin biosynthesis. Under different pH, the fungus was routinely cultured and collected for growth, pathogenicity, patulin production, and gene expression studies using transmission electron microscopy, apple inoculation, HPLC, and RT-qPCR methods. Different ambient pH had significant impact on expression of genes and growth factors involved in patulin biosynthesis. Under same range of pH, gene expression profile, growth factors, and patulin accumulation (in vivo and in vitro) all showed similar changing trends. A well-developed cell was observed in addition to upregulation of genes at pH between pH 5.0 and 7.0, while the opposite was observed when pH was too basic (8.5) or too acid (2.5). Additionally, ambient pH had direct or indirect influence on expression of PecreaA, PelaeA, and PepacC. These findings will help in understanding the effect of ambient pH on growth, pathogenicity, and patulin production and support the development of successful methods for combating P. expansum infection on apple fruits.

Ustilaginoidea virens is a biotrophic fungal pathogen specifically colonizing rice floral organ and causes false smut disease of rice. This disease has emerged as a serious problem that hinders the application of high-yield rice cultivars, by reducing grain yield and quality as well as introducing mycotoxins. However, the pathogenic mechanisms of U. virens are still enigmatic. Here we demonstrate that U. virens employs a secreted protein UvCBP1 to manipulate plant immunity. In planta expression of UvCBP1 led to compromised chitin-induced defense responses in Arabidopsis and rice, including burst of reactive oxygen species (ROS), callose deposition, and expression of defense-related genes. In vitro-purified UvCBP1 protein competes with rice chitin receptor OsCEBiP to bind to free chitin, thus impairing chitin-triggered rice immunity. Moreover, UvCBP1 could significantly promote infection of U. virens in rice flowers. Our results uncover a mechanism of a floral fungus suppressing plant immunity and pinpoint a universal role of chitin-battlefield during plant–fungi interactions.

MicroRNAs (miRNAs) play vital roles in plant development and defense responses against various stresses. Here we show that blocking miR1871 improves rice resistance against Magnaporthe oryzae and enhances grain yield simultaneously. The transgenic lines overexpressing miR1871 (OX1871) exhibit compromised resistance, suppressed defense responses, and reduced panicle number resulting in slightly decreased yield. In contrast, the transgenic lines blocking miR1871 (MIM1871) show improved resistance, enhanced defense responses, and significantly increased panicle number leading to enhanced yield per plant. The RNA-seq assay and defense responses assays reveal that blocking miR1871 resulted in the enhancement of PAMP-triggered immunity (PTI). Intriguingly, miR1871 suppresses the expression of LOC_Os06g22850, which encodes a microfibrillar-associated protein (MFAP1) locating nearby the cell wall and positively regulating PTI responses. The mutants of MFAP1 resemble the phenotype of OX1871. Conversely, the transgenic lines overexpressing MFAP1 (OXMFAP1) or overexpressing both MFAP1 and miR1871 (OXMFAP1/OX1871) resemble the resistance of MIM1871. The time-course experiment data reveal that the expression of miR1871 and MFAP1 in rice leaves, panicles, and basal internode is dynamic during the whole growth period to manipulate the resistance and yield traits. Our results suggest that miR1871 regulates rice yield and immunity via MFAP1, and the miR8171-MFAP1 module could be used in rice breeding to improve both immunity and yield.

Many rice microRNAs have been identified as fine-tuning factors in the regulation of agronomic traits and immunity. Among them, Osa-miR535 targets SQUAMOSA promoter binding protein-like 14 (OsSPL14) to positively regulate tillers but negatively regulate yield and immunity. Here, we uncovered that Osa-miR535 targets another SPL gene, OsSPL4, to suppress rice immunity against Magnaporthe oryzae. Overexpression of Osa-miR535 significantly decreased the accumulation of the fusion protein SPL4

MicroRNAs (miRNAs) play important roles in rice response to Magnaporthe oryzae, the causative agent of rice blast disease. Studying the roles of rice miRNAs is of great significance for the disease control. Osa-miR167d belongs to a conserved miRNA family targeting auxin responsive factor (ARF) genes that act in developmental and stress-induced responses. Here, we show that Osa-miR167d plays a negative role in rice immunity against M. oryzae by suppressing its target gene. The expression of Osa-miR167d was significantly suppressed in a resistant accession at and after 24 h post inoculation (hpi), however, its expression was significantly increased at 24 hpi in the susceptible accession upon M. oryzae infection. Transgenic rice lines over-expressing Osa-miR167d were highly susceptible to multiple blast fungal strains. By contrast, transgenic lines expressing a target mimicry to block Osa-miR167d enhanced resistance to rice blast disease. In addition, knocking out the target gene ARF12 led to hyper-susceptibility to multiple blast fungal strains. Taken together, our results indicate that Osa-miR167d negatively regulate rice immunity to facilitate the infection of M. oryzae by downregulating ARF12. Thus, Osa-miR167d-ARF12 regulatory module could be valuable in improvement of blast-disease resistance.

The anticancer drug 6-MP was covalently bonded to the –OH group of poly(HPMA) via a glutathione-responsive carbonyl vinyl sulfide linker. In vitro simulation assay demonstrated that the poly(HPMA)–PTA conjugate exhibited a markedly enhanced antitumor effect on HepG2 cells.

In this study, we report the preparation and characterization of the PVA–DTPA–Gd conjugate as a potential MRI contrast agent (CA). The r1 value and the r2/r1 ratio were about 5.6 mM−1 s−1 and 1.31, respectively. In vitro toxicity studies not only demonstrated that the polymeric system possessed good biocompatibility, but also proved that the conjugate could be an attractive candidate for CA.