Activation of polyamine catabolism promotes glutamine metabolism and creates a targetable vulnerability in lung cancer.

Polyamines are a class of small polycationic alkylamines that play essential roles in both normal and cancer cell growth. Polyamine metabolism is frequently dysregulated and considered a therapeutic target in cancer. However, targeting polyamine metabolism as monotherapy often exhibits limited efficacy, and the underlying mechanisms are incompletely understood. Here we report that activation of polyamine catabolism promotes glutamine metabolism, leading to a targetable vulnerability in lung cancer. Genetic and pharmacological activation of spermidine/spermine N1-acetyltransferase 1 (SAT1), the rate-limiting enzyme of polyamine catabolism, enhances the conversion of glutamine to glutamate and subsequent glutathione (GSH) synthesis. This metabolic rewiring ameliorates oxidative stress to support lung cancer cell proliferation and survival. Simultaneous glutamine limitation and SAT1 activation result in ROS accumulation, growth inhibition, and cell death. Importantly, pharmacological inhibition of either one of glutamine transport, glutaminase, or GSH biosynthesis in combination with activation of polyamine catabolism synergistically suppresses lung cancer cell growth and xenograft tumor formation. Together, this study unveils a previously unappreciated functional interconnection between polyamine catabolism and glutamine metabolism and establishes cotargeting strategies as potential therapeutics in lung cancer.

RNA-binding motif protein 10 inactivates c-Myc by partnering with ribosomal proteins uL18 and uL5.

RNA-binding motif protein 10 (RBM10) is a frequently mutated tumor suppressor in lung adenocarcinoma (LUAD). Yet, it remains unknown whether cancer-derived mutant RBM10 compromises its tumor suppression function and, if so, the molecular insight of the underlying mechanisms. Here, we show that wild-type RBM10 suppresses lung cancer cell growth and proliferation by inactivating c-Myc that is essential for cancer cell survival. RBM10 directly binds to c-Myc and promotes c-Myc's ubiquitin-dependent degradation, while RBM10 knockdown leads to the induction of c-Myc level and activity. This negative action on c-Myc is further boosted by ribosomal proteins (RPs) uL18 (RPL5) and uL5 (RPL11) via their direct binding to RBM10. Cancer-derived mutant RBM10-I316F fails to bind to uL18 and uL5 and to inactivate c-Myc, thus incapable of suppressing tumorigenesis. Our findings uncover RBM10 as a pivotal c-Myc repressor by cooperating with uL18 and uL5 in lung cancer cells, as its failure to do so upon mutation favors tumorigenesis.

Inner filter effect-based near-infrared fluorescent probe for detection of metronidazole on a smartphone-integrated analytical platform.

Antibiotic residues pose a serious threat to ecosystems and food safety. Developing convenient, visual, and on-site detection methods is therefore in high demand and has a practical purpose. In this work, a near-infrared (NIR) fluorescent probe with an analysis platform based on a smartphone has been constructed for quantitative and on-site detection of metronidazole (MNZ). CdTe quantum dots with NIR emission at 710 nm (QD710) were prepared by using a simple hydrothermal method and showed good properties. A spectral overlap between absorption of MNZ and excitation of QD710 resulted in an effective inner filter effect (IFE) between QD710 and MNZ. Because of the IFE, the fluorescence of QD710 decreased gradually with increasing concentrations of MNZ. Based on the fluorescence response, quantitative detection and visualization of MNZ was achieved. NIR fluorescence analysis and the special IFE between probe and target can improve sensitivity and selectivity for MNZ. Additionally, these were also utilized for quantitative detection of MNZ in real food samples and the results were reliable and satisfactory. Meanwhile, a portable visual analysis platform in a smartphone was constructed for on-site analysis of MNZ, which can be used as an alternative method for detection of MNZ residues in situations with limited instrumental conditions. Therefore, this work provides a convenient, visual, and real-time analysis method for detection of MNZ and the analysis platform shows great potential for commercialization.

Analysis of the histidine kinase gene family and the role of GhHK8 in response to drought tolerance in cotton.

As an important member of the two-component system (TCS), histidine kinases (HKs) play important roles in various plant developmental processes and signal transduction in response to a wide range of biotic and abiotic stresses. So far, the HK gene family has not been investigated in Gossypium. In this study, a total of 177 HK gene family members were identified in cotton. They were further divided into seven groups, and the protein characteristics, genetic relationship, gene structure, chromosome location, collinearity, and cis-elements identification were comprehensively analyzed. Whole genome duplication (WGD) / segmental duplication may be the reason why the number of HK genes doubled in tetraploid Gossypium species. Expression analysis revealed that most cotton HK genes were mainly expressed in the reproductive organs and the fiber at initial stage. Gene expression analysis revealed that HK family genes are involved in cotton abiotic stress, especially drought stress and salt stress. In addition, gene interaction networks showed that HKs were involved in the regulation of cotton abiotic stress, especially drought stress. VIGS experiments have shown that GhHK8 is a negative regulatory factor in response to drought stress. Our systematic analysis provided insights into the characteristics of the HK genes in cotton and laid a foundation for further exploring their potential in drought stress resistance in cotton.

Meta-genome analysis of a newly enriched azo dyes detoxification halo-thermophilic bacterial consortium.

Treating textile wastewaters were always inhibited by its higher salt concentration and temperature. In this study, a halo-thermophilic bacterial consortium YM was enriched with ability to decolorize acid brilliant scarlet GR (ABS) at 55 °C and 10% salinity. Under optimum conditions of pH (8), temperature (55 °C), and salinity (10%), YM decolorized 97% of ABS under anaerobic conditions. Alteribacillus was identified to be the dominant genus in consortium YM. Consortium YM showed significant decolorization ability under a wide range of salinity (1%-10%), pH (7-9) and temperature (45 °C-60 °C). The degradation pathway of ABS was proposed by the combination of UV-vis spectral analysis, Fourier transform infrared (FTIR), gas chromatography mass spectrometric (GC-MS), and metagenomic analysis. Azoreductase, which was an important enzyme in decolorization process, was identified with great variation in the genome of consortium YM. Meanwhile, the metabolic intermediates after decolorization was identified with low biotoxicity by phytotoxicity tests. This study first identified that Alterbacillus play an important role in azo dye decolorization and degradation process under halo-thermophlic conditions and provided significant knowledge for azo dye decolorization and degradation process.

Comparative Efficacy and Safety of Thrombolytic Agents for Pulmonary Embolism: A Bayesian Network Meta-Analysis.

BACKGROUND: Thrombolytic agents and anticoagulants are the two classes of medication used in the treatment of acute pulmonary embolism (PE). There is continuous renewal and iteration of thrombolytic agents, and the efficacy and adverse effects of different agents have different effects on PE due to their different mechanisms of action. OBJECTIVES: The aim of the study was to evaluate the efficacy and safety of different thrombolytic agents in the treatment of all types of acute PE: hemodynamically unstable PE (massive PE) and hemodynamically stable PE (submassive PE and low-risk PE), using a network meta-analysis. METHODS: A search was conducted of the following databases: PubMed, The Cochrane Library, Embase, and Web of Science to collect randomized controlled trials (RCTs) comparing thrombolytic agents with heparin or other thrombolytic agents in patients with acute PE; the clinical outcomes included patient mortality, recurrent PE, pulmonary artery systolic pressure (PASP) after treatment, and major and minor bleeding. The measurement duration of outcome indicators was the longest follow-up period. Thereafter, a network meta-analysis was performed using a Bayesian network framework. RESULTS: A total of 29 RCTs (3,067 patients) were included, of which 6 studies (304 patients) were massive PE, 14 studies (2,173 patients) were submassive PE, 1 study (83 patients) included massive and submassive PE, and 8 studies (507 patients) were PE of unknown type. The treatment regimens included thrombolytic therapy (alteplase, reteplase, tenecteplase, streptokinase, and urokinase) and anticoagulant therapy alone. The results showed that the mortality using thrombolytic agents (except tenecteplase) was significantly lower compared with heparin. The recurrence of PE with alteplase was significantly lower compared with heparin (RR = 0.23, 95% CI, 0.04, 0.65). The PASP after using alteplase was significantly lower compared with heparin (mean difference = -11.36, 95% CI, -21.45, -1.56). Compared with heparin, the incidence of minor bleeding associated with tenecteplase was higher (RR = 3.27, 95% CI, 1.36, 7.39); compared with streptokinase, the incidence of minor bleeding associated with tenecteplase was higher (RR = 3.22, 95% CI, 1.01, 11.10). CONCLUSION: For patients with acute PE, four thrombolytic agents (alteplase, reteplase, streptokinase, and urokinase) appeared to be superior in efficacy compared with anticoagulants alone due to a reduction in mortality and no increase in bleeding risk. Alteplase may be a better choice because it not only reduced mortality but also reduced PE recurrence rate and treated PASP. Tenecteplase did not reduce mortality compared with anticoagulants alone and may not be a good choice of thrombolytic agent due to an increase in minor bleeding compared with streptokinase and anticoagulants alone. Thrombolytic drugs should be rationally selected to optimize the thrombolytic regimen and achieve as good a balance as possible between thrombolysis and bleeding.

The Role of the Cerebellum in Drug Reward: A Review.

Drug abuse remains a global problem; nonetheless, its mechanism has not yet been fully understood. Recent studies have reported on the non-motor functions of the cerebellum, and evidence from neuroimaging and behavioral studies has suggested the role of cerebellum in drug reward, which has received increasing attention. Furthermore, emerging technological developments have aided in clarifying the various circuits and functions of the cerebellum. Exploring the role of the cerebellum in drug reward can improve our understanding of the mechanism underlying addiction and facilitate the development of new treatment schemes. This review summarizes the anatomy of the cerebellum and its connections to brain regions considered important in addiction. Subsequently, we investigate the neurological reasons elucidating why the cerebellum is a potential target for drug reward. Additionally, we expound the molecular targets of addictive drugs in the cerebellum, mainly glutamate and endocannabinoids. Unlike previous studies, this article focuses on the influence of alcohol, nicotine, morphine, cannabis, and cocaine on the cerebellum from multiple viewpoints, including imaging and behavioral changes, molecular signals, neurotransmitters, and synaptic transmission. We aim to clarify some drug-induced cerebellar changes to supplement the previous research regarding the relationship between addiction and the cerebellum. Finally, we discuss the limitations and prospects of drug reward research on the cerebellum to provide novel insights into studying the cerebellum and its role in addiction. We recommend that future addiction network models should include the cerebellum to provide new therapeutic targets for treating addiction.

Carbon dot and silver nanoparticle-based fluorescent probe for the determination of sulfite and bisulfite via inner-filter effect and competitive redox reactions.

A new sensitive fluorescent probe (CDs-AgNP/H2O2) for detecting sulfite and bisulfite (SO32- and HSO3-) based on the inner-filter effect (IFE) between silver nanoparticles (AgNPs) and carbon dots (CDs) was developed. Because of the spectral overlap between the absorption of AgNPs and the excitation of CDs, the fluorescence of CDs can be quenched by AgNPs owing to the IFE. H2O2 weakens the IFE and restores the fluorescence due to the oxidation of AgNPs by H2O2. However, the existence of SO32-/HSO3- can quench the fluorescence again as a result of redox reaction between SO32-/HSO3- and H2O2. The results showed a broad linear range of 20-200 µM with a low limit of detection (3.02 µM) toward SO32-/HSO3-. The combination of IFE and redox reaction led to improvement of the sensitivity and selectivity. The probe was implemented to measure SO32-/HSO3- in various agricultural products and foods with acceptable results (80.6 to 118.9% recovery).

Secondary metabolite pathway of SDG (secoisolariciresinol) was observed to trigger ROS scavenging system in response to Ca2+ stress in cotton.

Ca2+ is an essential nutrient for plants and animals which plays an important role in plant signal transduction. Although the function and regulation of mechanism of Ca2+ in alleviating various biotic and abiotic stresses in plants have been studied deeply, the molecular mechanism to adapt high Ca2+ stress is still unclear in cotton. In this study, 103 cotton accessions were germinated under 200 mM CaCl2 stress, and two extremely Ca2+-resistant (Zhong 9807, R) and Ca2+-sensitive (CRI 50, S) genotypes were selected from 103 cotton accessions. The two accessions were then germinated for 5 days in 0 mM CaCl2 and 200 mM CaCl2 respectively, after which they were sampled for transcriptome sequencing. Morphological and physiological analyses suggested that PLR2 specifically expressed in R may enhance the ability of cotton to scavenge ROS by promoting the synthesis of SDG. In conclusion, this study proposed the adaptation mechanisms to response to the high Ca2+ stress in cotton which can contribute to improve the stress resistance of cotton.

Genome-Wide Analysis and Functional Characterization of LACS Gene Family Associated with Lipid Synthesis in Cotton (Gossypium spp.).

Cotton (Gossypium spp.) is the fifth largest oil crop in the world, and cottonseed provides abundant vegetable oil resources and industrial bioenergy fuels for people; therefore, it is of practical significance to increase the oil content of cotton seeds for improving the oil yield and economic benefits of planting cotton. Long-chain acyl-coenzyme A (CoA) synthetase (LACS) capable of catalyzing the formation of acyl-CoAs from free fatty acids has been proven to significantly participate in lipid metabolism, of which whole-genome identification and functional characterization of the gene family have not yet been comprehensively analyzed in cotton. In this study, a total of sixty-five LACS genes were confirmed in two diploid and two tetraploid Gossypium species, which were divided into six subgroups based on phylogenetic relationships with twenty-one other plants. An analysis of protein motif and genomic organizations displayed structural and functional conservation within the same group but diverged among the different group. Gene duplication relationship analysis illustrates the LACS gene family in large scale expansion through WGDs/segmental duplications. The overall Ka/Ks ratio indicated the intense purifying selection of LACS genes in four cotton species during evolution. The LACS genes promoter elements contain numerous light response cis-elements associated with fatty acids synthesis and catabolism. In addition, the expression of almost all GhLACS genes in high seed oil were higher compared to those in low seed oil. We proposed LACS gene models and shed light on their functional roles in lipid metabolism, demonstrating their engineering potential for modulating TAG synthesis in cotton, and the genetic engineering of cottonseed oil provides a theoretical basis.

The Application of Computer Technology to Clinical Practice Guideline Implementation: A Scoping Review.

Implementation of clinical practice guidelines (CPG) is a complex and challenging task. Computer technology, including artificial intelligence (AI), has been explored to promote the CPG implementation. This study has reviewed the main domains where computer technology and AI has been applied to CPG implementation. PubMed, Embase, Web of science, the Cochrane Library, China National Knowledge Infrastructure database, WanFang DATA, VIP database, and China Biology Medicine disc database were searched from inception to December 2021. Studies involving the utilization of computer technology and AI to promote the implementation of CPGs were eligible for review. A total of 10429 published articles were identified, 117 met the inclusion criteria. 21 (17.9%) focused on the utilization of AI techniques to classify or extract the relative content of CPGs, such as recommendation sentence, condition-action sentences. 47 (40.2%) focused on the utilization of computer technology to represent guideline knowledge to make it understandable by computer. 15 (12.8%) focused on the utilization of AI techniques to verify the relative content of CPGs, such as conciliation of multiple single-disease guidelines for comorbid patients. 34 (29.1%) focused on the utilization of AI techniques to integrate guideline knowledge into different resources, such as clinical decision support systems. We conclude that the application of computer technology and AI to CPG implementation mainly concentrated on the guideline content classification and extraction, guideline knowledge representation, guideline knowledge verification, and guideline knowledge integration. The AI methods used for guideline content classification and extraction were pattern-based algorithm and machine learning. In guideline knowledge representation, guideline knowledge verification, and guideline knowledge integration, computer techniques of knowledge representation were the most used.

The causal association between smoking, alcohol consumption and risk of bladder cancer: A univariable and multivariable Mendelian randomization study.

Smoking and alcohol consumption are associated with bladder cancer risk in observational studies. We conducted a two-sample univariable and multivariable Mendelian randomization (MR) analysis to determine whether those associations are causal. We used 21, 126, 360, 39 single nucleotide polymorphisms (SNPs) as instrumental variables for number of cigarettes per day, lifetime smoking index, smoking initiation, and drinks per week, respectively. A total of 1115 cases with bladder cancer and 174 006 noncases from FinnGen consortium and 2883 cases with bladder cancer and 417 955 noncases from UK Biobank study were obtained. Genetic predisposition to cigarettes per day, lifetime smoking index and smoking initiation were positively associated with an increased risk of bladder cancer in both the FinnGen and UK Biobank consortium. The summary odds ratio (OR) of bladder cancer was 1.79 (95% confidence interval [CI], 1.31-2.45; P = .0002), 2.38 (95% CI, 1.45-3.88; P = .0005) and 1.91 (95% CI, 1.46-2.50; P = 1.59 × 10-06 ) for one SD increase in the number of cigarettes per day, lifetime smoking index and smoking initiation, respectively. The genetically instrumented number of drinks per week was not associated with bladder cancer (OR = 0.69; 95% CI, 0.44-1.10; P = .1237). Estimates were consistent in multivariable MR analyses by the adjustments of body mass index and education. Our study suggests a causal potential of the association of smoking but not alcohol consumption with bladder cancer according to current evidence.

Causal relationship between obesity, lifestyle factors and risk of benign prostatic hyperplasia: a univariable and multivariable Mendelian randomization study.

BACKGROUND: Obesity (waist circumference, body mass index (BMI)) and lifestyle factors (dietary habits, smoking, alcohol drinking, Sedentary behavior) have been associated with risk of benign prostatic hyperplasia (BPH) in observational studies, but whether these associations are causal is unclear. METHODS: We performed a univariable and multivariable Mendelian randomization study to evaluate these associations. Genetic instruments associated with exposures at the genome-wide significance level (P < 5 × 10-8) were selected from corresponding genome-wide associations studies (n = 216,590 to 1,232,091 individuals). Summary-level data for BPH were obtained from the UK Biobank (14,126 cases and 169,762 non-cases) and FinnGen consortium (13,118 cases and 72,799 non-cases). Results from UK Biobank and FinnGen consortium were combined using fixed-effect meta-analysis. RESULTS: The combined odds ratios (ORs) of BPH were 1.24 (95% confidence interval (CI), 1.07-1.43, P = 0.0045), 1.08 (95% CI 1.01-1.17, P = 0.0175), 0.94 (95% CI 0.67-1.30, P = 0.6891), 1.29 (95% CI 0.88-1.89, P = 0.1922), 1.23 (95% CI 0.85-1.78, P = 0.2623), and 1.04 (95% CI 0.76-1.42, P = 0.8165) for one standard deviation (SD) increase in waist circumference, BMI, and relative carbohydrate, fat, protein and sugar intake, 1.05 (95% CI 0.92-1.20, P = 0.4581) for one SD increase in prevalence of smoking initiation, 1.10 (95% CI 0.96-1.26, P = 0.1725) and 0.84 (95% CI 0.69-1.02, P = 0.0741) for one SD increase of log-transformed smoking per day and drinks per week, and 1.31 (95% CI 1.08-1.58, P = 0.0051) for one SD increase in sedentary behavior. Genetically predicted waist circumference (OR = 1.26, 95% CI 1.11-1.43, P = 0.0004) and sedentary behavior (OR = 1.14, 95% CI 1.05-1.23, P = 0.0021) were associated with BPH after the adjustment of BMI. CONCLUSION: This study supports independent causal roles of high waist circumference, BMI and sedentary behavior in BPH.

Fast physical random bit generation based on a chaotic optical injection system with multi-path optical feedback.

Based on the chaotic signal provided by a simple chaotic system, a random bit sequence with a rate of 640 Gb/s is generated through adopting the circulating exclusive-or (CXOR) post-processing method. Such a simple chaotic system is built via a slave semiconductor laser subject to optical injection of a chaotic signal originated from a master semiconductor laser under multi-path optical feedback. First, through inspecting the dependences of the time-delay-signature (TDS) and bandwidth of the chaotic signal on some key operation parameters, optimized parameters are determined for generating a high-quality chaotic signal with a large bandwidth and low TDS. Second, the high-quality chaotic signal is converted to an 8-bit digital signal by sampling with a digital oscilloscope at 80 GSa/s. Next, through adopting the CXOR post-processing method, a bit sequence with a rate of 640 Gb/s is obtained. Finally, the randomness is estimated by the National Institute of Standard Technology (NIST) Special Publication 800-22 statistical tests, and the results demonstrate that the obtained random bit sequence can pass all the NIST tests.

FAM46B is a prokaryotic-like cytoplasmic poly(A) polymerase essential in human embryonic stem cells.

Family with sequence similarity (FAM46) proteins are newly identified metazoan-specific poly(A) polymerases (PAPs). Although predicted as Gld-2-like eukaryotic non-canonical PAPs, the detailed architecture of FAM46 proteins is still unclear. Exact biological functions for most of FAM46 proteins also remain largely unknown. Here, we report the first crystal structure of a FAM46 protein, FAM46B. FAM46B is composed of a prominently larger N-terminal catalytic domain as compared to known eukaryotic PAPs, and a C-terminal helical domain. FAM46B resembles prokaryotic PAP/CCA-adding enzymes in overall folding as well as certain inter-domain connections, which distinguishes FAM46B from other eukaryotic non-canonical PAPs. Biochemical analysis reveals that FAM46B is an active PAP, and prefers adenosine-rich substrate RNAs. FAM46B is uniquely and highly expressed in human pre-implantation embryos and pluripotent stem cells, but sharply down-regulated following differentiation. FAM46B is localized to both cell nucleus and cytosol, and is indispensable for the viability of human embryonic stem cells. Knock-out of FAM46B is lethal. Knock-down of FAM46B induces apoptosis and restricts protein synthesis. The identification of the bacterial-like FAM46B, as a pluripotent stem cell-specific PAP involved in the maintenance of translational efficiency, provides important clues for further functional studies of this PAP in the early embryonic development of high eukaryotes.

Clinical research capability enhanced for medical undergraduates: an innovative simulation-based clinical research curriculum development.

BACKGROUND: Clinical research has frequently not been taught in a practical way, often resulting in a very didactic approach rendering it not very accessible for medical undergraduates. Simulation can provide an immersive, interactive, and reflective experience and may be applied to the clinical research curriculum. METHODS: A 7-step model, modified from Kern's six-step approach and Khamis's stepwise model, was used to develop the curriculum. A questionnaire survey on undergraduates' attitude towards, knowledge and practice of clinical research and simulation education was conducted to generate a targeted needs assessment. The simulation framework was integrated into the development of educational strategies. Experts were consulted to assess the curriculum prior to implementation. RESULTS: Talent construction in China needs an innovative capability-enhanced clinical research curriculum. Sixty-six clinical undergraduates in our school completed the survey. 89.39% (59/66) of them hadn't participated in clinical research, while 93.94% (62/66) would like to conduct clinical trials if possible. 75.76% of respondents didn't have knowledge of or practical abilities in clinical trials. The mean score for practical ability (2.02 ± 0.92) was lower than that of knowledge (2.20 ± 0.93) (P < 0.01). The dimension of case report form got the lowest score among the five dimensions. Participating in clinical research (P = 0.04) and learning for themselves (P < 0.01) by a few students may have increased the total score. The curriculum was designed to simulate the whole process from protocol writing, registration, ethical approval, implementation, and data analysis to reporting based on one case study, and was divided into two parts to simulate different types of research: randomized controlled trials and observational studies. It was conducted in semesters 5 and 7 respectively, both including 16 sessions. After expert consultation, one session having a 29.01% coefficient of variation was adjusted and replaced. The final simulation class design scenario scripts are provided for reference. CONCLUSIONS: The targeted needs assessment exposed medical undergraduates' poor knowledge of and abilities in clinical research. This is the first report of a simulation-based clinical research curriculum developed in China, and adds curriculum development and design details to the limited related published studies.

Quantitative Evaluation of In Vivo Corneal Biomechanical Properties after SMILE and FLEx Surgery by Acoustic Radiation Force Optical Coherence Elastography.

The purpose of this study is to quantitatively evaluate the differences in corneal biomechanics after SMILE and FLEx surgery using an acoustic radiation force optical coherence elastography system (ARF-OCE) and to analyze the effect of the corneal cap on the integrity of corneal biomechanical properties. A custom ring array ultrasound transducer is used to excite corneal tissue to produce Lamb waves. Depth-resolved elastic modulus images of the in vivo cornea after refractive surgery were obtained based on the phase velocity of the Lamb wave. After refractive surgery, the average elastic modulus of the corneal flap decreased (71.7 ± 24.6 kPa), while the elastic modulus of the corneal cap increased (219.5 ± 54.9 kPa). The average elastic modulus of residual stromal bed (RSB) was increased after surgery, and the value after FLEx (305.8 ± 48.5 kPa) was significantly higher than that of SMILE (221.3 ± 43.2 kPa). Compared with FLEx, SMILE preserved most of the anterior stroma with less change in corneal biomechanics, which indicated that SMILE has an advantage in preserving the integrity of the corneal biomechanical properties. Therefore, the biomechanical properties of the cornea obtained by the ARF-OCE system may be one of the essential indicators for evaluating the safety of refractive surgery.

Integrated Analysis of Microarray, Small RNA, and Degradome Datasets Uncovers the Role of MicroRNAs in Temperature-Sensitive Genic Male Sterility in Wheat.

Temperature-sensitive genic male sterile (TGMS) line Beijing Sterility 366 (BS366) has been utilized in hybrid breeding for a long time, but the molecular mechanism underlying male sterility remains unclear. Expression arrays, small RNA, and degradome sequencing were used in this study to explore the potential role of miRNA in the cold-induced male sterility of BS366. Microspore observation showed defective cell plates in dyads and tetrads and shrunken microspores at the vacuolated stage. Differential regulation of Golgi vesicle transport, phragmoplast formation, sporopollenin biosynthesis, pollen exine formation, and lipid metabolism were observed between cold and control conditions. Pollen development was significantly represented in the 352 antagonistic miRNA-target pairs in the integrated analysis of miRNA and mRNA profiles. The specific cleavage of ARF17 and TIR1 by miR160 and miR393 were found in the cold-treated BS366 degradome, respectively. Thus, the cold-mediated miRNAs impaired cell plate formation through repression of Golgi vesicle transport and phragmoplast formation. The repressed expression of ARF17 and TIR1 impaired pollen exine formation. The results of this study will contribute to our understanding of the roles of miRNAs in male sterility in wheat.

Comparative transcriptome and DNA methylation analysis in temperature-sensitive genic male sterile wheat BS366.

BACKGROUND: Known as the prerequisite component for the heterosis breeding system, the male sterile line determines the hybrid yield and seed purity. Therefore, a deep understanding of the mechanism and gene network that leads to male sterility is crucial. BS366, a temperature-sensitive genic male sterile (TGMS) line, is male sterile under cold conditions (12 °C with 12 h of daylight) but fertile under normal temperature (20 °C with 12 h of daylight). RESULTS: During meiosis, BS366 was defective in forming tetrads and dyads due to the abnormal cell plate. During pollen development, unusual vacuolated pollen that could not accumulate starch grains at the binucleate stage was also observed. Transcriptome analysis revealed that genes involved in the meiotic process, such as sister chromatid segregation and microtubule-based movement, were repressed, while genes involved in DNA and histone methylation were induced in BS366 under cold conditions. MethylRAD was used for reduced DNA methylation sequencing of BS366 spikes under both cold and control conditions. The differentially methylated sites (DMSs) located in the gene region were mainly involved in carbohydrate and fatty acid metabolism, lipid metabolism, and transport. Differentially expressed and methylated genes were mainly involved in cell division. CONCLUSIONS: These results indicated that the methylation of genes involved in carbon metabolism or fatty acid metabolism might contribute to male sterility in BS366 spikes, providing novel insight into the molecular mechanism of wheat male sterility.

Genome-wide identification and transcriptional characterization of DNA methyltransferases conferring temperature-sensitive male sterility in wheat.

BACKGROUND: DNA methyltransferase (DMT) genes contribute to plant stress responses and development by de novo establishment and subsequent maintenance of DNA methylation during replication. The photoperiod and/or temperature-sensitive genic male sterile (P/TGMS) lines play an important role in hybrid seed production of wheat. However, only a few studies have reported on the effect of DMT genes on temperature-sensitive male sterility of wheat. Although DMT genes have been investigated in some plant species, the identification and analysis of DMT genes in wheat (Triticum aestivum L.) based on genome-wide levels have not been reported. RESULTS: In this study, a detailed overview of phylogeny of 52 wheat DMT (TaDMT) genes was presented. Homoeolog retention for TaDMT genes was significantly above the average retention rate for whole-wheat genes, indicating the functional importance of many DMT homoeologs. We found that the strikingly high number of TaDMT genes resulted mainly from the significant expansion of the TaDRM subfamily. Intriguingly, all 5 paralogs belonged to the wheat DRM subfamily, and we speculated that tandem duplications might play a crucial role in the TaDRM subfamily expansion. Through the transcriptional analysis of TaDMT genes in a TGMS line BS366 and its hybrids with the other six fertile lines under sterile and fertile conditions, we concluded that TaCMT-D2, TaMET1-B1, and TaDRM-U6 might be involved in male sterility in BS366. Furthermore, a correlation analysis showed that TaMET1-B1 might negatively regulate the expression of TaRAFTIN1A, an important gene for pollen development, so we speculated regarding an epigenetic regulatory mechanism underlying the male sterility of BS366 via the interaction between TaMET1-B1 and TaRAFTIN1A. CONCLUSIONS: Our findings presented a detailed phylogenic overview of the DMT genes and could provide novel insights into the effects of DMT genes on TGMS wheat.