PABP/purine-rich motif as an initiation module for cap-independent translation in pattern-triggered immunity.

Upon stress, eukaryotes typically reprogram their translatome through GCN2-mediated phosphorylation of the eukaryotic translation initiation factor, eIF2α, to inhibit general translation initiation while selectively translating essential stress regulators. Unexpectedly, in plants, pattern-triggered immunity (PTI) and response to other environmental stresses occur independently of the GCN2/eIF2α pathway. Here, we show that while PTI induces mRNA decapping to inhibit general translation, defense mRNAs with a purine-rich element ("R-motif") are selectively translated using R-motif as an internal ribosome entry site (IRES). R-motif-dependent translation is executed by poly(A)-binding proteins (PABPs) through preferential association with the PTI-activating eIFiso4G over the repressive eIF4G. Phosphorylation by PTI regulators mitogen-activated protein kinase 3 and 6 (MPK3/6) inhibits eIF4G's activity while enhancing PABP binding to the R-motif and promoting eIFiso4G-mediated defense mRNA translation, establishing a link between PTI signaling and protein synthesis. Given its prevalence in both plants and animals, the PABP/R-motif translation initiation module may have a broader role in reprogramming the stress translatome.

The H1/H5 domain contributes to OsTRBF2 phase separation and gene repression during rice development.

Transcription factors (TFs) tightly control plant development by regulating gene expression. The phase separation of TFs plays a vital role in gene regulation. Many plant TFs have the potential to form phase-separated protein condensates; however, little is known about which TFs are regulated by phase separation and how it affects their roles in plant development. Here, we report that the rice (Oryza sativa) single Myb TF TELOMERE REPEAT-BINDING FACTOR 2 (TRBF2) is highly expressed in fast-growing tissues at the seedling stage. TRBF2 is a transcriptional repressor that binds to the transcriptional start site of thousands of genes. Mutation of TRBF2 leads to pleiotropic developmental defects and misexpression of many genes. TRBF2 displays characteristics consistent with phase separation in vivo and forms phase-separated condensates in vitro. The H1/H5 domain of TRBF2 plays a crucial role in phase separation, chromatin targeting, and gene repression. Replacing the H1/H5 domain by a phase-separated intrinsically disordered region from Arabidopsis (Arabidopsis thaliana) AtSERRATE partially recovers the function of TRBF2 in gene repression in vitro and in transgenic plants. We also found that TRBF2 is required for trimethylation of histone H3 Lys27 (H3K27me3) deposition at specific genes and genome wide. Our findings reveal that phase separation of TRBF2 facilitates gene repression in rice development.

m6A modification plays an integral role in mRNA stability and translation during pattern-triggered immunity.

Plants employ distinct mechanisms to respond to environmental changes. Modification of mRNA by N 6-methyladenosine (m6A), known to affect the fate of mRNA, may be one such mechanism to reprogram mRNA processing and translatability upon stress. However, it is difficult to distinguish a direct role from a pleiotropic effect for this modification due to its prevalence in RNA. Through characterization of the transient knockdown-mutants of m6A writer components and mutants of specific m6A readers, we demonstrate the essential role that m6A plays in basal resistance and pattern-triggered immunity (PTI). A global m6A profiling of mock and PTI-induced Arabidopsis plants as well as formaldehyde fixation and cross-linking immunoprecipitation-sequencing of the m6A reader, EVOLUTIONARILY CONSERVED C-TERMINAL REGION2 (ECT2) showed that while dynamic changes in m6A modification and binding by ECT2 were detected upon PTI induction, most of the m6A sites and their association with ECT2 remained static. Interestingly, RNA degradation assay identified a dual role of m6A in stabilizing the overall transcriptome while facilitating rapid turnover of immune-induced mRNAs during PTI. Moreover, polysome profiling showed that m6A enhances immune-associated translation by binding to the ECT2/3/4 readers. We propose that m6A plays a positive role in plant immunity by destabilizing defense mRNAs while enhancing their translation efficiency to create a transient surge in the production of defense proteins.

The influencing factors of hearing protection device usage among noise-exposed workers in Guangdong Province: a structural equation modeling-based survey.

BACKGROUND: There are numerous complex barriers and facilitators to continuously wearing hearing protection devices (HPDs) for noise-exposed workers. Therefore, the present study aimed to investigate the relationship between HPD wearing behavior and hearing protection knowledge and attitude, HPD wearing comfort, and work-related factors. METHOD: A cross-sectional study was conducted with 524 noise-exposed workers in manufacturing enterprises in Guangdong Province, China. Data were collected on hearing protection knowledge and attitudes, HPD wearing comfort and behavior, and work-related factors through a questionnaire. Using structural equation modeling (SEM), we tested the association among the study variables. RESULTS: Among the total workers, 69.47% wore HPD continuously, and the attitudes of hearing protection (26.17 ± 2.958) and total HPD wearing comfort (60.13 ± 8.924) were satisfactory, while hearing protection knowledge (3.54 ± 1.552) was not enough. SEM revealed that hearing protection knowledge had direct effects on attitudes (ß = 0.333, p < 0.01) and HPD wearing behavior (ß = 0.239, p < 0.01), and the direct effect of total HPD wearing comfort on behavior was ß = 0.157 (p < 0.01). The direct effect also existed between work shifts and behavior (ß=-0.107, p < 0.05). Indirect relationships mainly existed between other work-related factors, hearing protection attitudes, and HPD wearing behavior through knowledge. Meanwhile, work operation had a direct and negative effect on attitudes (ß=-0.146, p < 0.05), and it can also indirectly and positively affect attitudes through knowledge (ß = 0.08, p < 0.05). CONCLUSION: The behavior of wearing HPD was influenced by hearing protection knowledge, comfort in wearing HPD, and work-related factors. The results showed that to improve the compliance of noise-exposed workers wearing HPD continuously when exposed to noise, the HPD wearing comfort and work-related factors must be taken into consideration. In addition, we evaluated HPD wearing comfort in physical and functional dimensions, and this study initially verified the availability of the questionnaire scale of HPD wearing comfort.

Integrating CRISPR-Cas12a into a Microfluidic Dual-Droplet Device Enables Simultaneous Detection of HPV16 and HPV18.

Fast, simplified, and multiplexed detection of human papillomaviruses (HPVs) is of great importance for both clinical management and population screening. However, current HPV detection methods often require sophisticated instruments and laborious procedures to detect multiple targets. In this work, we developed a simple microfluidic dual-droplet device (M-D3) for the simultaneous detection of HPV16 and HPV18 by combining the CRISPR-Cas12a system and multiplexed recombinase polymerase amplification (RPA) assay. A new approach of combining pressure/vacuum was proposed for efficient droplet generation with minimal sample consumption. Two groups of droplets that separately encapsulate the relevant Cas12a/crRNA and the fluorescent green or red reporters are parallelly generated, followed by automatic imaging to discriminate the HPV subtypes based on the specific fluorescence of the droplets. The M-D3 platform performs with high sensitivity (∼0.02 nM for unamplified plasmids) and specificity in detecting HPV16 and HPV18 DNA. By combining the RPA and Cas12a assay, M-D3 allows on-chip detection of HPV16 and HPV18 DNA simultaneously within 30 min, reaching a detection limit of 10-18 M (∼1 copy/reaction). Moreover, the outstanding performance of M-D3 was validated in testing 20 clinical patient samples with HPV infection risk, showing a sensitivity of 92.3% and a specificity of 100%. By integrating the dual-droplet generator, CRISPR-Cas12a, and multiplexed RPA, the M-D3 platform provides an efficient way to discriminate the two most harmful HPV subtypes and holds great potential in the applications of multiplexed nucleic acid testing.

Global translational reprogramming is a fundamental layer of immune regulation in plants.

In the absence of specialized immune cells, the need for plants to reprogram transcription to transition from growth-related activities to defence is well understood. However, little is known about translational changes that occur during immune induction. Using ribosome footprinting, here we perform global translatome profiling on Arabidopsis exposed to the microbe-associated molecular pattern elf18. We find that during this pattern-triggered immunity, translation is tightly regulated and poorly correlated with transcription. Identification of genes with altered translational efficiency leads to the discovery of novel regulators of this immune response. Further investigation of these genes shows that messenger RNA sequence features are major determinants of the observed translational efficiency changes. In the 5' leader sequences of transcripts with increased translational efficiency, we find a highly enriched messenger RNA consensus sequence, R-motif, consisting of mostly purines. We show that R-motif regulates translation in response to pattern-triggered immunity induction through interaction with poly(A)-binding proteins. Therefore, this study provides not only strong evidence, but also a molecular mechanism, for global translational reprogramming during pattern-triggered immunity in plants.

uORF-mediated translation allows engineered plant disease resistance without fitness costs.

Controlling plant disease has been a struggle for humankind since the advent of agriculture. Studies of plant immune mechanisms have led to strategies of engineering resistant crops through ectopic transcription of plants' own defence genes, such as the master immune regulatory gene NPR1 (ref. 1). However, enhanced resistance obtained through such strategies is often associated with substantial penalties to fitness, making the resulting products undesirable for agricultural applications. To remedy this problem, we sought more stringent mechanisms of expressing defence proteins. On the basis of our latest finding that translation of key immune regulators, such as TBF1 (ref. 3), is rapidly and transiently induced upon pathogen challenge (see accompanying paper), we developed a 'TBF1-cassette' consisting of not only the immune-inducible promoter but also two pathogen-responsive upstream open reading frames (uORFsTBF1) of the TBF1 gene. Here we demonstrate that inclusion of uORFsTBF1-mediated translational control over the production of snc1-1 (an autoactivated immune receptor) in Arabidopsis thaliana and AtNPR1 in rice enables us to engineer broad-spectrum disease resistance without compromising plant fitness in the laboratory or in the field. This broadly applicable strategy may lead to decreased pesticide use and reduce the selective pressure for resistant pathogens.

STAT3 and SPI1, may lead to the immune system dysregulation and heterotopic ossification in ankylosing spondylitis.

OBJECTIVE: This study was aimed to identify the biomarkers for diagnosis and reveal the immune microenvironment changes in ankylosing spondylitis (AS). METHODS: GSE73754 was downloaded for the co-expression network construction and immune cell analyses. Flow cytometric analysis was performed to validate the results of bioinformatics analysis. Gene set enrichment analysis (GSEA) was performed to investigate the potential biological characteristic between different phenotypes. Pearson correlation analysis between the hub genes and the xCell score of immune cell types was performed. RESULTS: Signal transducer and activator of transcription 3 (STAT3) and Spi-1 proto-oncogene (SPI1) was identified as the hub genes in the datasets GSE73754. And the t-test showed that the expression level of STAT3 and SPI1 in the GSE73754 was significantly higher in AS and human leukocyte antigen (HLA)-B27(+) groups. Flow cytometric analysis showed that natural killer T cells (NKT) cells were upregulated, while Th1 cells were down-regulated in AS, which was consistent with the results obtained from bioinformatics analysis. STAT3 and SPI1 was correlated with the NKT cells and Th1 cells. CONCLUSION: STAT3 and SPI1 may be a key cytokine receptor in disease progression in AS.

Visible-light-promoted nitrone synthesis from nitrosoarenes under catalyst- and additive-free conditions.

A green and sustainable nitrone formation reaction via visible-light-promoted reaction of aryl diazoacetates with nitrosoarenes is described. This protocol exhibits good functional group tolerance and broad substrate scope for both aryl diazoacetates with nitrosoarenes. Comparing the reported methods for the synthesis of nitrones from nitrosoarenes, the reaction described herein occurs under sole visible-light irradiation without the need of any catalysts and additives.

A Retrospective Study of Factors Associated with Restoration of Thoracic Kyphosis in 43 Patients with Adolescent Idiopathic Scoliosis with Lenke Type 1 Curvature.

BACKGROUND This retrospective study aimed to identify the factors associated with successful surgical correction of thoracic kyphosis (TK) in 43 patients with adolescent idiopathic scoliosis (AIS) with Lenke type 1 curvature, in which the major curve with the largest Cobb angle was mainly in the thoracic region. MATERIAL AND METHODS We collected data from patients with Lenke 1 AIS. The following parameters were measured: Cobb angle, side-bending Cobb angle, cervical lordosis (CL), TK, lumbar lordosis (LL), pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT), the sagittal vertical axis (SVA), the center of a C7 plumb line to the center sacral vertical line (C7-CSVL), correction rate, Ponte osteotomy, flexibility, and screw density. Univariate analysis and multivariate logistic regression analyses were performed. RESULTS Among the 43 cases analyzed, the mean postoperative Cobb angle at the last follow-up, C7-CSVL, SVA, CL, TK, LL, PI, SS, and PT were respectively 21.33±9.47°, 10.41±8.45 mm, 19.68±14.33 mm, 16.19±7.45°, 23.12±7.45°, 50.33±11.37°, 49.70±9.83°, 39.42±8.11°, and 10.16±6.63°. Univariate analysis suggested that preoperative TK, preoperative LL, and Ponte osteotomy were statistically significant (P<0.05), and multivariate analysis suggested that preoperative LL and Ponte osteotomy were statistically significant (P<0.05). CONCLUSIONS The results of this study demonstrated that preoperative TK, preoperative LL, and Ponte osteotomy were related factors for maintaining normal TK. Multivariate analysis suggested that preoperative LL and the use of Ponte osteotomy with full-thickness segmental resection of the spinal posterior column resulted in the successful surgical correction of TK in patients with AIS with Lenke type 1 curvature.

Is there a correlation between upper lumbar disc herniation and multifidus muscle degeneration? A retrospective study of MRI morphology.

BACKGROUND: The purpose of the study is to investigate the correlation between upper lumbar disc herniation (ULDH) and multifidus muscle degeneration via the comparison of width, the cross-sectional area and degree of fatty infiltration of the lumbar multifidus muscle. METHODS: Using the axial T2-weighted images of magnetic resonance imaging as an assessment tool, we retrospectively investigated 132 patients with ULDH and 132 healthy individuals. The total muscle cross-sectional area (TMCSA) and the pure muscle cross-sectional area (PMCSA) of the multifidus muscle at the L1/2, L2/3, and L3/4 intervertebral disc levels were measured respectively, and in the meantime, the average multifidus muscle width (AMMW) and degree of fatty infiltration of bilateral multifidus muscle were evaluated. The resulting data were analyzed to determine the presence/absence of statistical significance between the study and control groups. Multivariate logistical regression analyses were used to evaluate the correlation between ULDH and multifidus degeneration. RESULTS: The results of the analysis of the two groups showed that there were statistically significant differences (p < 0.05) between TMCSA, PMCSA, AMMW and degree of fatty infiltration. The multivariate logistic regression analysis indicated that the TMCSA, PMCSA, AMMW and the degree of fatty infiltration of multifidus muscle were correlated with ULDH, and the differences were statistically significant (P < 0.05). CONCLUSIONS: A correlation could exist between multifidus muscles degeneration and ULDH, that may be a process of mutual influence and interaction. Lumbar muscle strengthening training could prevent and improve muscle atrophy and degeneration.

Amino-Supported Palladium Catalyst for Chemo- and Stereoselective Domino Reactions.

A solid amino-supported palladium catalyst is used in an oxidative domino reaction for the diastereoselective construction of alkyne-substituted cyclopentenol compounds. This heterogeneous catalyst exhibits high efficiency and excellent chemoselectivity, as well as good recyclability. The chemoselectivity of the domino reactions was readily controlled by switching the solvent and catalyst. Asymmetric syntheses and an oxidative carbocyclization-borylation reaction have also been developed based on the heterogeneous palladium catalyst.

Enhancing Chain Initiation Efficiency in the Cationic Allyl-Nickel Catalyzed (Co)Polymerization of Ethylene and Methyl Acrylate.

Improving the efficiency of chain initiation is highly important and also highly challenging in the development of olefin polymerization catalysts. A series of 2-methylallyl-based nickel complexes supported by aryl-N-bridged diphosphazane monoxide (PNPO) ligands containing different electronic and steric substituents were prepared and characterized. These nickel complexes are highly active single-component catalysts for ethylene polymerization and copolymerization with methyl acrylate (MA). 2-Methylallyl substituent on the µ-allyl catalysts led to an increase in the efficiency of chain initiation compared with the corresponding allyl-based analogues, improving the catalytic performances with high activity (up to 4.02 × 106 g PE (mol Ni)-1 h-1). Linear polyethylenes with high molecular weight, narrow PDI values, and high melting temperatures were generated. Most importantly, these 2-methylallyl nickel catalysts can promote ethylene-MA copolymerization to afford functionalized polyethylenes with MA incorporation of up to 7.0 mol %. The current work demonstrates that the change of initiating units can lead to enhancement in catalyst performances. This provides an alternative, simple, and potentially general strategy to improve the properties of different catalyst systems.

A Mechanism Underlying Sex-Associated Differences in Ankylosing Spondylitis: Troponin C2, Fast Skeletal Type (TNNC2) and Calcium Signaling Pathway.

BACKGROUND Ankylosing spondylitis (AS) is a disease that causes pathological changes in the spine and sacroiliac joints. Numerous studies have shown that the characteristics of AS differ between males and females. The purpose of this study was to discover the key molecules that contribute to sex-associated differences in AS, which may provide a new molecular target for personalized treatment. MATERIAL AND METHODS The gene expression profile of GSE39340 was downloaded from the Gene Expression Comprehensive database, and 2 groups (AS vs. No-AS groups and male AS vs. female AS groups) of differentially expressed genes (EDGs) were obtained by GEO2R. The DAVID database was used for DEGs function and enrichment analysis. Based on data in the STRING online database, a protein-protein interaction (PPI) network was constructed in Cytoscape. Hub genes were selected from CytoHubba. With the intersection of the top 30 hub genes of 2 sets of EDGs, genes coexisting with the KEGG-related pathway were found. RESULTS We screened 560 genes between the AS and No-AS groups, and screened 710 genes that were differentially expressed between the male and female AS groups. GO analysis showed that DEGs were mainly co-enriched in molecular functions, including structural constituent of muscle. The KEGG pathway mainly included the structural constituent of muscle. Seven hub genes were obtained. Troponin C2 and fast skeletal type (TNNC2) were the key genes participating in the calcium signaling pathway. CONCLUSIONS This study contributes to understanding the molecular biological mechanism underlying sex-associated differences in AS. TNNC2 and calcium signaling pathway may be new targets for the individualized treatment of AS.

Long non-coding RNA reprogramming (lncRNA-ROR) regulates cell apoptosis and autophagy in chondrocytes.

Long Non-Coding RNA Reprogramming (lncRNA-ROR) plays an important role in regulating various biologic processes, whereas the effect of lncRNA-ROR in osteoarthritis (OA) is little studied. This study aimed to explore lncRNA-ROR expression in articular cartilage and identify the functional mechanism of lncRNA-ROR in OA. OA cartilage tissues were obtained from 15 OA patients, and 6 normal cartilage tissues were set as controls. Chondrocytes were isolated from the collected cartilage tissues. lncRNA-ROR was knockdown in normal cells and overexpressed in OA cells. Cell viability was determined with Cell Counting Kit-8 assay, and apoptosis was measured using flow cytometric analysis. Moreover, proteins and mRNAs involved in this study were also measured using Western blotting and quantitative real-time PCR (qPCR). Level of lncRNA-ROR was decreased in OA compared with normal chondrocytes, and overexpression of lncRNA-ROR dramatically promoted cell viability of OA chondrocytes. In addition, knockdown lncRNA-ROR inhibited apoptosis and promoted autophagy of normal chondrocytes. Moreover, lncRNA-ROR inhibited the expression of p53 in both mRNA and protein levels. Furthermore, we revealed that lncRNA-ROR regulated apoptosis and autophagy of chondrocytes via HIF1α and p53. The results indicated that lncRNA-ROR played a critical role in the pathogenesis of OA, suggesting that lncRNA-ROR could serve as a new potential therapeutic target for OA.

Plant G proteins interact with endoplasmic reticulum luminal protein receptors to regulate endoplasmic reticulum retrieval.

Maintaining endoplasmic reticulum (ER) homeostasis is essential for the production of biomolecules. ER retrieval, i.e., the retrograde transport of compounds from the Golgi to the ER, is one of the pathways that ensures ER homeostasis. However, the mechanisms underlying the regulation of ER retrieval in plants remain largely unknown. Plant ERD2-like proteins (ERD2s) were recently suggested to function as ER luminal protein receptors that mediate ER retrieval. Here, we demonstrate that heterotrimeric G protein signaling is involved in ERD2-mediated ER retrieval. We show that ERD2s interact with the heterotrimeric G protein Gα and Gγ subunits at the Golgi. Silencing of Gα, Gß, or Gγ increased the retention of ER luminal proteins. Furthermore, overexpression of Gα, Gß, or Gγ caused ER luminal proteins to escape from the ER, as did the co-silencing of ERD2a and ERD2b. These results suggest that G proteins interact with ER luminal protein receptors to regulate ER retrieval.

Vibration characteristics of golf club heads in their handheld grinding process and potential approaches for reducing the vibration exposure.

To control vibration-induced white finger among workers performing the fine grinding of golf club heads, the aims of this study are to clarify the major vibration sources in the grinding process, to identify and understand the basic characteristics of the club head vibration, and to propose potential approaches for reducing the vibration exposure. The vibrations on two typical club heads and two belt grinding machines were measured at a workplace. A simulated test station was also constructed and used to help examine some influencing factors of the club head vibration. This study found that the club head vibration was the combination of the vibration transmitted from the grinding machines and that generated in the grinding process. As a result, any factor that affects the machine vibration, the grinding vibration, and/or the dynamic response of the club head can influence the vibration exposure of the fingers or hands holding the club head in the grinding process. The significant influencing factors identified in the study include testing subject, grinding machine, machine operation speed, drive wheel condition, club head model, mechanical constraints imposed on the club head during the grinding, and machine foot pad. These findings suggest that the vibration exposure can be controlled by reducing the grinding machine vibration, changing the workpiece dynamic properties, and mitigating the vibration transmission in its pathway. Many potential methods for the control are proposed and discussed. RELEVANCE TO INDUSTRY: Vibrations on handheld workpieces can be effectively transmitted to the hands, especially the fingers. As a result, a major component of the hand-arm vibration syndrome - vibration-induced white finger - has been observed among some workers performing the grinding and/or polishing tasks of the handheld workpieces such as golf club heads. The results of this study can be used to develop more effective methods and technologies to control the vibration exposure of these workers. This may help effectively control this occupational disease.

Translation machinery: the basis of translational control.

Messenger RNA (mRNA) translation consists of initiation, elongation, termination, and ribosome recycling, carried out by the translation machinery, primarily including tRNAs, ribosomes, and translation factors (TrFs). Translational regulators transduce signals of growth and development, as well as biotic and abiotic stresses, to the translation machinery, where global or selective translational control occurs to modulate mRNA translation efficiency (TrE). As the basis of translational control, the translation machinery directly determines the quality and quantity of newly synthesized peptides and, ultimately, the cellular adaption. Thus, regulating the availability of diverse machinery components is reviewed as the central strategy of translational control. We provide classical signaling pathways (e.g., integrated stress responses) and cellular behaviors (e.g., liquid-liquid phase separation) to exemplify this strategy within different physiological contexts, particularly during host-microbe interactions. With new technologies developed, further understanding this strategy will speed up translational medicine and translational agriculture.

RNAirport: a deep neural network-based database characterizing representative gene models in plants.

A 5'-leader, known initially as the 5'-untranslated region, contains multiple isoforms due to alternative splicing (aS) and alternative transcription start site (aTSS). Therefore, a representative 5'-leader is demanded to examine the embedded RNA regulatory elements in controlling translation efficiency. Here, we develop a ranking algorithm and a deep-learning model to annotate representative 5'-leaders for five plant species. We rank the intra-sample and inter-sample frequency of aS-mediated transcript isoforms using the Kruskal-Wallis test-based algorithm and identify the representative aS-5'-leader. To further assign a representative 5'-end, we train the deep-learning model 5'leaderP to learn aTSS-mediated 5'-end distribution patterns from cap-analysis gene expression data. The model accurately predicts the 5'-end, confirmed experimentally in Arabidopsis and rice. The representative 5'-leader-contained gene models and 5'leaderP can be accessed at RNAirport (http://www.rnairport.com/leader5P/). The Stage 1 annotation of 5'-leader records 5'-leader diversity and will pave the way to Ribo-Seq open-reading frame annotation, identical to the project recently initiated by human GENCODE.