Unlocking saponin biosynthesis in soapwort.

Soapwort (Saponaria officinalis) is a flowering plant from the Caryophyllaceae family with a long history of human use as a traditional source of soap. Its detergent properties are because of the production of polar compounds (saponins), of which the oleanane-based triterpenoid saponins, saponariosides A and B, are the major components. Soapwort saponins have anticancer properties and are also of interest as endosomal escape enhancers for targeted tumor therapies. Intriguingly, these saponins share common structural features with the vaccine adjuvant QS-21 and, thus, represent a potential alternative supply of saponin adjuvant precursors. Here, we sequence the S. officinalis genome and, through genome mining and combinatorial expression, identify 14 enzymes that complete the biosynthetic pathway to saponarioside B. These enzymes include a noncanonical cytosolic GH1 (glycoside hydrolase family 1) transglycosidase required for the addition of D-quinovose. Our results open avenues for accessing and engineering natural and new-to-nature pharmaceuticals, drug delivery agents and potential immunostimulants.

USP18 induction regulates immunometabolism to attenuate M1 signal-polarized macrophages and enhance IL-4-polarized macrophages in systemic lupus erythematosus.

Effective treatment of systemic lupus erythematosus (SLE) remains an unmet need. Different subsets of macrophages play differential roles in SLE and the modulation of macrophage polarization away from M1 status is beneficial for SLE therapeutics. Given the pathogenic roles of type I interferons (IFN-I) in SLE, this study investigated the effects and mechanisms of a mitochondria localization molecule ubiquitin specific peptidase 18 (USP18) preserving anti-IFN effects and isopeptidase activity on macrophage polarization. After observing USP18 induction in monocytes from SLE patients, we studied mouse bone marrow-derived macrophages and showed that USP18 deficiency increased M1signal (LPS + IFN-γ treatment)-induced macrophage polarization, and the effects involved the induction of glycolysis and mitochondrial respiration and the expression of several glycolysis-associated enzymes and molecules, such as hypoxia-inducible factor-1α. Moreover, the effects on mitochondrial activities, such as mitochondrial DNA release and mitochondrial reactive oxygen species production were observed. In contrast, the overexpression of USP18 inhibited M1signal-mediated and enhanced interleukin-4 (IL-4)-mediated polarization of macrophages and the related cellular events. Moreover, the levels of USP18 mRNA expression showed tendency of correlation with the expression of metabolic enzymes in monocytes from patients with SLE. We thus concluded that by preserving anti-IFN effect and downregulating M1 signaling, promoting USP18 activity may serve as a useful approach for SLE therapeutics.

A Visual Positioning Method of UAV in a Large-Scale Outdoor Environment.

Visual positioning is a basic component for UAV operation. The structure-based methods are, widely applied in most literature, based on local feature matching between a query image that needs to be localized and a reference image with a known pose and feature points. However, the existing methods still struggle with the different illumination and seasonal changes. In outdoor regions, the feature points and descriptors are similar, and the number of mismatches will increase rapidly, leading to the visual positioning becoming unreliable. Moreover, with the database growing, the image retrieval and feature matching are time-consuming. Therefore, in this paper, we propose a novel hierarchical visual positioning method, which includes map construction, landmark matching and pose calculation. First, we combine brain-inspired mechanisms and landmarks to construct a cognitive map, which can make image retrieval efficient. Second, the graph neural network is utilized to learn the inner relations of the feature points. To improve matching accuracy, the network uses the semantic confidence in matching score calculations. Besides, the system can eliminate the mismatches by analyzing all the matching results in the same landmark. Finally, we calculate the pose by using a PnP solver. Furthermore, we evaluate both the matching algorithm and the visual positioning method experimentally in the simulation datasets, where the matching algorithm performs better in some scenes. The results demonstrate that the retrieval time can be shortened by three-thirds with an average positioning error of 10.8 m.

Tunable microwave-optical entanglement and conversion in multimode electro-opto-mechanics.

We study tunable double-channel microwave-optical (M-O) entanglement and coherent conversion by controlling the quantum interference effect. This is realized in a two-mechanical-mode electro-opto-mechanical (EOM) system, in which two mechanical resonators (MRs) are coupled with each other by phase-dependent phonon-phonon interaction, and link the interaction between the microwave and optical cavity. It's demonstrated that the mechanical coupling between two MRs leads to the interference of two pathways of electro-opto-mechanical interaction, which can generate the tunable double-channel phenomena in comparison with a typical three-mode EOM system. In particular, by tuning of phonon-phonon interaction and couplings between cavities with MRs, we can not only steer the switch from the M-O interaction with a single channel to that of the double-channel, but also modulate the entanglement and conversion characteristics in each channel. Moreover, our scheme can be extended to an N-mechanical-mode EOM system, in which N discrete channels will be observed and controlled. This study opens up prospects for quantum information transduction and storage with a wide bandwidth and multichannel quantum interface.

Subjective Changes of Taste and Smell in Conjunction With Anxiety and Depression Are Associated With Symptoms in Globus Patients Without Evidence of Pathologic Acid Reflux.

BACKGROUND/AIM: Patients suffering from globus often report decreased enjoyment when eating as well as a psychological abnormality. Some patients exhibit taste and smell changes (TSCs) when compared with the period before the diagnosis. The main aim of this study was to explore if TSCs and psychological abnormality are present in patients with globus, whether they are associated with the severity of throat symptoms, and the potential risk factors for globus. PATIENTS AND METHODS: A total of 116 included patients who met the Rome IV diagnostic criteria for globus had been performed 24-hour pH monitoring, and the results shown no evidence of pathologic acid reflux. Meanwhile, 125 healthy controls were enrolled in this prospective study. All subjects completed several questionnaires including the Taste and Smell Survey, the Glasgow Edinburgh Throat Scale, the Hamilton Anxiety Scale (HAMA), and the Hamilton Depression Scale (HAMD). Multiple logistic regression was performed to explore the potential risk factors for globus. The study protocol was registered on the Chinese Clinical Trial Registry (No. ChiCTR-2100044972). RESULTS: First, globus patients without evidence of pathologic acid reflux exhibited a 58.62% and 31.03% change in taste and smell, respectively, while their levels of anxiety and depression were 51.72% and 44.83%, respectively. Second, there was a significant difference in the taste score (Z=-4.954, P<0.001) and smell score (Z=-4.552, P<0.001) between globus group patients and healthy controls. Similarly, globus group patients had a higher HAMA score (9.52±2.437 vs. 3.12±1.059, t=6.867, P<0.001) and HAMD score (9.79±2.931 vs. 3.16±1.650, t=6.416, P<0.001) when compared with the healthy controls. Third, in globus group patients, the Glasgow Edinburgh Throat Scale was significantly correlated with the taste score (Spearman ρ=0.782; P<0.001), smell score (Spearman ρ=0.582; P=0.001), HAMA (Spearman ρ=0.676; P<0.001), and HAMD (Spearman ρ=0.672; P<0.001). In addition, the taste score was significantly correlated with HAMA (Spearman ρ=0.532; P=0.004) and HAMD (Spearman ρ=0.681; P<0.001), while the smell score was significantly correlated with HAMD (Spearman ρ=0.392; P=0.035). Finally, multivariate logistic regression revealed that TSCs, anxiety, and depression were significant independent risk factors for globus, with depression exhibiting the highest degree of association (odds ratio: 3.244). CONCLUSIONS: TSCs and psychological comorbidities are prominent in globus patients without evidence of pathologic acid reflux. The obtained results indicated that there is a strong relationship between TSCs, psychological comorbidities, and globus. Therefore, awareness of this high prevalence of TSCs and psychological disorder may help to better understand the severity of throat symptoms.

Effect of icosapent ethyl on susceptibility to ventricular arrhythmias in postinfarcted rat hearts: Role of GPR120-mediated connexin43 phosphorylation.

The ω-3 fatty acids exert as an antioxidant via the G protein-coupled receptor 120 (GPR120). Icosapent ethyl, a purified eicosapentaenoic acid, showed a marked reduction in sudden cardiac death. Connexin43 is sensitive to redox status. We assessed whether icosapent ethyl attenuates fatal arrhythmias after myocardial infarction, a status of high oxidative stress, through increased connexin43 expression and whether the GPR120 signalling is involved in the protection. Male Wistar rats after ligating coronary artery were assigned to either vehicle or icosapent ethyl for 4 weeks. The postinfarction period was associated with increased oxidative-nitrosative stress. In concert, myocardial connexin43 levels revealed a significant decrease in vehicle-treated infarcted rats compared with sham. These changes of oxidative-nitrosative stress and connexin43 levels were blunted after icosapent ethyl administration. Provocative arrhythmias in the infarcted rats treated with icosapent ethyl were significantly improved than vehicle. Icosapent ethyl significantly increased GPR120 compared to vehicle after infarction. The effects of icosapent ethyl on superoxide and connexin43 were similar to GPR120 agonist GW9508. Besides, the effects of icosapent ethyl on oxidative-nitrosative stress and connexin43 phosphorylation were abolished by administering AH-7614, an inhibitor of GPR120. SIN-1 abolished the Cx43 phosphorylation of icosapent ethyl without affecting GPR120 levels. Taken together, chronic use of icosapent ethyl after infarction is associated with up-regulation of connexin43 phosphorylation through a GPR120-dependent antioxidant pathway and thus plays a beneficial effect on arrhythmogenic response to programmed electrical stimulation.

The DELLA proteins interact with MYB21 and MYB24 to regulate filament elongation in Arabidopsis.

BACKGROUND: Gibberellin (GA) and jasmonate (JA) are two essential phytohormones for filament elongation in Arabidopsis. GA and JA trigger degradation of DELLAs and JASMONATE ZIM-domain (JAZ) proteins through SCFSLY1 and SCFCOI1 separately to activate filament elongation. In JA pathway, JAZs interact with MYB21 and MYB24 to control filament elongation. However, little is known how DELLAs regulate filament elongation. RESULTS: Here we showed that DELLAs interact with MYB21 and MYB24, and that R2R3 domains of MYB21 and MYB24 are responsible for interaction with DELLAs. Furthermore, we demonstrated that DELLA and JAZ proteins coordinately repress the transcriptional function of MYB21 and MYB24 to inhibit filament elongation. CONCLUSION: We discovered that DELLAs interact with MYB21 and MYB24, and that DELLAs and JAZs attenuate the transcriptional function of MYB21 and MYB24 to control filament elongation. This study reveals a novel cross-talk mechanism of GA and JA in the regulation of filament elongation in Arabidopsis.

Jasmonate action in plant defense against insects.

Herbivorous insects represent one of the major threats to sessile plants. To cope with herbivore challenges, plants have evolved sophisticated defense systems, in which the lipid-derived phytohormone jasmonate plays a crucial role. Perception of insect attack locally and systemically elicits rapid synthesis of jasmonate, which is perceived by the F-box protein COI1 to further recruit JAZ repressors for ubiquitination and degradation, thereby releasing transcription factors that subsequently activate plant defense against insect attack. Here, we review recent progress in understanding the molecular basis of jasmonate action in plant defense against insects.

Identification of cold stress responsive microRNAs in two winter turnip rape (Brassica rapa L.) by high throughput sequencing.

BACKGROUND: Low temperature is a major abiotic stress affecting the production of rapeseed in China by impeding plant growth and development. A comprehensive knowledge of small-RNA expression pattern in Brassica rapa under cold stress could improve our knowledge of microRNA-mediated stress responses. RESULTS: A total of 353 cold-responsive miRNAs, 84 putative novel and 269 conserved miRNAs, were identified from the leaves and roots of two winter turnip rape varieties 'Longyou 7' (cold-tolerant) and 'Tianyou 4' (cold-sensitive), which were stressed under - 4 °C for 8 h. Eight conserved (miR166h-3p-1, miR398b-3p, miR398b-3p-1, miR408d, miR156a-5p, miR396h, miR845a-1, miR166u) and two novel miRNAs (Bra-novel-miR3153-5p and Bra-novel-miR3172-5p) were differentially expressed in leaves of 'Longyou 7' under cold stress. Bra-novel-miR3936-5p was up-regulated in roots of 'Longyou 7' under cold stress. Four and five conserved miRNAs were differentially expressed in leaves and roots of 'Tianyou 4' after cold stress. Besides, we found two conserved miRNAs (miR319e and miR166m-2) were down-regulated in non-stressed roots of 'Longyou 7' compared with 'Tianyou 4'. After cold stress, we found two and eight miRNAs were differentially expressed in leaves and roots of 'Longyou 7' compared with 'Tianyou 4'. The differentially expressed miRNAs between two cultivars under cold stress include novel miRNAs and the members of the miR166 and miR319 families. A total of 211 target genes for 15 known miRNAs and two novel miRNAs were predicted by bioinformatic analysis, mainly involved in metabolic processes and stress responses. Five differentially expressed miRNAs and predicted target genes were confirmed by quantitative reverse transcription PCR, and the expressional changes of target genes were negatively correlated to differentially expressed miRNAs. Our data indicated that some candidate miRNAs (e.g., miR166e, miR319, and Bra-novel-miR3936-5p) may play important roles in plant response to cold stress. CONCLUSIONS: Our work indicates that miRNA and putative target genes mediated metabolic processes and stress responses are significant to cold tolerance in B. rapa.

CRISPR/Cas9-Mediated Multiplex Genome Editing of the BnWRKY11 and BnWRKY70 Genes in Brassica napus L.

Targeted genome editing is a desirable means of basic science and crop improvement. The clustered, regularly interspaced, palindromic repeat (CRISPR)/Cas9 (CRISPR-associated 9) system is currently the simplest and most commonly used system in targeted genomic editing in plants. Single and multiplex genome editing in plants can be achieved under this system. In Arabidopsis, AtWRKY11 and AtWRKY70 genes were involved in JA- and SA-induced resistance to pathogens, in rapeseed (Brassica napus L.), BnWRKY11 and BnWRKY70 genes were found to be differently expressed after inoculated with the pathogenic fungus, Sclerotinia sclerotiorum (Lib.) de Bary. In this study, two Cas9/sgRNA constructs targeting two copies of BnWRKY11 and four copies of BnWRKY70 were designed to generate BnWRKY11 and BnWRKY70 mutants respectively. As a result, twenty-two BnWRKY11 and eight BnWRKY70 independent transformants (T0) were obtained, with the mutation ratios of 54.5% (12/22) and 50% (4/8) in BnWRKY11 and BnWRKY70 transformants respectively. Eight and two plants with two copies of mutated BnWRKY11 and BnWRKY70 were obtained respectively. In T1 generation of each plant examined, new mutations on target genes were detected with high efficiency. The vast majority of BnWRKY70 mutants showed editing in three copies of BnWRKY70 in examined T1 plants. BnWRKY70 mutants exhibited enhanced resistance to Sclerotinia, while BnWRKY11 mutants showed no significant difference in Sclerotinia resistance when compared to non-transgenic plants. In addition, plants that overexpressed BnWRKY70 showed increased sensitivity when compared to non-transgenic plants. Altogether, our results demonstrated that BnWRKY70 may function as a regulating factor to negatively control the Sclerotinia resistance and CRISPR/Cas9 system could be used to generate germplasm in B. napus with high resistance against Sclerotinia.

iTRAQ-Based Comparative Proteomic Analysis of the Roots of TWO Winter Turnip Rapes (Brassica rapa L.) with Different Freezing-Tolerance.

The freezing tolerance of roots is crucial for winter turnip rape (Brassica rapa L.) survival in the winter in Northwest China. Cold acclimation (CA) can alleviate the root damage caused by freezing stress. To acknowledge the molecular mechanisms of freezing tolerance in winter turnip rape, two Brassica rapa genotypes, freezing stressed after the induction of cold acclimation, were used to compare the proteomic profiles of roots by isobaric tags for relative and absolute quantification (iTRAQ). Under freezing stress (-4 °C) for 8 h, 139 and 96 differentially abundant proteins (DAPs) were identified in the roots of "Longyou7" (freezing-tolerant) and "Tianyou4" (freezing-sensitive), respectively. Among these DAPs, 91 and 48 proteins were up- and down-accumulated in "Longyou7", respectively, and 46 and 50 proteins were up- and down-accumulated in "Tianyou4", respectively. Under freezing stress, 174 DAPs of two varieties were identified, including 9 proteins related to ribosome, 19 DAPs related to the biosynthesis of secondary metabolites (e.g., phenylpropanoid and the lignin pathway), and 22 down-accumulated DAPs enriched in oxidative phosphorylation, the pentose phosphate pathway, fructose and mannose metabolism, alpha-linolenic acid metabolism, carbon fixation in photosynthetic organisms, ascorbate and aldarate metabolism. The expressional pattern of the genes encoding the 15 significant DAPs were consistent with the iTRAQ data. This work indicates that protein biosynthesis, lignin synthesis, the reduction of energy consumption and a higher linolenic acid content contribute to the freezing tolerance of winter turnip rape. Functional analyses of these DAPs would be helpful in dissecting the molecular mechanisms of the stress responses in B. rapa.

Arabidopsis DELLA and JAZ proteins bind the WD-repeat/bHLH/MYB complex to modulate gibberellin and jasmonate signaling synergy.

Integration of diverse environmental and endogenous signals to coordinately regulate growth, development, and defense is essential for plants to survive in their natural habitat. The hormonal signals gibberellin (GA) and jasmonate (JA) antagonistically and synergistically regulate diverse aspects of plant growth, development, and defense. GA and JA synergistically induce initiation of trichomes, which assist seed dispersal and act as barriers to protect plants against insect attack, pathogen infection, excessive water loss, and UV irradiation. However, the molecular mechanism underlying such synergism between GA and JA signaling remains unclear. In this study, we revealed a mechanism for GA and JA signaling synergy and identified a signaling complex of the GA pathway in regulation of trichome initiation. Molecular, biochemical, and genetic evidence showed that the WD-repeat/bHLH/MYB complex acts as a direct target of DELLAs in the GA pathway and that both DELLAs and JAZs interacted with the WD-repeat/bHLH/MYB complex to mediate synergism between GA and JA signaling in regulating trichome development. GA and JA induce degradation of DELLAs and JASMONATE ZIM-domain proteins to coordinately activate the WD-repeat/bHLH/MYB complex and synergistically and mutually dependently induce trichome initiation. This study provides deep insights into the molecular mechanisms for integration of different hormonal signals to synergistically regulate plant development.

Interaction between MYC2 and ETHYLENE INSENSITIVE3 modulates antagonism between jasmonate and ethylene signaling in Arabidopsis.

Plants have evolved sophisticated mechanisms for integration of endogenous and exogenous signals to adapt to the changing environment. Both the phytohormones jasmonate (JA) and ethylene (ET) regulate plant growth, development, and defense. In addition to synergistic regulation of root hair development and resistance to necrotrophic fungi, JA and ET act antagonistically to regulate gene expression, apical hook curvature, and plant defense against insect attack. However, the molecular mechanism for such antagonism between JA and ET signaling remains unclear. Here, we demonstrate that interaction between the JA-activated transcription factor MYC2 and the ET-stabilized transcription factor ETHYLENE-INSENSITIVE3 (EIN3) modulates JA and ET signaling antagonism in Arabidopsis thaliana. MYC2 interacts with EIN3 to attenuate the transcriptional activity of EIN3 and repress ET-enhanced apical hook curvature. Conversely, EIN3 interacts with and represses MYC2 to inhibit JA-induced expression of wound-responsive genes and herbivory-inducible genes and to attenuate JA-regulated plant defense against generalist herbivores. Coordinated regulation of plant responses in both antagonistic and synergistic manners would help plants adapt to fluctuating environments.

Targeting insulin-like growth factor-binding protein-3 by microRNA-125b promotes tumor invasion and poor outcomes in non-small-cell lung cancer.

Insulin-like growth factor-binding protein-3 acts as a tumor suppressor that inhibits the PI3K/AKT signaling pathway due to blocking insulin growth factor-1 binding to its receptor. We hypothesized that insulin-like growth factor-binding protein-3 might be targeted by microRNA-125b and promote tumor invasion and poor outcome in non-small-cell lung cancer via activation of the PI3K/AKT signaling pathway. Real-time polymerase chain reaction and immunohistochemistry were performed to determine the level of microRNA-125b, insulin-like growth factor-binding protein-3 messenger RNA, and phosphorylated-AKT expression in 105 tumors from non-small-cell lung cancer patients. Low insulin-like growth factor-binding protein-3 messenger RNA levels and positive phosphorylated-AKT expression were more commonly found in patients with high microRNA-125b tumors than low microRNA-125b tumors. A poorer overall survival and relapse-free survival were observed in patients with high microRNA-125b tumors than low-microRNA-125b tumors in p53-mutated patients, but not in p53-wild-type patients. Mechanistically, microRNA-125b promotes invasion ability in p53-mutated cells via the PI3K/AKT activation by targeting of insulin-like growth factor-binding protein-3, but this effect was not observed in p53-wild-type cells. An increase in phosphorylated-AKT expression due to targeting of insulin-like growth factor-binding protein-3 by microRNA-125b was responsible for cell invasion in p53-mutated cells. In conclusion, the microRNA-125b level promotes invasive ability in p53-mutated cells via PI3K/AKT activation by targeting of insulin-like growth factor-binding protein-3, thereby resulting in p53-mutated non-small-cell lung cancer patients with poor outcomes.

The bHLH subgroup IIId factors negatively regulate jasmonate-mediated plant defense and development.

Plants have evolved sophisticated systems for adaptation to their natural habitat. In response to developmental and environmental cues, plants produce and perceive jasmonate (JA) signals, which induce degradation of JASMONATE-ZIM-Domain (JAZ) proteins and derepress the JAZ-repressed transcription factors to regulate diverse aspects of defense responses and developmental processes. Here, we identified the bHLH subgroup IIId transcription factors (bHLH3, bHLH13, bHLH14 and bHLH17) as novel targets of JAZs. These bHLH subgroup IIId transcription factors act as transcription repressors and function redundantly to negatively regulate JA responses. The quadruple mutant bhlh3 bhlh13 bhlh14 bhlh17 showed severe sensitivity to JA-inhibited root growth and JA-induced anthocyanin accumulation, and exhibited obvious increase in JA-regulated plant defense against pathogen infection and insect attack. Transgenic plants overexpressing bHLH13 or bHLH17 displayed reduced JA responses. Furthermore, these bHLH factors functioned as transcription repressors to antagonize the transcription activators, such as MYC2 and the WD-repeat/bHLH/MYB complex, through binding to their target sequences. Coordinated regulation of JA responses by transcription activators and repressors would benefit plants by allowing fine regulation of defense and development, and survival in their frequently changing environment.

[Related factors of optical coherence tomography detected in-stent heterogonous neointima].

OBJECTIVE: To explore the related factors of optical coherence tomography (OCT) detected in-stent heterogeneous neointimal in coronary stents. METHODS: A total of 143 cases of coronary heart disease patients with OCT detected in-stent neointimal hyperplasia in Fuwai hospital from September 2009 to April 2012 were included in this study and patients data were retrospectively analyzed. Patients were divided into heterogeneous intima group(26 cases) and homogeneous intima group(117 cases)according to neointimal characteristics. Clinical features and OCT characteristics of the 2 groups were compared and binary logistic regression analysis was performed to analyze the risk factors of in-stent heterogonous neointimal hyperplasia. RESULTS: Compared to homogeneous intima group, patients in heterogeneous intima group had significantly higher cholesterol level ((5.31±1.11)mmol/L vs.(4.70±0.94)mmol/L, P=0.005), low-density lipoprotein cholesterol level ((2.57±0.87)mmol/L vs.(2.29±0.46)mmol/L, P=0.021) and triglyceride level (2.12(1.82-2.87)mmol/L vs. 1.90(1.73-2.11)mmol/L, P=0.015). Moreover, the percent of percutaneous coronary intervention (PCI) because of acute coronary syndrome (23.1%(6/26) vs. 6.8%(8/117), P=0.022) and the thin cap neoatheroma (5.8%(28/481)vs. 3.9%(89/2 276), P=0.043) were also significantly higher in heterogeneous intima group than in homogeneous intima group. Binary logistic regression analysis showed that low-density lipoprotein cholesterol (OR=2.74, 95%CI 1.04-7.24, P=0.042), triglyceride (OR=2.88, 95%CI 1.05-7.89, P=0.040), PCI for acute coronary syndrome (OR=12.74, 95%CI 2.69-60.49, P=0.001), and cerebrovascular disease (OR=13.09, 95%CI 2.16-79.53, P=0.005) were risk factors for in-stent heterogenous intima. Time post stent implantation was protective factor for in-stent heterogenous intima (OR=0.63, 95%CI 0.42-0.96, P=0.033). CONCLUSION: OCT detected heterogeneous intima is correlated with level of blood lipid, PCI for acute coronary syndrome and history of cerebrovascular disease, and it may lead to unstable intima.

Paxillin promotes tumor progression and predicts survival and relapse in oral cavity squamous cell carcinoma by microRNA-218 targeting.

High-risk human papillomavirus (HPV) 16-infected oral cavity squamous cell carcinoma (OCSCC) differs significantly from non-HPV-infected OCSCC. However, the molecular pathogenesis of HPV-infected OCSCC remains unclear. Paxillin (PXN) has been reported to promote lung tumor progression by miR-218 targeting. In addition, expression of miR-218 has been shown to be reduced by HPV16 E6 in cervical cancer. We thus asked whether PXN can promote tumor progression by E6-reduced miR-218 in OCSCC, especially in HPV-infected OCSCC. Mechanistic studies demonstrated that PXN expression increased markedly upon E6-mediated reductions in miR-218, resulting in increased colony formation and invasion capabilities in HPV-infected OCSCC cells. Among tumor specimens, HPV16/18 infection was negatively associated with miR-218 expression and positively associated with PXN expression. Kaplan-Meier and Cox regression models demonstrated that patients with low-miR-218 tumors or high-PXN tumors exhibited shorter overall survival (OS) and relapse-free survival (RFS) than those with high-miR-218 tumors or low-PXN tumors. Interestingly, HPV-infected patients with low-miR-218, high-PXN tumors and both combinations exhibited the worst OS and RFS compared with patients in their counterparts. These observations in patients were consistent with the findings from the cell model. Therefore, we suggest that PXN might be targeted to suppress tumor progression and consequently to improve outcomes in OCSCC, especially in HPV-infected OCSCC.

MicroRNA-21 promotes tumour malignancy via increased nuclear translocation of ß-catenin and predicts poor outcome in APC-mutated but not in APC-wild-type colorectal cancer.

MiR-21 has been associated with poor prognosis in colon adenocarcinomas. However, in our preliminary data, the prognostic value of miR-21 levels was observed only in adenomatous polyposis coli (APC)-mutated tumours, not in APC-wild-type tumours. We explored whether ß-catenin nuclear translocation was synergistically promoted by miR-21 in APC-mutated cells but not in APC-wild-type cells. We enrolled 165 colorectal tumour to determine APC mutation, miR-21 levels and nuclear ß-catenin expression by direct sequencing, real-time PCR and immunohistochemistry. Overall survival and relapse-free survival were analysed by Kaplan-Meier and Cox regression models. The mechanistic action of ß-catenin nuclear translocation modulated by miR-21 and its effect on cell invasion were evaluated in a cell model. Positive nuclear ß-catenin expression was more commonly occurred in APC-mutated tumours than in APC-wild-type tumours. High miR-21 levels were relatively more common in tumours with positive nuclear ß-catenin expression than in those with negative nuclear ß-catenin expression. APC-mutated tumours with high miR-21 levels had shorter overall survival and relapse-free survival periods compared with others. However, the prognostic value of miR-21 levels was not observed in APC-wild-type tumours. Phosphorylation of ß-catenin at Ser552 via the miR-21-mediated PTEN/AKT axis plays a critical role in ß-catenin nuclear translocation in APC-mutated cells but not in APC-wild-type cells. Moreover, nuclear ß-catenin expression increased by miR-21 is responsible for the capability of invasiveness. In summary, nuclear translocation of ß-catenin increased by miR-21 promotes tumour malignancy and a poor outcome in APC-mutated patients but not in APC-wild-type colorectal cancer.

The Jasmonate-ZIM-domain proteins interact with the WD-Repeat/bHLH/MYB complexes to regulate Jasmonate-mediated anthocyanin accumulation and trichome initiation in Arabidopsis thaliana.

Jasmonates (JAs) mediate plant responses to insect attack, wounding, pathogen infection, stress, and UV damage and regulate plant fertility, anthocyanin accumulation, trichome formation, and many other plant developmental processes. Arabidopsis thaliana Jasmonate ZIM-domain (JAZ) proteins, substrates of the CORONATINE INSENSITIVE1 (COI1)-based SCF(COI1) complex, negatively regulate these plant responses. Little is known about the molecular mechanism for JA regulation of anthocyanin accumulation and trichome initiation. In this study, we revealed that JAZ proteins interact with bHLH (Transparent Testa8, Glabra3 [GL3], and Enhancer of Glabra3 [EGL3]) and R2R3 MYB transcription factors (MYB75 and Glabra1), essential components of WD-repeat/bHLH/MYB transcriptional complexes, to repress JA-regulated anthocyanin accumulation and trichome initiation. Genetic and physiological evidence showed that JA regulates WD-repeat/bHLH/MYB complex-mediated anthocyanin accumulation and trichome initiation in a COI1-dependent manner. Overexpression of the MYB transcription factor MYB75 and bHLH factors (GL3 and EGL3) restored anthocyanin accumulation and trichome initiation in the coi1 mutant, respectively. We speculate that the JA-induced degradation of JAZ proteins abolishes the interactions of JAZ proteins with bHLH and MYB factors, allowing the transcriptional function of WD-repeat/bHLH/MYB complexes, which subsequently activate respective downstream signal cascades to modulate anthocyanin accumulation and trichome initiation.

The Jasmonate-ZIM domain proteins interact with the R2R3-MYB transcription factors MYB21 and MYB24 to affect Jasmonate-regulated stamen development in Arabidopsis.

The Arabidopsis thaliana F-box protein CORONATINE INSENSITIVE1 (COI1) perceives jasmonate (JA) signals and subsequently targets the Jasmonate-ZIM domain proteins (JAZs) for degradation by the SCF(COI1)-26S proteasome pathway to mediate various jasmonate-regulated processes, including fertility, root growth, anthocyanin accumulation, senescence, and defense. In this study, we screened JAZ-interacting proteins from an Arabidopsis cDNA library in the yeast two-hybrid system. MYB21 and MYB24, two R2R3-MYB transcription factors, were found to interact with JAZ1, JAZ8, and JAZ11 in yeast and in planta. Genetic and physiological experiments showed that the myb21 myb24 double mutant exhibited defects specifically in pollen maturation, anther dehiscence, and filament elongation leading to male sterility. Transgenic expression of MYB21 in the coi1-1 mutant was able to rescue male fertility partially but unable to recover JA-regulated root growth inhibition, anthocyanin accumulation, and plant defense. These results demonstrate that the R2R3-MYB transcription factors MYB21 and MYB24 function as direct targets of JAZs to regulate male fertility specifically. We speculate that JAZs interact with MYB21 and MYB24 to attenuate their transcriptional function; upon perception of JA signal, COI1 recruits JAZs to the SCF(COI1) complex for ubiquitination and degradation through the 26S proteasome; MYB21 and MYB24 are then released to activate expression of various genes essential for JA-regulated anther development and filament elongation.