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Epstein-Barr virus (EBV) is a human cancer-related virus closely associated with lymphoid and epithelial malignancies, and EBV glycoprotein B (gB) plays an essential role in viral entry into both B cells and epithelial cells by promoting cell-cell fusion. EBV gB is exclusively modified with high-mannose-linked N-glycans and primarily localizes to the endoplasmic reticulum (ER) with low levels on the plasma membrane (PM). However, the mechanism through which gB is regulated within host cells is largely unknown. Here, we report the identification of F-box only protein 2 (FBXO2), an SCF ubiquitin ligase substrate adaptor that preferentially binds high-mannose glycans and attenuates EBV infectivity by targeting N-glycosylated gB for degradation. gB possesses seven N-glycosylation sites, and FBXO2 directly binds to these high-mannose moieties through its sugar-binding domain. The interaction promotes the degradation of glycosylated gB via the ubiquitin-proteasome pathway. Depletion of FBXO2 not only stabilizes gB but also promotes its transport from the ER to the PM, resulting in enhanced membrane fusion and viral entry. FBXO2 is expressed in epithelial cells but not B cells, and EBV infection up-regulates FBXO2 levels. In summary, our findings highlight the significance of high-mannose modification of gB and reveal a novel host defense mechanism involving glycoprotein homeostasis regulation. [ABSTRACT FROM AUTHOR]

Histone modifications are involved in regulation of chromatin structure. To investigate the relationship between chromatin modification and cell cycle regulation during plant cell proliferation, Okadaic acid (OA), a specific inhibitor of serine/threonine protein phosphatase, was applied in this study. The results showed that OA caused the cell cycle arrest at preprophase, leading to seedling growth inhibition. Western blotting assay revealed that the spatial distribution of phosphorylation of Ser10 histone H3 tails (H3S10ph) signals was altered under OA treatment. Reactive oxygen species (ROS) was found to be at higher levels and TdT-mediated dUTP nick end labeling (TUNEL) assay displayed DNA breaks happened at the chromatin after treatment with OA, companied with an increase in the acetylation of histone H4 at lysine 5 (H4K5ac) level. From these observations, we speculated that the alteration of the spatial distribution of H3S10ph and the level of H4K5ac was involved in the procedure that OA induced DNA breaks and G2-M arrested by the accumulation of ROS, and that the histone H3S10ph and H4K5ac might facilitate DNA repair by their association with the chromatin decondensation. [ABSTRACT FROM AUTHOR]

We conducted a meta-analysis to explore the relationships between p14ARF gene methylation and clinicopathological features of colorectal cancer (CRC). Databases, including Pubmed, Embase and Cochrane Library, were searched and, finally, a total of 18 eligible researches encompassing 1988 CRC patients were selected. Combined odds ratios (ORs) with 95% confidence intervals (95% CIs) were evaluated under a fixed effects model for absence of heterogeneity. Significant associations were observed between p14ARF gene methylation and tumor location (OR = 2.35, 95% CI: 1.55–3.55, P = 0.001), microsatellite instability (MSI) status (OR = 3.28, 95% CI: 2.12–5.07, P<0.0001). However, there were no significant associations between p14ARF gene methylation and tumor stage, tumor differentiation. We concluded that p14ARF gene methylation may be significantly associated with tumor location, and MSI status of CRC. [ABSTRACT FROM AUTHOR]

Phosphate (Pi) transporters play critical roles in Pi acquisition and homeostasis. However, little is known about these transporters in oilseed rape. Therefore, the aim of the present study was to characterize the members of the PHT1 gene family in allotetraploid Brassica napus and to analyze their expression profiles in response to environmental stresses. In total, 49 PHT1 family members were identified in B. napus, including 27 genes in the A subgenome and 22 in the C subgenome. Most of the PHT1 proteins were predicted to localize to the plasma membrane. Phylogenetic analysis suggested that the members of the PHT1 gene family can be divided into seven clades, with the introns/exons and protein motifs conserved in each clade. Collinearity analysis revealed that most of the BnaPHT1 genes shared syntenic relationships with PHT1 members in Arabidopsis thaliana, B. rapa, and B. oleracea, and that whole-genome duplication (polyploidy) played a major driving force for BnaPHT1 evolution in addition to segmental duplication. Transcript abundance analysis showed that a broad range of expression patterns of individual BnaPHT1 genes occurred in response to phosphorus (P) deficiency. In addition, the expression levels of BnaPHT1 genes can be regulated by different nutrient stresses, including nitrogen (N), potassium (K), sulfur (S) and iron (Fe) stresses. Moveover, salt and drought stresses can regulate the transcript abundances of BnaPHT1s, as well as phytohormones including auxin and cytokinin. Gene coexpression analysis based on the RNA-seq data implied that BnaPHT1s might cooperate with each other as well as with other genes to regulate nutrient homeostasis in B. napus. Further analysis of the promoters revealed that GT-1, DRE and P1BS elements are widely distributed within the promoter regions of BnaPHT1 genes. Our results indicate that BnaPHT1s might be involved in cross-talk for sensing the external status of P, N, K, S and Fe, as well as salt and drought stresses. Moreover, these processes might be mediated by phytohormones. Our findings provide the first step in the complex genetic dissection of the Pi transport system in plants and implicate multiple transcriptional regulation, which probably refers to new roles of PHT1 genes in B. napus. [ABSTRACT FROM AUTHOR]

The Gram-negative pathogen, Acinetobacter baumannii has emerged as a global nosocomial health threat affecting the majority of hospitals in the U.S. and abroad. The redox protein thioredoxin has been shown to play several roles in modulation of cellular functions affecting various virulence factors in Gram-negative pathogens. This study aims to explore the role of thioredoxin-A protein (TrxA) in A. baumannii virulence. We determined that deletion of the TrxA gene did not significantly affect resistance to environmental stressors such as temperature, salt, and pH. However, TrxA was critical for survival in the presence of elevated levels of hydrogen peroxide. Lack of TrxA was associated with decreased expression of type IV pili related genes and an inability to undergo normal twitching motility. Interestingly, the TrxA-null mutant was able to form biofilms better than the wildtype (WT) and was observed to be significantly less virulent than the WT in a pulmonary infection model. These results are supportive of thioredoxin playing a key role in A. baumannii virulence. [ABSTRACT FROM AUTHOR]

Phytolacca americana L. (pokeweed) has metal phytoremediation potential, but little is known about its metal accumulation-related genes. In this study, the de novo sequencing of total RNA produced 53.15 million reads covering 10.63 gigabases of transcriptome raw data in cadmium (Cd)-treated and untreated pokeweed. Of the 97,502 assembled unigenes, 42,197 had significant matches in a public database and were annotated accordingly. An expression level comparison between the samples revealed 1515 differentially expressed genes (DEGs), 923 down- and 592 up-regulated under Cd treatment. A KEGG pathway enrichment analysis of DEGs revealed that they were involved in 72 metabolism pathways, with photosynthesis, phenylalanine metabolism, ribosome, phenylpropanoid biosynthesis, flavonoid biosynthesis and carbon fixation in photosynthetic organisms containing 24, 18, 72, 14, 7 and 15 genes, respectively. Genes related to heavy metal tolerance, absorption, transport and accumulation were also identified, including 11 expansins, 8 nicotianamine synthases, 6 aquaporins, 4 ZRT/IRT-like proteins, 3 ABC transporters and 3 metallothioneins. The gene expression results of 12 randomly selected DEGs were validated using quantitative real-time PCR, and showed different response patterns to Cd in their roots, stems and leaves. These results may be helpful in increasing our understanding of heavy metal hyperaccumulators and in future phytoremediation applications. [ABSTRACT FROM AUTHOR]

Using the phoA-fusion technology, the recombinant metallothionein (MT) from freshwater crab (Sinopotamon yangtsekiense) has been successfully produced in Escherichia coli. MT purified from the bacterial suspension showed one polypeptide with a molecular weight of 7 kDa by tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis (Tricine-SDS-PAGE). Western-blotting confirmed the polypeptides had a specific reactivity with mouse polyclonal MT anti-serum. Based on the purified MT and MT anti-serum, the reaction parameters for an enzyme-linked immunosorbent assay (ELISA) were developed. The direct coating ELISA showed a higher linear relationship compared to antibody sandwich coating ELISA. The optimal dilution rates of purified MT anti-serum and coating period were shown to be 1:160,000 and 12 hours at 4°C. At 37°C, the appropriate reaction duration of the first antibody and the second antibody were 2 hours and 1 hour, respectively. According to these optimal parameters, the standard linear equation, y = 0.0032x + 0.1769 (R2 = 0.9779, x, y representing MT concentration and OD450 value), was established for the determination of MT concentration with a valid range of 3.9–500 ng/ml. In verification experiments, the mean coefficients of variation of the intra-assay and inter-assay were 3.260% and 3.736%, respectively. According to the result of MT recovery, ELISA with an approaching 100% MT recovery was more reliable and sensitive than the Cd saturation assay. In conclusion, the newly developed ELISA of this study was precise, stable and repeatable, and could be used as a biomarker tool to monitor pollution by heavy metals. [ABSTRACT FROM AUTHOR]

Aims: To investigate if nuclear NF-κB p65 expression in ex vivo isolated peripheral blood mononuclear cells correlates with urinary MCP-1 or RANTES and the severity of type 2 diabetic nephropathy. Methods: According to their urinary albumin-to-creatinine ratio (uACR), 107 patients with type 2 diabetes (eGFR >60 ml/min) were divided into normal albuminuria group (DN0 group, 38 cases), microalbuminuria group (DN1 group, 38 cases), and macroalbuminuria group (DN2 group, 31 cases), compared with matched healthy normal control group (NC group, 30 cases). Nuclear NF-κB p65 protein expression levels in peripheral blood mononuclear cells were detected by western blotting. Real-time quantitative polymerase chain reaction was used to detect NF-κB p65 mRNA expression and ELISA assay was used to detect the levels of urinary MCP-1 and RANTES. Results: Nuclear NF-κB p65 protein and NF-κB p65 mRNA expression levels in peripheral blood mononuclear cells, urinary MCP-1/Cr and RANTES/Cr were all significantly higher in all diabetes groups as compared with NC group. In particular, the increase of nuclear NF-κB p65 protein and NF-κB p65 mRNA expressions, urinary MCP-1/Cr and RANTES/Cr all correlated with the severity of type 2 diabetic nephropathy as indicated by the increase in uACR. Pearson correlation analysis indicated that both urinary MCP-1/Cr and RANTES/Cr were positively correlated with nuclear NF-κB p65 protein or NF-κB p65 mRNA levels. Stepwise multiple regression analysis showed that nuclear NF-κB p65 protein or NF-κB p65 mRNA was an independent variable for urinary MCP-1/Cr, and MCP-1/Cr and RANTES/Cr were two independent variables for uACR. Conclusion: Our research demonstrates that nuclear NF-κB p65 protein and mRNA expressions in ex vivo isolated peripheral blood mononuclear cells well correlate with urinary MCP-1/Cr, RANTES/Cr and the severity of type 2 diabetic nephropathy. [ABSTRACT FROM AUTHOR]

It has been widely recognized that the early or delayed puberty appears to display harmful effects on adult health outcomes. During the timing of puberty, pituitaries responds to the hypothalamus and then introduce the following response of ovaries in hypothalamic-pituitary-gonadal axis. DNA methylation has been recently suggested to regulate the onset of puberty in female mammals. However, to date, the changes of DNA methylation in pituitaries have not been investigated during pubertal transition. In this study, using gilts as the pubertal model, the genome-scale DNA methylation of pituitaries was profiled and compared across Pre-, In- and Post-puberty by using the reduced representation bisulfite sequencing. We found that average methylation levels of each genomic feature in Post- were lower than Pre- and In-pubertal stage in CpG context, but they were higher in In- than that in Pre- and Post-pubertal stage in CpH (where H = A, T, or C) context. The methylation patterns of CpHs were more dynamic than that of CpGs at the location of high CpG content, low CpG content promoter genes, and differently genomic CGIs. Furthermore, the differently genomic CGIs were likely to show in a similar manner in CpG context but display in a stage-specific manner in the CpH context across the Pre-, In- and Post-pubertal stage. Among these pubertal stages, 5 kb upstream regions of the transcription start sites were protected from both CpG and CpH methylation changes. 12.65% of detected CpGs were identified as the differentially methylated CpGs, regarding 4301 genes which were involved in the fundamental functions of pituitaries. 0.35% of detected CpHs were identified as differentially methylated CpHs, regarding 3691 genes which were involved in the biological functions of releasing gonadotropin hormones. These observations and analyses would provide valuable insights into epigenetic mechanism of the initiation of puberty in pituitary level. [ABSTRACT FROM AUTHOR]

In recent years, an increasing number of studies have reported the presence of plant miRNAs in human samples, which resulted in a hypothesis asserting the existence of plant-derived exogenous microRNA (xenomiR). However, this hypothesis is not widely accepted in the scientific community due to possible sample contamination and the small sample size with lack of rigorous statistical analysis. This study provides a systematic statistical test that can validate (or invalidate) the plant-derived xenomiR hypothesis by analyzing 388 small RNA sequencing data from human samples in 11 types of body fluids/tissues. A total of 166 types of plant miRNAs were found in at least one human sample, of which 14 plant miRNAs represented more than 80% of the total plant miRNA abundance in human samples. Plant miRNA profiles were characterized to be tissue-specific in different human samples. Meanwhile, the plant miRNAs identified from microbiome have an insignificant abundance compared to those from humans, while plant miRNA profiles in human samples were significantly different from those in plants, suggesting that sample contamination is an unlikely reason for all the plant miRNAs detected in human samples. This study also provides a set of testable synthetic miRNAs with isotopes that can be detected in situ after being fed to animals. [ABSTRACT FROM AUTHOR]

The Yangtze River Delta White Goat is the only goat breed that produces high-quality brush hair, or type III hair, which is specialized for use in top-grade writing brushes. There has been little research, especially molecular research, on the traits that result in high-quality brush hair in the Yangtze River Delta White Goat. To explore the molecular mechanisms of the formation of high-quality brush hair, High-throughput RNA-Seq technology was used to compare skin samples from Yangtze River Delta White Goats that produce high-quality hair and non high-quality hair for identification of the important genes and related pathways that might influence the hair quality traits. The results showed that 295 genes were expressed differentially between the goats with higher and lower hair quality, respectively. Of those genes, 132 were up-regulated, 62 were down-regulated, and 101 were expressed exclusively in the goats with high-quality brush hair. Gene Ontology and Metabolic Pathway Significant Enrichment analyses of the differentially expressed genes indicated that the MAP3K1, DUSP1, DUSP6 and the MAPK signaling pathway might play important roles in the traits important for high-quality brush hair. [ABSTRACT FROM AUTHOR]

The ribosomal RNA (rRNA) gene encodes rRNA for protein synthesis. Aberrant expression of the rRNA gene has been generally observed in tumor cells and levels of its promoter methylation as an epigenetic regulator affect rRNA gene transcription. The possible relationship between expression and promoter methylation of rDNA has not been examined in human clinical cervical cancer. Here we investigate rRNA gene expression by quantitative real time PCR, and promoter methylation levels by HpaII/MspI digestion and sodium bisulfite sequencing in the development of human cervical cancer. We find that indeed rRNA levels are elevated in most of cervical intraepithelial neoplasia (CIN) specimens as compared with non-cancer tissues. The rDNA promoter region in cervical intraepithelial neoplasia (CIN) tissues reveals significant hypomethylation at cytosines in the context of CpG dinucleotides, accompanied with rDNA chromatin decondensation. Furthermore treatment of HeLa cells with the methylation inhibitor drug 5-aza-2’-deoxycytidine (DAC) demonstrates the negative correlation between the expression of 45S rDNA and the methylation level in the rDNA promoter region. These data suggest that a decrease in rDNA promoter methylation levels can result in an increase of rRNA synthesis in the development of human cervical cancer. [ABSTRACT FROM AUTHOR]