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We study the propagation of a relativistic ultrashort laser pulse in two-dimensional inhomogeneous plasma with a density ripple based on the theoretical analysis and the particle-in-cell simulation. An analytical solution of the laser pulse propagating in the homogeneous plasma is completely obtained. It is found that the stable propagation of the relativistic ultrashort laser pulse in homogeneous plasma can be realized, and the propagation distance and intensity of the laser pulse and the spatial distribution of electron density can be effectively modulated by adjusting the pulsewidth of the incident laser and the plasma frequency. More interestingly, in the inhomogeneous plasma with a density ripple, when the wave amplitude of the density ripple is less than a critical value, the intensity of the ultrashort laser pulse is almost unchanged and the propagation characteristics of the laser in the inhomogeneous plasma are basically consistent with those in the homogeneous plasma. However, when the wave amplitude of the density ripple is larger than the critical value, the inhomogeneity of the plasma has an obvious effect on the laser characteristics, and the intensity and the spatial distribution of the laser pulse will be modulated by the plasma density ripple. The influence of the laser pulsewidth, plasma density, and plasma density ripple on the laser characteristics is discussed in detail. [ABSTRACT FROM AUTHOR]

Background: Chronic cough is a common symptom in children and protracted bacterial bronchitis (PBB) is one of the causes of chronic cough. However, the understanding of this disease remains limited. The present study aims to update PBB in children. Methods: The clinical data of children with PBB from 2014 to 2018 were retrospectively analyzed, and PBB clinical features of published studies were summarized. Electronic databases were searched in May 2019. Clinical studies were included in the present study. Reviews were undertaken in duplicate. Results: Totally 712 cases were analyzed in this study, including 52 cases in our center and 660 cases from 14 studies. In the 52 cases, 88.5% of patients with PBB were less than 6 years old and all of them complained of wet cough. Three cases were confirmed with laryngomalacia, and microbiologically-based-PBB were identified in 13 cases (9 Streptococcus pneumonia, 3 Staphylococcus aureus, and 1 Pseudomonas aeruginosa). Twenty cases were completely remitted after treatment. In the 14 studies, the patients with PBB were typically younger than 3 years old, accompanying wheezing and airway malacia. Co-infection was common in most western cases, Streptococcus pneumonia, Haemophilus influenza and Moraxella catarrhalis were the top three pathogens. Symptoms were improved in most patients, whereas some cases with comorbidities required prolonged antibiotics treatment. Conclusions: PBB is common in male infants with chronic wet cough and accompanied by wheezing and airway deformities. Most cases are clinically diagnosed PBB in China and microbiologically-based-PBB is common in western countries. Co-infection could be found, Streptococcus pneumoniae and Haemophilus influenza were the most frequent etiology in China and western countries, respectively. Patients with comorbidities may need extended antibiotics treatment for more than 2 weeks. [ABSTRACT FROM AUTHOR]

Abstract: We previously reported a spotted‐leaf mutant pelota (originally termed HM47) in rice displaying arrested growth and enhanced resistance to multiple races of Xanthomonas oryzae pv. oryzae. Here, we report the map‐based cloning of the causal gene OsPELOTA (originally termed splHM47). We identified a single base substitution from T to A at position 556 in the coding sequence of OsPELOTA, effectively mutating phenylalanine to isoleucine at position 186 in the translated protein sequence. Both functional complementation and over‐expression could rescue the spotted‐leaf phenotype. OsPELOTA, a paralogue to eukaryotic release factor 1 (eRF1), shows high sequence similarity to Drosophila Pelota and also localizes to the endoplasmic reticulum and plasma membrane. OsPELOTA is constitutively expressed in roots, leaves, sheaths, stems, and panicles. Elevated levels of salicylic acid and decreased level of jasmonate were detected in the pelota mutant. RNA‐seq analysis confirmed that genes responding to salicylic acid were upregulated in the mutant. Our results indicate that the rice PELOTA protein is involved in bacterial leaf blight resistance by activating the salicylic acid metabolic pathway. [ABSTRACT FROM AUTHOR]

To efficiently utilize energy, refrigeration industries, including air conditioning, have put forward higher and higher requirements for the performances of copper pipes used for heat exchangers. Horizontal continuous casting of pipe blank is a key process in production of copper pipes, and optimization of its technological parameters has positive effects on improving the structure uniformity of casting blank. The stability of the performances of pipe blank also directly influences the quality of subsequent machining process. In this paper, numerical analysis was carried out for the temperature field and structure field during solidification of pipe blank in the crystallizer for horizontal continuous casting, and the steady-state sump depth and morphology in the crystallizer for continuous casting, which could be used to evaluate production safety, were obtained. Quantitative analysis was conducted for the laws of influence of different casting technological parameters, such as cooling water flow rate, withdrawal speed, and casting temperature, on the sump morphology in the crystallizer for casting blank and the final distribution of structure field in casting blank. Metallographic experiment was carried out for casting blank, and the results were compared visually with the structure field from simulation calculation, to provide measurable reference bases for further optimizing the horizontal casting technological parameters for copper pipes. [ABSTRACT FROM AUTHOR]

This paper introduces the canonical coordinates method to obtain the first integral of a single-degree freedom constraint mechanical system that contains conservative and non-conservative constraint homonomic systems. The definition and properties of canonical coordinates are introduced. The relation between Lie point symmetries and the canonical coordinates of the constraint mechanical system are expressed. By this relation, the canonical coordinates can be obtained. Properties of the canonical coordinates and the Lie symmetry theory are used to seek the first integrals of constraint mechanical system. Three examples are used to show applications of the results. [ABSTRACT FROM AUTHOR]

Our study investigates the genetic mechanisms underlying the spotted leaf phenotype in rice, focusing on the spl43 mutant. This mutant is characterized by persistent reddish-brown leaf spots from the seedling stage to maturity, leading to extensive leaf necrosis. Using map-based cloning, we localized the responsible locus to a 330 Kb region on chromosome 2. We identified LOC_Os02g56000, named OsRPT5A, as the causative gene. A point mutation in OsRPT5A, substituting valine for glutamic acid, was identified as the critical factor for the phenotype. Functional complementation and the generation of CRISPR/Cas9-mediated knockout lines in the IR64 background confirmed the central role of OsRPT5A in controlling this trait. The qPCR results from different parts of the rice plant revealed that OsRPT5A is constitutively expressed across various tissues, with its subcellular localization unaffected by the mutation. Notably, we observed an abnormal accumulation of reactive oxygen species (ROS) in spl43 mutants by examining the physiological indexes of leaves, suggesting a disruption in the ROS system. Complementation studies indicated OsRPT5A's involvement in ROS homeostasis and catalase activity regulation. Moreover, the spl43 mutant exhibited enhanced resistance to Xanthomonas oryzae pv. oryzae (Xoo), highlighting OsRPT5A's role in rice pathogen resistance mechanisms. Overall, our results suggest that OsRPT5A plays a critical role in regulating ROS homeostasis and enhancing pathogen resistance in rice. [ABSTRACT FROM AUTHOR]

In order to find out the relationship between flotation process and energy input, the flotation tests were optimized by increasing input power in the flotation process. The drive motor speeds were 1 500, 1 800, 2 100, 2 400 and 2 700 r/min at different flotation periods. The flotation process was separated into five flotation periods of 0.5, 0.5, 1.0, 1.0, 2.0 min. The power dissipation in the flotation process was measured by energy measurement system. The flotation results show that the flotation rate, combustible matter recovery and accumulated ash content of clean coal increases with the increasing of rotate speed in the primary stage of flotation process. The combustible matter recovery is low while the quality of clean coal is high in the case of low energy input. The accumulated ash content of clean coal is the lowest and combustible matter recovery is higher while the drive motor speeds are 1 500, 1 500, 1 500, 1 500 and 2 400 r/min at the five flotation periods, respectively. The clean coal with higher combustible matter recovery and quality can be obtained while energy input is lower at the early stage of flotation process and higher at the later stage of flotation process in the case of same or similar total energy input. [ABSTRACT FROM AUTHOR]

Polymorphisms have been identified to predispose to primary gouty arthritis (GA) and hyperuricemia (HUA). Here, we accessed the five polymorphisms of rs10754558, rs35829419, rs3738448, rs3806268, and rs7525979 in NLRP3 on GA and HUA susceptibility. We collected 1198 samples (314 GA, 377 HUA, and 507 controls) for this case-control study. Our data detected that the rs3806268 (GA vs. AA: OR = 0.65 , p = 0.012) was significantly associated with the susceptibility to GA. The rs3738448 (TT vs. GG: OR = 2.05 , p = 0.024) and rs7525979 (TT vs. CC: OR = 1.96 , p = 0.037) were significantly associated with the susceptibility to HUA. The rs3806268 AG genotype presented decreased risk of GA among the hypertension (OR = 0.54 , p = 0.0093), smoking (OR = 0.59 , p = 0.018), and no obesity (OR = 0.60 , p = 0.0097) subjects compared to the GG genotype group. The rs3738448 TT genotype demonstrated increased risk of HUA among the hypertension (OR = 4.10 , p = 0.0056) and no drinking population (OR = 3.56 , p = 0.016) compared to the GG genotype group. The rs7525979 TT genotype demonstrated increased risk of HUA among the hypertension (OR = 4.01 , p = 0.0064) and no drinking population (OR = 3.24 , p = 0.034) compared to the CC genotype group. Furthermore, a significant haplotype effect of rs10754558/C-rs35829419/C-rs3738448/G-rs3806268/A-rs7525979/C was found (OR = 1.60 , p = 0.0046) compared with GCGAC haplotype. Bioinformatics analyses indicated that rs3738448, rs3806268, and rs7525979 might influence the gene regulation, while the T-allele of rs3738448 increased the stability of NLRP3-mRNA. Collectively, our case-control study confirms NLRP3 polymorphisms might participate in regulating immune and inflammation responses in GA and HUA. [ABSTRACT FROM AUTHOR]

Applying machine learning technology to automatic image analysis and auxiliary diagnosis of whole slide image (WSI) may help to improve the efficiency, objectivity, and consistency of pathological diagnosis. Due to its extremely high resolution, it is still a great challenge to directly process WSI through deep neural networks. In this paper, we propose a novel model for the task of classification of WSIs. The model is composed of two parts. The first part is a self-supervised encoding network with a UNet-like architecture. Each patch from a WSI is encoded as a compressed latent representation. These features are placed according to their corresponding patch's original location in WSI, forming a feature cube. The second part is a classification network fused by 4 famous network blocks with heterogeneous architectures, with feature cube as input. Our model effectively expresses the feature and preserves location information of each patch. The fused network integrates heterogeneous features generated by different networks which yields robust classification results. The model is evaluated on two public datasets with comparison to baseline models. The evaluation results show the effectiveness of the proposed model. [ABSTRACT FROM AUTHOR]

Copper tubes are efficient heat exchange parts in refrigeration industry, and their quality has a bearing on the grade of corresponding products. The cooling process of copper tube after three-roll planetary rolling is a key step in the production of copper tube by the casting and rolling method, and its cooling effect matters to the quality of copper tube products. Aiming at the characteristics of motion of a rolled piece in the through water cooling with a cooling water jacket, the method of "stepwise" moving cooling water jacket was used in this paper to achieve equivalence to the motion of the rolled piece, realizing finite element simulation of the whole process of three-roll planetary rolling and cooling of copper tube. The velocity field and pressure field of the fluid in the cooling water model were analyzed, and it was found that there existed a flow "dead zone" with the velocity below 8 m/s, there was a "negative pressure" phenomenon, and there were more eddy currents occurring. Through the study on the temperature field during the cooling process of the rolled piece, it was found that there was a phenomenon of non-uniform temperature distribution in the cooling process of the rolled piece. With the maximum temperature difference at each monitoring point in the cooling process of rolled piece as the evaluation criterion for the uniformity of temperature distribution in the cooling process of rolled piece, the process parameters affecting the rolled piece cooling effect, including the size of water inlet, the size of water outlet, and the pressure of entering water, were studied respectively, and the optimum process parameter values for improving the quality of rolled pieces were finally obtained. The accuracy of the model was verified by comparatively analyzing the metallographic microstructure and microhardness between the factory produced sample and the thermally simulated sample. • Realize the whole process of three-roll planetary rolling and cooling of the tube. • Simulation method of "stepwise" moving cooling water jacket was used. • It was found that there existed a flow "dead zone". • There were "negative pressure" phenomenon and eddy current phenomena occurring. [ABSTRACT FROM AUTHOR]

The effects of super-Gaussian chirped laser pulse and inhomogeneity of plasma on space distribution and amplitude of wakefield are studied. The different super-Gaussian chirped laser pulse envelopes are used to strike the uniform and various inhomogeneous plasmas. The results show that compared with the unchirped laser pulse, the chirped laser pulse can enhance the wakefield generation, make the bubbles’ structure deformative seriously, reduce the numbers of bubbles in the same longitudinal distance, and enlarge the size of the wakefield bubbles. Besides, the stronger wakefield is generated in inhomogeneous plasma compared with a uniform one. Moreover, the characteristics of the wakefield can be controlled efficiently by the super-Gaussian pulse index. That is, the amplitude and spatial structure of the plasma wakefield can be modulated by the super-Gaussian chirped laser pulse and the inhomogeneity of the plasma. [ABSTRACT FROM AUTHOR]

A premature senescence and death 128 ( psd128) mutant was isolated from an ethyl methane sulfonate-induced rice IR64 mutant bank. The premature senescence phenotype appeared at the six-leaf stage and the plant died at the early heading stage. psd128 exhibited impaired chloroplast development with significantly reduced photosynthetic ability, chlorophyll and carotenoid contents, root vigor, soluble protein content and increased malonaldehyde content. Furthermore, the expression of senescence-related genes was significantly altered in psd128. The mutant trait was controlled by a single recessive nuclear gene. Using map-based strategy, the mutation Oryza sativa cell division cycle 48 ( OsCDC48) was isolated and predicted to encode a putative AAA-type ATPase with 809 amino-acid residuals. A single base substitution at position C2347T in psd128 resulted in a premature stop codon. Functional complementation could rescue the mutant phenotype. In addition, RNA interference resulted in the premature senescence and death phenotype. OsCDC48 was expressed constitutively in the root, stem, leaf and panicle. Subcellular analysis indicated that OsCDC48:YFP fusion proteins were located both in the cytoplasm and nucleus. OsCDC48 was highly conserved with more than 90% identity in the protein levels among plant species. Our results indicated that the impaired function of OsCDC48 was responsible for the premature senescence and death phenotype. [ABSTRACT FROM AUTHOR]

Background. Osteoporotic vertebral compression fractures (OVCFs) are common health issues in the elderly that cause chronic pain in over one-third of patients. This study was sought to evaluate the efficacy and safety of acupuncture for alleviating pain caused by OVCFs. Methods. We performed a search of 8 electronic databases for publications from the inception to 30th March 2021. Eligible studies were randomized clinical trials (RCTs) that evaluated the effect of acupuncture for the treatment of OVCFs. Two investigators evaluated literature quality and extracted data independently. RevMan V.5.4.1 was used for data analyses, with pooled risk estimates presented as mean difference (MD) or relative risk (RR) along with corresponding 95% confidence intervals (CIs), as appropriate. Results. Fourteen RCTs involving 1,130 patients were included in this meta-analysis. Compared with the control group, acupuncture showed a greater benefit on pain reduction caused by OVCFs (1 week: MD = −1.26, 95% CI: (−1.82,−0.70); 1 month: MD = −1.63, 95% CI: (−1.82,−1.43); 6 months: MD = −1.13, 95% CI: (−1.55, −0.70)). Acupuncture treatment was also associated with fewer adverse events, lower ODI index, and higher bone density than the control group (safety: (RR: 0.30, 95% CI: 0.12–0.75); ODI: MD = −3.19, 95% CI: (−5.20, −1.19); bone density: MD = 0.15, 95% CI: (0.05, 0.26)). The GRADE quality of these results was assessed as low or very low. Conclusions. Compared with the control treatment, acupuncture was more effective and safer in relieving the pain caused by OVCF and made a greater improvement on patient's ODI score and bone density. Given the low level of our study evidence, future high-quality studies are needed to verify our study findings. [ABSTRACT FROM AUTHOR]

The spindle and kinetochore-associated protein complex (Ska) is an essential component in chromosome segregation. It comprises three proteins (Ska1, Ska2, and Ska3) with theorized roles in chromosomal instability and tumor development, and its overexpression has been widely reported in a variety of tumors. However, the prognostic significance and immune infiltration of Ska proteins in hepatocellular carcinoma (HCC) are not completely understood. The bioinformatics tools Oncomine, UALCAN, gene expression profiling interactive analysis 2 (GEPIA2), cBioPortal, GeneMANIA, Metascape, and TIMER were used to analyze differential expression, prognostic value, genetic alteration, and immune cell infiltration of the Ska protein complex in HCC patients. We found that the mRNA expression of the Ska complex was markedly upregulated in HCC. High expression of the Ska complex is closely correlated with tumor stage, patient race, tumor grade, and TP53 mutation status. In addition, high expression of the Ska complex was significantly correlated with poor disease-free survival, while the high expression levels of Ska1 and Ska3 were associated with shorter overall survival. The biological functions of the Ska complex in HCC primarily involve the amplification of signals from kinetochores, the mitotic spindle, and (via a MAD2 invasive signal) unattached kinetochores. Furthermore, the expression of the complex was positively correlated with tumor-infiltrating cells. These results may provide new insights into the development of immunotherapeutic targets and prognostic biomarkers for HCC. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a chronic degenerative disease of the bone and joints. Immune-related genes and immune cell infiltration are important in OA development. We analyzed immune-related genes and immune infiltrates to identify OA diagnostic markers. The datasets GSE51588, GSE55235, GSE55457, GSE82107, and GSE114007 were downloaded from the Gene Expression Omnibus database. First, R software was used to identify differentially expressed genes (DEGs) and differentially expressed immune-related genes (DEIRGs), and functional correlation analysis was conducted. Second, CIBERSORT was used to evaluate infiltration of immune cells in OA tissue. Finally, the least absolute shrinkage and selection operator logistic regression algorithm and support vector machine-recurrent feature elimination algorithm were used to screen and verify diagnostic markers of OA. A total of 711 DEGs and 270 DEIRGs were identified in this study. Functional enrichment analysis showed that the DEGs and DEIRGs are closely related to cellular calcium ion homeostasis, ion channel complexes, chemokine signaling pathways, and JAK-STAT signaling pathways. Differential analysis of immune cell infiltration showed that M1 macrophage infiltration was increased but that mast cell and neutrophil infiltration were decreased in OA samples. The machine learning algorithm cross-identified 15 biomarkers (BTC, PSMD8, TLR3, IL7, APOD, CIITA, IFIH1, CDC42, FGF9, TNFAIP3, CX3CR1, ERAP2, SEMA3D, MPO, and plasma cells). According to pass validation, all 15 biomarkers had high diagnostic efficacy (AUC > 0.7), and the diagnostic efficiency was higher when the 15 biomarkers were fitted into one variable (AUC = 0.758). We developed 15 biomarkers for OA diagnosis. The findings provide a new understanding of the molecular mechanism of OA from the perspective of immunology. [ABSTRACT FROM AUTHOR]

A rice chlorophyll-deficient mutant w67 was isolated from an ethyl methane sulfonate (EMS)–induced IR64 (Oryza sativa L. ssp. indica) mutant bank. The mutant exhibited a distinct yellow-green leaf phenotype in the whole plant growth duration with significantly reduced levels of chlorophyll and carotenoid, impaired chloroplast development and lowered capacity of photosynthesis compared with the wild-type IR64. Expression of a number of genes associated with chlorophyll metabolism, chloroplast biogenesis and photosynthesis was significantly altered in the mutant. Genetic analysis indicated that the yellow-green phenotype was controlled by a single recessive nuclear gene located on the short arm of chromosome 3. Using map-based strategy, the mutation was isolated and predicted to encode a chloroplast signal recognition particle 43 KD protein (cpSRP43) with 388 amino acid residuals. A single base substitution from A to T at position 160 resulted in a premature stop codon. OscpSRP43 was constitutively expressed in various organs with the highest level in the leaf. Functional complementation could rescue the mutant phenotype and subcellular localization showed that the cpSRP43:GFP fusion protein was targeted to the chloroplast. The data suggested that Oryza sativa cpSRP43 (OscpSRP43) was required for the normal development of chloroplasts and photosynthesis in rice. [ABSTRACT FROM AUTHOR]

Background: Spotted leaf mutants show typical necrotic lesions that appear spontaneously in the absence of any pathogen attack. These mutants are often characterized to exhibit programmed cell death (PCD) and activation of plant defense responses resulting in enhanced disease resistance to multiple pathogens. Here, we reported a novel spotted-leaf mutant, spl40 that showed enhanced disease resistance response. Results: Initially lesions appeared at leaf tips during seedling stage and gradually covered the whole leaf at the tillering stage. The lesion development was light-dependent. spl40 showed obvious cell death at and around the lesion, and burst of reactive oxygen species (ROS) was accompanied by disturbed ROS scavenging system. Photosynthetic capacity was compromised as evidenced by significant reductions in chlorophyll content, important photosynthesis parameters and downregulated expression of photosynthesis-related genes which ultimately led to poor performance of major agronomic traits. spl40 exhibited enhanced resistance to 14 out of 16 races of bacterial blight pathogen of rice, caused by Xanthomonas oryzae pv. oryzae, most probably though activation of SA and JA signaling pathways, owing to upregulated expression of SA and JA signaling genes, though the exact mechanism remain to be elucidated. The spotted-leaf phenotype was controlled by a novel single recessive nuclear gene. Genetic mapping combined with high throughput sequencing analysis identified Os05G0312000 as the most probable candidate gene. Sequencing of ORF revealed a single SNP change from C to T that resulted in non-synonymous change in amino acid residue from leucine to phenylalanine. Interestingly, the complementation plants did not display lesions before heading but showed lesions at the heading stage and the transgenic T1 progenies could be classified into 3 categories based on their lesion intensity, indicating the complex genetic nature of the spl40 mutation. Conclusion: The results obtained here clearly show that genes related to defense and PCD were upregulated in accordance with enhanced disease resistance and occurrence of PCD, whereas the photosynthetic capacity and overall ROS homeostasis was compromised in spl40. Our data suggest that a novel spotted-leaf mutant, spl40, would help to elucidate the mechanism behind lesion development involving programmed cell death and associated defense responses. [ABSTRACT FROM AUTHOR]

Many spotted-leaf mutants show enhanced disease resistance to multiple pathogen attacks; however, the mechanisms are largely unknown. Here, we reported a novel semi-dominant spotted-leaf mutant 24 (spl24) obtained from an ethyl methane sulfonate (EMS)-induced IR64 mutant bank. spl24 developed tiny brown lesions on the leaf tip and spread down gradually to the leaf base as well as the sheath at the early heading stage. The performances of major agronomic traits such as the plant height, panicle length, number of panicles/plant, and 1000-grain weight were significantly altered in spl24 when compared to the wild-type IR64. Furthermore, spl24 exhibited a premature senescing phenotype with degeneration of nuclear acids, significantly reduced soluble protein content, increased level of malonaldehyde (MDA), and lowered activities of reactive oxygen species (ROS) scavenging enzymes. Disease evaluation indicated that spl24 showed enhanced resistance to multiple races of Xanthomonas oryzae pv. oryzae, the causal pathogen of bacterial leaf blight in rice, with elevated expression of pathogenesis-related genes, salicylic acid (SA) signaling pathway-associated genes revealed by real-time quantitative PCR and high-throughput RNA sequencing analysis. Genetic analysis and gene mapping indicated that the lesion mimic phenotype was controlled by a novel semi-dominant nuclear gene. The mutation, tentatively termed as OsSPL24, was in a 110 kb region flanked by markers Indel-33 and Indel-12 in chromosome 11. Together, our data suggest that spl24 is a novel lesion mimic mutant with enhanced innate immunity and would facilitate the isolation and functional characterization of the target gene. [ABSTRACT FROM AUTHOR]

Background: Spotted-leaf mutants are important to reveal programmed cell death and defense-related pathways in rice. We previously characterized the phenotype performance of a rice spotted-leaf mutant spl21 and narrowed down the causal gene locus spl21(t) to an 87-kb region in chromosome 12 by map-based cloning. Result: We showed that a single base substitution from A to G at position 836 in the coding sequence of Oryza sativa beta-1,6-N-acetylglucosaminyl transferase (OsGCNT), effectively mutating Tyr to Cys at position 279 in the translated protein sequence, was responsible for the spotted-leaf phenotype as it could be rescued by functional complementation. Compared to the wild type IR64, the spotted-leaf mutant spl21 exhibited loss of chlorophyll, breakdown of chloroplasts, down-regulation of photosynthesis-related genes, and up-regulation of senescence associated genes, which indicated that OsGCNT regulates premature leaf senescence. Moreover, the enhanced resistance to the bacterial leaf blight pathogen Xanthomonas oryzae pv. oryzae, up-regulation of pathogenesis-related genes and increased level of jasmonate which suggested that OsGCNT is a negative regulator of defense response in rice. OsGCNT was expressed constitutively in the leaves, sheaths, stems, roots, and panicles, and OsGCNT-GFP was localized to the Golgi apparatus. High throughput RNA sequencing analysis provided further evidence for the biological effects of loss of OsGCNT function on cell death, premature leaf senescence and enhanced disease resistance in rice. Thus, we demonstrated that the novel OsGCNT regulated rice innate immunity and immunity-associated leaf senescence probably by changing the jasmonate metabolic pathway. Conclusions: These results reveal that a novel gene Oryza sativa beta-1,6-N-acetylglucosaminyl transferase (OsGCNT) is responsible for the spotted-leaf mutant spl21, and OsGCNT acts as a negative-regulator mediating defense response and immunity-associated premature leaf senescence probably by activating jasmonate signaling pathway. [ABSTRACT FROM AUTHOR]