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

MicroRNAs (miRNAs) play a critical role in the development of cancers. However, the role of miRNAs in glioma is still poorly understood. In this study, we demonstrate that microRNA-10a (miR-10a) promotes cell migration and invasion by negatively regulating the expression of Eph tyrosine kinase receptor A8 ( EphA8 ). Ectopic expression of EphA8 counteracts the promotion of migration and invasion induced by miR-10a. We further demonstrate that miR-10a and EphA8 regulate epithelial–mesenchymal transition (EMT) to affect cell migration and invasion. Collectively, we unveil a branch of the miR-10a/ EphA8 pathway that regulates the progression of glioma. [ABSTRACT FROM AUTHOR]

Objectives To study E2F3a expression and its clinical significance in children with acute lymphoblastic leukemia ( ALL). Methods We quantified E2F3a expression at diagnosis in 148 children with ALL by real-time PCR. In the test cohort ( n = 48), receiver operating characteristic ( ROC) curve was used to find the best cut-off point to divide the patients into E2F3a low- and high-expression groups. The prognostic significance of E2F3a expression was investigated in the test cohort and confirmed in the validation cohort ( n = 100). The correlations of E2F3a expression with the clinical features and treatment outcome of these patients were analyzed. Results ROC curve analysis indicated that the best cut-off point of E2F3a expression was 0.3780. In the test cohort, leukemia-free survival ( LFS) and event-free survival ( EFS) of the low-expression group were lower than those of the high-expression group (log rank: P = 0.026 for both). This finding was verified in the validation cohort. LFS, EFS, and overall survival were also lower in the low-expression group than in the high-expression group (log rank, P = 0.015, 0.008, and 0.002 respectively). E2F3a low expression was correlated with the existence of BCR- ABL fusion. An algorithm composed of E2F3a expression and minimal residual disease ( MRD) could predict relapse or induction failure more precisely than current risk stratification. These results were still significant in the ALL patients without BCR- ABL fusion. Conclusions Low expression of E2F3a was associated with inferior prognosis in childhood ALL. An algorithm composed of E2F3a expression and MRD could predict relapse or induction failure more precisely than that of the current risk stratification. [ABSTRACT FROM AUTHOR]

To gain insight into the coordination of gene expression profiles under abscisic acid (ABA) and H2O2 applications, global changes in gene expression in response to ABA and H2O2 in Arabidopsis seedlings were investigated using GeneChip (Santa Clara, CA, USA) arrays. Among over 24 000 genes present in the arrays, 459 transcripts were found to be significantly increased, whereas another 221 decreased following H2O2 treatment compared with control. Similar to treatment with H2O2, ABA treatment elevated the transcription of 391 genes and repressed that of 322 genes. One hundred and forty-three upregulated genes and 75 downregulated genes were shared between the two treatments and these genes were mainly involved in metabolism, signal transduction, transcription, defense, and resistance. Only two genes, which encode an APETALA2/dehydration-responsive element binding protein (AP2/DREBP) family transcriptional factor and a late embryogenesis-abundant protein, were downregulated by H2O2, but upregulated by ABA. These results suggest that, similar to ABA, H2O2 plays a global role in gene transcription of Arabidopsis seedlings. The transcriptional responses induced by the application of exogenous ABA and H2O2 overlapped substantially. These two treatments regulated most of the downstream genes in a coordinated manner. (Managing editor: Li-Hui Zhao) [ABSTRACT FROM AUTHOR]

The selection of suitable reference genes (RGs) for data normalization is a crucial step for obtaining reliable results from gene expression analysis using the quantitative real‐time polymerase chain reaction (qRT‐PCR). Expression stability of eleven putative RGs (miR‐100‐5p, miR‐92a‐3p, miR‐998‐3p, miR‐279d‐3p, miR‐305‐5p, miR‐276a‐3p, miR‐275‐3p, miR‐9a‐5p, miR‐2a‐3p, U6 snRNA and 5S rRNA) was assessed by using a web‐based tool: RefFinder, which integrates four algorithms (Delta Ct, geNorm, NormFinder, and BestKeeper), and the best combination number of RGs was calculated by geNorm. Validation of selected RGs was performed by an expression analysis of let‐7‐5p under different experimental conditions. The best combinations of RGs were shown as follows: miR‐100‐5p + miR‐275‐3p for temperature treatment, miR‐100‐5p + miR‐305‐5p for adult tissues, miR‐276a‐3p + miR‐9a‐5p for genders, miR‐2a‐3p + miR‐276a‐3p for days after eclosion, U6 snRNA + miR‐9a‐5p + miR‐2a‐3p for developmental stages, and U6 snRNA + miR‐279d‐3p for all above conditions, and there was no one RG suitable for all experimental conditions. Incorrect RG selection affected the evaluation of let‐7‐5p abundance. Our findings demonstrate that an integrated approach of multiple algorithms is necessary to identify reliable, stable RGs for miRNA evaluation, and provide a basis for further studies on expression and function analysis of miRNAs and their target genes in Galeruca daurica, a new pest with great outbreaks in Inner Mongolia since 2009. [ABSTRACT FROM AUTHOR]

Mutations in the γ‐secretase complex have been well‐described in familial hidradenitis suppurativa (HS). No gene mutations have been identified in sporadic HS, which comprises 60%–70% of all HS cases. Obesity and smoking are risk factors for HS and are closely related to DNA methylation, an essential epigenetic phenomenon. Hence, we hypothesized that epigenetic modifications might be involved in sporadic HS. To investigate genes with aberrant methylation in sporadic HS cases and assess their expression in skin lesions and blood from patients with HS. Skin lesion samples and corresponding normal skin were obtained from three patients with HS and subjected to whole‐genome DNA methylation sequencing. Blood samples were collected from 20 patients with HS and 20 healthy controls (HCs). The HS mouse model was established by applying tamoxifen to NcstnΔKC mice. Target gene expression was analysed by immunohistochemistry, immunofluorescence, western blotting, enzyme‐linked immunosorbent assay (ELISA) and semiquantitative real‐time polymerase chain reaction (RT‐qPCR). Among 10 807 differentially methylated genes, we filtered 2101 genes with hypermethylated promoter regions, and following bioinformatics analyses, we focused on CXC chemokine ligand 16 (CXCL16). Subsequent functional experiments confirmed the downregulation of CXCL16 and its receptor, CXC chemokine receptor (CXCR) 6, in skin tissue from HS patients and NcstnΔKC mice. Serum CXCL16 concentrations were also significantly decreased in patients with HS. Our data revealed the downregulation of CXCL16 and CXCR6 in HS. [ABSTRACT FROM AUTHOR]

Background and Purpose: Proteasome inhibitors represent a novel class of anti-tumour agents that have clinical efficacy against haematological and solid cancers. The anti-apoptotic protein BAG3 is a member of the Bcl-2-associated athanogene family. We have previously shown that BAG3 is up-regulated after exposure to proteasome inhibitors and that inhibition of BAG3 sensitized cells to apoptosis induced by proteasome inhibition. However, the mechanisms by which proteasome inhibition induced BAG3 expression remained unclear and the present experiments were designed to elucidate these mechanisms.Experimental Approach: Effects of the proteasome inhibitor MG132 on activation of mitogenic signalling pathways were evaluated in kidney cancer cells (A498, Caki1, Caki2), with Western blotting. Specific inhibitors against individual mitogenic signalling pathways, real-time reverse transcription-polymerase chain reaction and luciferase reporter assays were used to investigate the roles of mitogenic signalling pathways in BAG3 induction after proteasome inhibition. Cell death was evaluated using Annexin V/propidium iodide staining and subsequent FACS.Key Results: MG132 activated several key mitogenic signalling pathways including extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK) activities. Induction of BAG3 by MG132 was inhibited by blocking JNK, but not ERK1/2 and p38 MAPK signalling pathways. In addition, SP600125 and dominant-negative JNK1 suppressed BAG3 promoter-driven reporter gene expression. Furthermore, activation of the JNK pathway induced BAG in kidney cancer cells after treatment with MG132.Conclusions and Implications: Our results suggested that the JNK pathway was associated with the protective response against proteasome inhibition, by mediating induction of BAG3. [ABSTRACT FROM AUTHOR]

Abstract: Long noncoding RNAs (lncRNAs) have gained extensive attention in recent years, however, their effects on ultraviolet (UV) radiation‐induced skin photodamage remain to be elucidated. In this study, we performed high‐throughput RNA sequencing and comprehensive bioinformatics analyses to characterize the transcriptome profiles including lncRNAs and mRNAs in UVB‐irradiated primary human dermal fibroblasts (HDFs) and to explore the roles of lncRNAs in photoaging. Quantitative reverse transcription–polymerase chain reaction amplification was performed to verify the differentially expressed genes. We subsequently found that knocking down of RP11‐670E13.6, an up‐regulated lncRNA in UVB‐irradiated HDFs, promoted a robust senescence phenotype, including increased numbers of the senescence‐associated β‐galactosidase‐positive cells, decreased cell proliferation, accumulation of cells in G0/G1 phase and a characteristic gene expression signature of senescent cells. In addition, Western blot analysis showed that knocking down of RP11‐670E13.6 activated the p16‐pRB senescence pathway independent of the p53‐p21 pathway. Therefore, we propose that RP11‐670E13.6 may delay cellular senescence in UVB damaged HDFs through the p16‐pRB pathway. [ABSTRACT FROM AUTHOR]

The aim of this study was to identify a microRNA (miRNA) expression signature for predicting HCC (hepatocellular carcinoma) survival. A total of 322 HCC patients in The Cancer Genome Atlas (TCGA) database were randomly divided into training and testing set. miRNAs, associated with survival time in the training set, were identified by using univariate Cox regression analysis. The risk score was formulated based on the expression levels of these miRNAs. Then the miRNA signature was validated in testing set through Kaplan-Meier analysis and log-rank test. hsa-miR-301a, hsa-miR-132, hsa-miR-212, hsa-miR-489, and hsa-miR-1468 were identified to formulate risk score in training set and used to calculate the risk score of each patients in testing set. About 161 patients in testing set were segregated into high- and low-risk group according to the median risk score. The survival time of high-risk group was significantly shorter (p = 0.0248) than low-risk group in testing test. The target genes of five miRNAs were significantly enriched in valine, leucine, and isoleucine degradation pathway and PPAR signaling pathway. hsa-miR-1468 had an up-regulated tendency in HCC tissues compared to adjacent tumor tissues. The expression of hsa-miR-301a, hsa-miR-132, hsa-miR-212, hsa-miR-489, and hsa-miR-1468, which might be potential biomarkers to evaluate HCC patients' prognosis. [ABSTRACT FROM AUTHOR]

Aims Dopamine and glutamate receptors are densely expressed in the nucleus accumbens ( NAc). Active interactions between these receptors contribute to the development of neuropsychiatric diseases, such as drug addiction and relapse. However, the molecular mechanisms underlying these interactions remain unclear. Methods This study established a mouse model of intermittent morphine-induced mouse behavioral sensitization model. Western blot and electrophysiological recording methods were performed to directly identify the affective components of morphine behavioral sensitization. Results Interval morphine administration could cause significant locomotor sensitization. Hyperlocomotion and behavioral locomotor sensitization were significantly suppressed when ifenprodil (5 mg/kg), a selective NR2B subunit-containing N-methyl- d-aspartate ( NMDA) receptor antagonist, or nafadotride (25 μg/kg), a dopamine D3 receptor (D3R)-preferring antagonist, was coadministered with morphine. Western blot analysis showed that morphine behavioral sensitization induced a region-specific increase in phosphorylation of NR2B ( pNR2B) and total levels of NR2B (NR2B) expression in the NAc. Systemically administered nafadotride attenuated behavioral locomotor sensitization induced by morphine and significantly reversed the overexpression of pNR2B and NR2B subunit-containing NMDA receptor in the NAc. NMDA receptor-mediated excitatory postsynaptic currents in the NAc were also significantly reduced by nafadotride. Conclusions These findings suggest that D3Rs are involved in morphine-induced behavioral locomotor sensitization in mice by regulating the NR2B subunits of NMDA receptors in the NAc. [ABSTRACT FROM AUTHOR]

SUMMARY Aims: Gentiopicroside (Gent) is one of the secoiridoid compound isolated from Gentiana lutea. This compound exhibits analgesic activities and inhibits the expression of GluN2B-containing N-methyl-D-aspartate (NMDA) receptors in the anterior cingulate cortex in mice. Nucleus accumbens (NAc) is a forebrain structure known for its role in drug addiction. However, little is known about the role of Gent on morphine dependence and synaptic transmission changes in the NAc. Methods: Conditioned place preference (CPP) test and behavioral sensitization of locomotor activity were used to investigate drug-seeking related behaviors. Brain slices containing NAc were prepared, and whole-cell patch-clamp recordings were performed to record the excitatory postsynaptic currents (EPSCs). Expression of proteins was detected by Western blot analysis. Results: Systemic administration of Gent attenuated the CPP effect induced by morphine, but had no effect on morphine-induced behavioral sensitization. Gent significantly reversed overexpression of GluN2B-containing NMDA receptors and dopamine D2 receptors in NAc during the first week of morphine withdrawal. However, the compound did not affect the overexpression of GluN2A-containing NMDA receptors, GluA1, and dopamine D1 receptors. Lastly, Gent significantly reduced NMDA receptors-mediated EPSCs in the NAc. Conclusion: Our study provides strong evidence that Gent inhibits morphine dependence through downregulation of GluN2B-containing NMDA receptors in the NAc. [ABSTRACT FROM AUTHOR]

Background and objective: The pathogenesis and molecular mechanism underlying asthma remain undetermined. The purpose of this study was to identify genes and pathways involved in the early airway response (EAR) phase of asthma by using serial analysis of gene expression (SAGE). Methods: Two SAGE tag libraries of lung tissues derived from a rat model of asthma and controls were generated. Bioinformatic analyses were carried out using the Database for Annotation, Visualization and Integrated Discovery Functional Annotation Tool, Gene Ontology (GO) Tree Machine and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Results: A total of 26 552 SAGE tags of asthmatic rat lung were obtained, of which 12 221 were unique tags. Of the unique tags, 55.5% were matched with known genes. By comparison of the two libraries, 186 differentially expressed tags ( P < 0.05) were identified, of which 103 were upregulated and 83 were downregulated. Using the bioinformatic tools these genes were classified into 23 functional groups, 15 KEGG pathways and 37 enriched GO categories. Conclusions: The bioinformatic analyses of gene distribution, enriched categories and the involvement of specific pathways in the SAGE libraries have provided information on regulatory networks of the EAR phase of asthma. Analyses of the regulated genes of interest may inform new hypotheses, increase our understanding of the disease and provide a foundation for future research. [ABSTRACT FROM AUTHOR]

MDM2 is an oncoprotein whose transforming potential is activated by overexpression. The expression level of MDM2 is negatively regulated by orphan receptor TR3 that mainly acts as a transcriptional factor to regulate gene expression. However, the underlying mechanism is largely unclear. Here, we present the first evidence that inhibition of TR3 on MDM2 is mediated by p53. We found that TR3 directly interacts with p53 but not MDM2, and such interaction is critical for TR3 to inhibit MDM2 expression. TR3 downregulates p53 transcriptional activity by blocking its acetylation, leading to a decrease on the transcription level of MDM2. Furthermore, TR3 binding to p53 obstructs its ubiquitination and degradation induced by MDM2, resulting in the MDM2 ubiquitination and degradation. In addition, TR3 could enhance p53-mediated apoptosis induced by UV irradiation. Taken together, our findings demonstrate that p53 mediates the suppression of TR3 on MDM2 at both transcriptional and post-transcriptional level and suggest TR3 as a potential target to develop new anticancer agents that restrict MDM2-induced tumor progression. [ABSTRACT FROM AUTHOR]