Search

Background and objectivesThe potential association between rosacea and a heightened prevalence of Helicobacter pylori (HP) infection has been previously suggested. However, existing studies offer inconsistent results. This systematic review and meta-analysis aimed to elucidate the relationship between rosacea and HP infection.MethodsWe conducted comprehensive searches of PubMed, Embase, and Web of Science databases to identify relevant observational studies for our investigation. We utilized the random-effects model to aggregate the data to address the potential influence of heterogeneity among the studies on the outcome.ResultsOur analysis incorporated twenty-five datasets from 23 case-control and cross-sectional studies, encompassing 51,054 rosacea patients and 4,709,074 controls without skin disease. The pooled results revealed a significantly higher prevalence of HP infection in individuals with rosacea compared to controls (odds ratio [OR]: 1.51, 95% confidence interval [CI]: 1.17-1.95, pConclusionRosacea may be significantly associated with a higher prevalence of HP infection. High-quality prospective studies with delicately controlled confounding factors are needed to determine if HP infection is a risk factor for rosacea.

Background and objectives: The potential association between rosacea and a heightened prevalence of Helicobacter pylori (HP) infection has been previously suggested. However, existing studies offer inconsistent results. This systematic review and meta-analysis aimed to elucidate the relationship between rosacea and HP infection. Methods: We conducted comprehensive searches of PubMed, Embase, and Web of Science databases to identify relevant observational studies for our investigation. We utilized the random-effects model to aggregate the data to address the potential influence of heterogeneity among the studies on the outcome. Results: Our analysis incorporated twenty-five datasets from 23 case-control and cross-sectional studies, encompassing 51,054 rosacea patients and 4,709,074 controls without skin disease. The pooled results revealed a significantly higher prevalence of HP infection in individuals with rosacea compared to controls (odds ratio [OR]: 1.51, 95% confidence interval [CI]: 1.17–1.95, p<0.001; I2 = 79%). Subgroup analysis indicated an increased prevalence of HP infection in rosacea studies that utilized one (OR: 1.72, 95% CI: 1.11–2.66, p = 0.02; I2 = 76%) or more tests for HP infection (OR: 2.26, 95% CI: 1.29–3.98, p = 0.005; I2 = 56%). However, this association was not observed in population-based studies that determined HP infection based on prescription records for HP eradication drugs (OR: 0.90, 95% CI: 0.76–1.07, p = 0.024; I2 = 54%). Conclusion: Rosacea may be significantly associated with a higher prevalence of HP infection. High-quality prospective studies with delicately controlled confounding factors are needed to determine if HP infection is a risk factor for rosacea. [ABSTRACT FROM AUTHOR]

Biogenesis of membrane proteins is controlled by the protein homeostasis (proteostasis) network. We have been focusing on protein quality control of γ-aminobutyric acid type A (GABAA) receptors, the major inhibitory neurotransmitter-gated ion channels in mammalian central nervous system. Proteostasis deficiency in GABAA receptors causes loss of their surface expression and thus function on the plasma membrane, leading to epilepsy and other neurological diseases. One well-characterized example is the A322D mutation in the α1 subunit that causes its extensive misfolding and expedited degradation in the endoplasmic reticulum (ER), resulting in autosomal dominant juvenile myoclonic epilepsy. We aimed to correct misfolding of the α1(A322D) subunits in the ER as an approach to restore their functional surface expression. Here, we showed that application of BIX, a specific, potent ER resident HSP70 family protein BiP activator, significantly increases the surface expression of the mutant receptors in human HEK293T cells and neuronal SH-SY5Y cells. BIX attenuates the degradation of α1(A322D) and enhances their forward trafficking and function. Furthermore, because BiP is one major target of the two unfolded protein response (UPR) pathways: ATF6 and IRE1, we continued to demonstrate that modest activations of the ATF6 pathway and IRE1 pathway genetically enhance the plasma membrane trafficking of the α1(A322D) protein in HEK293T cells. Our results underlie the potential of regulating the ER proteostasis network to correct loss-of-function protein conformational diseases.

Generic and disease-specific health-related quality of life (HRQoL) instruments may reflect different aspects of lives in patients with Parkinson's disease (PD) and thus be associated with different determinants. We used the same cluster of predictors for the generic and disease-specific HRQoL instruments to examine and compare the determinants of HRQoL.HRQoL was measured in 92 patients with PD by the 36-item Short-Form Health Survey (SF-36) and the 39-item Parkinson's Disease Questionnaire (PDQ-39). The predictors included demographic and disease characteristics, and motor and non-motor symptoms. Multiple regression analyses were used to identify HRQoL determinants.Depressive symptoms and motor difficulties of daily living were the first two significant determinants for both instruments. The other significant determinant for the SF-36 was fatigue and non-motor difficulties of daily living, and for the PDQ-39 was motor signs of PD.The results suggest the importance of the evaluation and intervention focused on depressive symptoms and motor difficulties of daily living in patients with PD. In addition, the SF-36 seems more related to non-motor symptoms, while the PDQ-39 appears more associated with motor symptoms. This information is important for understanding results from these two instruments and for choosing which to use.

The plant growth, phosphate acquisition, Cd translocation, phytochelatins (PCs) production and antioxidant parameters [superoxide dismutase (SOD), catalase (CAT), guaiacol peroxidase (POD), ascorbate peroxidase (APX), glutathione reductase (GR), glutathione (GSH), ascorbate (ASA) and malonaldehyde (MDA)] were investigated in Cd-hyperaccumulator Solanum photeinocarpum inoculated with Glomus versiforme BGC GD01C (Gv) in Cd-added soils (0, 5, 10, 20, 40 mg Cd kg-1 soil). Mycorrhizal colonization rates were generally high (from 77% to 94%), and hardly affected by Cd. Gv colonization significantly enhanced P acquisition, growth and total Cd uptakes in both shoots and roots of S. photeinocarpum at all Cd levels. Meanwhile, Gv symbiosis significantly increased Cd concentration in the roots, and decreased Cd concentration in the shoots at all Cd levels, which indicates that Gv could promote phytostabilization by enhancing Cd accumulation in the roots to inhibit its translocation to shoots and the "dilution effects" linked to an increase in plant dry matter yield and a reduced Cd partitioning to shoots. Moreover, the improvement of CAT, POD and APX activities in the leaves of mycorrhizal plants infers that Gv symbiosis helped S. photeinocarpum to relieve oxidative damage to biomolecules in Cd-contaminated soil. The evident decline of MDA content in the leaves of mycorrhizal plants indicates that Gv symbiosis evidently improved antioxidant activities, and the enhancement of PCs production in the leaves of mycorrhizal plants suggests that Gv-inoculated plant may be more efficient to relieve Cd phytotoxicity. Therefore, the possible mechanisms of Cd phytotoxicity alleviation by Gv can be concluded as the decline of Cd concentration in the shoots and the improvement of P acquisition, PCs production and activities of CAT, POD, APX in mycorrhizal plants.

To identify the features of Chinese genetic prion diseases.Suspected Creutzfeldt-Jakob disease (CJD) cases that were reported under CJD surveillance were diagnosed and subtyped using the diagnostic criteria issued by the WHO. The general information concerning the patient, their clinical, MRI and EEG data, and the results of CSF 14-3-3 and PRNP sequencing were carefully collected from the database of the national CJD surveillance program and analyzed using the SPSS 11.5 statistical software program.Since 2006, 69 patients were diagnosed with genetic prion diseases and as having 15 different mutations. The median age of the 69 patients at disease onset was 53.5 years, varying from 19 to 80 years. The majority of patients displaying clinical symptoms were in the 50-59 years of age. FFI, T188K gCJD and E200K were the three most common subtypes. The disease appeared in the family histories of 43.48% of the patients. The clinical manifestations varied considerably among the various diseases. Patients who carried mutations in the N-terminus displayed a younger age of onset, were CSF 14-3-3 negative, had a family history of the condition, and experienced a longer duration of the condition. The clinical courses of T188K were significantly shorter than those of FFI and E200K gCJD, while the symptoms in the FFI group appeared at a younger age and for a longer duration. Moreover, the time intervals between the initial neurologist visit to the final diagnosis were similar among patients with FFI, T188K gCJD, E200K gCJD and other diseases.The features of Chinese genetic prion diseases are different from those seen in Europe and other Asian countries.

Three genes, including EGFR (epidermal growth factor receptor), CALM3 (calmodulin 3, calcium-modulated protein 3) and SMARCD1 (SWI/SNF-related matrix-associated actin-dependent regulator of chromatin subfamily d member 1), play different roles in bone and/or fat metabolism in Caucasian women. In this population-based investigation of 870 unrelated postmenopausal Caucasian women, CALM3 polymorphisms were significantly associated with femoral neck bone mineral density (FNK BMD), hip BMD and spine BMD. Age and tobacco status also affected BMD levels and were therefore corrected for in our statistical analysis.EGFR, CALM3 and SMARCD1 play roles in bone and/or fat metabolism. However, the correlations between the polymorphisms of these three genes and body composition levels, including BMD, remain to be determined.A population-based investigation of 870 white women was conducted. Forty-four SNPs (single nucleotide polymorphisms) in EGFR, CALM3 and SMARCD1 were chosen by the software, including those of potential functional importance. The candidate SNPs were genotyped by the KASPar assay for an association analysis with body composition levels. The correlation analysis was assessed by the Pearson's product-moment correlation coefficient and Spearman rank-order correlation tests, and the family-wise error was corrected using the Wald test implemented in PLINK.The SNP rs12461917 in the 3'-flanking region of the CALM3 gene was significantly associated with FNK BMD (P = 0.001), hip BMD (P

AIMS: Regular exercise as an effective non-pharmacological antihypertensive therapy is beneficial for prevention and control of hypertension, but the central mechanisms are unclear. In this study, we hypothesized that chronic exercise training (ExT) delays the progression of hypertension and attenuates cardiac hypertrophy by up-regulating anti-inflammatory cytokines, reducing pro-inflammatory cytokines (PICs) and restoring the neurotransmitters balance in the hypothalamic paraventricular nucleus (PVN) in young spontaneously hypertensive rats (SHR). In addition, we also investigated the involvement of nuclear factor-κB (NF-κB) p65 and NAD(P)H oxidase in exercise-induced effects. METHODS AND RESULTS: Moderate-intensity ExT was administrated to young normotensive Wistar-Kyoto (WKY) and SHR rats for 16 weeks. SHR rats had a significant increase in mean arterial pressure and cardiac hypertrophy. SHR rats also had higher levels of glutamate, norepinephrine (NE), phosphorylated IKKβ, NF-κB p65 activity, NAD(P)H oxidase subunit gp91(phox), PICs and the monocyte chemokine protein-1 (MCP-1), and lower levels of gamma-aminobutyric acid (GABA) and interleukin-10 (IL-10) in the PVN. These SHR rats also exhibited higher renal sympathetic nerve activity (RSNA), and higher plasma levels of PICs, and lower plasma IL-10. However, ExT ameliorates all these changes in SHR rats. CONCLUSION: These findings suggest that there are the imbalances between excitatory and inhibitory neurotransmitters and between pro- and anti-inflammatory cytokines in the PVN of SHR rats, which at least partly contributing to sympathoexcitation, hypertension and cardiac hypertrophy; chronic exercise training attenuates hypertension and cardiac hypertrophy by restoring the balances between excitatory and inhibitory neurotransmitters and between pro- and anti-inflammatory cytokines in the PVN; NF-κB and oxidative stress in the PVN may be involved in these exercise-induced effects.

OBJECTIVE: We evaluated a variety of non-invasive physiological technologies and a series of test approaches for examination of aviator performances under conditions of mental workload in order to provide a standard real-time test for physiological and psychological pilot fatigue assessments. METHODS: Twenty-one male aviators were selected for a simulated flight in a hypobaric cabin with artificial altitude conditions of 2400 meter above sea level. The simulated flight lasted for 1.5 h, and was repeated for two times with an intervening 0.5 h rest period outside the hypobaric cabin. Subjective criteria (a fatigue assessment instrument [FAI]) and objective criteria (a standing-position balance test as well as a critical flicker fusion frequency (CFF) test) were used for fatigue evaluations. RESULTS: No significant change was observed in the FAI scores before and after the simulated flight, indicating that there was no subjective fatigue feeling among the participants. However, significant differences were observed in the standing-position balance and CFF tests among the subjects, suggesting that psychophysiological indexes can reflect mental changes caused by workload to a certain extent. The CFF test was the simplest and clearly indicated the occurrence of workload influences on pilot performances after a simulated flight. CONCLUSIONS: Results showed that the CFF test was the easiest way to detect workload caused mental changes after a simulated flight in a hypobaric cabin and reflected the psychophysiological state of aviators. We suggest that this test might be used as an effective routine method for evaluating the workload influences on mental conditions of aviators.

Knowledge of drug safety in the pediatric population of China is limited. This study was designed to evaluate ADRs in children reported to the spontaneous reporting system (SRS) of Shanghai in 2009.Crude ADR reports submitted to Shanghai SRS in 2009 for individuals aged from birth to 17 years (including 17 years) were included. Data were analyzed with respect to age, gender, category of ADR (System Organ Class [SOC]), the severity of reports and type of reporter.A male overrepresentation was observed regarding the total number of reports. The most frequently reported group of drugs were vaccines (42.15%). Skin rash and fever were the commonest symptoms reported in the total pediatric dataset. The proportion of children that suffered from a serious ADR was 2.16% and that for drug related deaths was 0.34%. And we found that the multiple drug exposure experienced a high proportion of serious ADRs compared with the single drug use (χ² = 15.99, P

It is increasingly recognized that intra-uterine growth restriction (IUGR) is associated with an increased risk of metabolic disorders in late life. Previous studies showed that mice exposed to LPS in late gestation induced fetal IUGR. The present study investigated the effects of maternal LPS exposure during pregnancy on metabolic phenotypes in female adult offspring. Pregnant mice were intraperitoneally injected with LPS (50 µg/kg) daily from gestational day (GD)15 to GD17. After lactation, female pups were fed with standard-chow diets (SD) or high-fat diets (HFD). Glucose tolerance test (GTT) and insulin tolerance test (ITT) were assessed 8 and 12 weeks after diet intervention. Hepatic triglyceride content was examined 12 weeks after diet intervention. As expected, maternal LPS exposure during pregnancy resulted in fetal IUGR. Although there was an increasing trend on fat mass in female offspring whose dams were exposed to LPS during pregnancy, maternal LPS exposure during pregnancy did not elevate the levels of fasting blood glucose and serum insulin and hepatic triglyceride content in female adult offspring. Moreover, maternal LPS exposure during pregnancy did not alter insulin sensitivity in adipose tissue and liver in female adult offspring. Further analysis showed that maternal LPS exposure during pregnancy did not exacerbate HFD-induced glucose tolerance and insulin resistance in female adult offspring. In addition, maternal LPS exposure during pregnancy did not aggravate HFD-induced elevation of hepatic triglyceride content in female adult offspring. In conclusion, LPS-induced IUGR does not alter metabolic phenotypes in adulthood.

The idea of retinal and ex-retinal sources of saccadic suppression has long been established in previous studies. However, how they are implemented in local circuit remains unknown. Researchers have suggested that saccadic suppression was probably achieved by contrast gain control, but this possibility has never been directly tested. In this study, we manipulated contrast gain control by contrast-adapting observers with sinusoidal gratings of different contrasts. Presaccadic and fixational contrast thresholds were measured and compared to give estimates of saccadic suppression at different adaptation states. Our results reconfirmed the selective saccadic suppression in achromatic condition, and further showed that, achromatic saccadic suppression diminished as contrast adaptation was accentuated, whereas no significant chromatic saccadic suppression was induced by greater contrast adaptation. Our data provided evidence for the involvement of contrast gain control in saccadic suppression in achromatic channel. We also discussed how the negative correlation between contrast adaptation and saccadic suppression could be interpreted with contrast gain control.

Our previous study reported that both glycoproteins gB and gH of the herpesvirus Marek's disease virus (MDV) contain eleven potential heptad repeat domains. These domains overlap with α-helix-enriched hydrophobic regions, including the gH-derived HR1 (gHH1) and HR3 (gHH3) and gB-derived HR1 (gBH1) regions, which demonstrate effective antiviral activity, with 50% inhibitory concentrations (IC(50)) of less than 12 µM. Plaque formation and chicken embryo infection assays confirmed these results. In this study, biochemical and biophysical analyses detected potential interactions between these peptides. gHH1, gHH3, and gBH1 were found to interact with each other in pairs. The complex formed by gHH3 and gBH1 showed the most stable interaction at a molar ratio of 1:3, the binding between gHH1 and gBH1 was relatively weak, and no interaction was observed between the three HR peptides. These results indicate that gHH3 and gBH1 are likely the key contributors to the interaction between gB and gH. Furthermore, each HR peptide from herpesvirus glycoproteins did not effectively inhibit virus infection compared with peptides from a class I enveloped virus. In this report, the HR mimic peptide modified with a double glutamic acid (EE) or a double lysine (KK) at the non-interactive sites (i.e., solvent-accessible sites) did not noticeably affect the antiviral activity compared with the wild-type HR peptide, whereas tandem peptides from gH-derived gHH1 and gB-derived gBH1 (i.e., gBH1-Linker-gHH1) produced efficient antiviral effects, unlike the individual peptides. The proposed interpretation of inhibition of entry has been addressed. Our results support the hypothesis that the interaction domain between glycoproteins gH and gB is a critical target in the design of inhibitors of herpesvirus infection.

Apurinic/apyrimidinic endonuclease 1 (APE1), which has the dual functions of both DNA repair and redox activity, has been reported to be highly expressed in non-small cell lung cancer (NSCLC), and this appears to be a characteristic related to chemotherapy resistance. In this study, we identified serum APE1 autoantibodies (APE1-AAbs) in NSCLC patients and healthy controls by immunoblotting and investigated the expression of APE1-AAbs by indirect ELISA from the serum of 292 NSCLC patients and 300 healthy controls. In addition, serum APE1-AAbs level alterations of 91 patients were monitored before and after chemotherapy. Our results showed that serum APE1-AAbs can be detected in both NSCLC patients and healthy controls. Serum APE1-AAbs were significantly higher than those of healthy controls and closely related to APE1 antigen levels both in tumor tissues and the peripheral blood. Moreover, the change in levels of serum APE1-AAbs in NSCLC is closely associated with the response to chemotherapy. These results suggest that APE1-AAbs is a potential tumor marker and predictor of therapeutic efficacy in NSCLC.

It has been reported that dense intratumoral infiltration of Foxp3 (+)Tregs (Tregs) was an independent factor for poor prognosis of breast cancer (BC) patients. However, the cytokines activating the Treg infiltration are not known. This study was undertaken to evaluate the role of CCL22 and TGF-β1 in this cascade and their prognostic significance for BC patients. 417 cases of invasive breast cancer were selected from the prior study cohort and the expressions of CCL22 and TGF-β1 were assessed by immunohistochemistry. It was identified that tumor secretion of CCL22 was positively correlated with the intratumoral Treg infiltration (P

It is thought that a Th1/Th17-weighted immune response plays a predominant role in the pathogenesis of psoriasis. Our findings now indicate a link between IL-9, a Th2 and Th9 cytokine, and Th17 pathway in psoriasis. In K5.hTGF-β1 transgenic mice, exhibiting a psoriasis-like phenotype, we found increased IL-9R and IL-9 expression in the skin and intradermal IL-9 injection induced Th17-related inflammation. IL-9 also promoted angiogenesis and VEGF and CD31 overexpression in mice in vivo and increased tube formation of human endothelial cells in vitro. Injecting anti-IL-9 antibody into K5.hTGF-β1 transgenic mice not only diminished inflammation (including skin infiltration by T cells, monocytes/macrophages, and mast cells) and angiogenesis but also delayed the psoriasis-like skin phenotype. Notably, injection of anti-psoriatic acting anti-IL-17 antibody reduced skin IL-9 mRNA and serum IL-9 protein levels in K5.hTGF-β1 transgenic mice and prevented IL-9-induced epidermal hyperplasia and inflammation of the skin of wild type mice. In addition, we observed that IL-9R expression in lesional skin from psoriasis patients was markedly higher than in healthy skin from control subjects. Moreover, IL-9 significantly enhanced IL-17A production by cultured human peripheral blood mononuclear cells or CD4+ T cells, especially in psoriasis patients. Thus, IL-9 may play a role in the development of psoriatic lesions through Th17-associated inflammation and angiogenesis.

BACKGROUND: The epidemiology of functional diarrhea and its impacts on Chinese remain unclear, and there are no data on the comparative epidemiology of functional diarrhea and diarrhea-predominant irritable bowel syndrome (IBS-D). This study was to explore the epidemiology of functional diarrhea and its impacts, and to identify its distinction from IBS-D. METHODS AND FINDINGS: A cross-sectional survey was conducted in 16078 respondents, who were interviewed under a randomized stratified multi-stage sampling design in five cities of China. All respondents completed the modified Rome II questionnaire, and the 36-item Short Form health survey (SF-36) was used for assessing health-related quality of life in 20% of the sample. Overall, 248 respondents (1.54%) had functional diarrhea and 277 (1.72%) had IBS-D. Functional diarrhea was positively associated with increasing age and body mass index (trend test P

BACKGROUND: The detection of signals of adverse drug events (ADEs) has increased because of the use of data mining algorithms in spontaneous reporting systems (SRSs). However, different data mining algorithms have different traits and conditions for application. The objective of our study was to explore the application of association rule (AR) mining in ADE signal detection and to compare its performance with that of other algorithms. METHODOLOGY/PRINCIPAL FINDINGS: Monte Carlo simulation was applied to generate drug-ADE reports randomly according to the characteristics of SRS datasets. Thousand simulated datasets were mined by AR and other algorithms. On average, 108,337 reports were generated by the Monte Carlo simulation. Based on the predefined criterion that 10% of the drug-ADE combinations were true signals, with RR equaling to 10, 4.9, 1.5, and 1.2, AR detected, on average, 284 suspected associations with a minimum support of 3 and a minimum lift of 1.2. The area under the receiver operating characteristic (ROC) curve of the AR was 0.788, which was equivalent to that shown for other algorithms. Additionally, AR was applied to reports submitted to the Shanghai SRS in 2009. Five hundred seventy combinations were detected using AR from 24,297 SRS reports, and they were compared with recognized ADEs identified by clinical experts and various other sources. CONCLUSIONS/SIGNIFICANCE: AR appears to be an effective method for ADE signal detection, both in simulated and real SRS datasets. The limitations of this method exposed in our study, i.e., a non-uniform thresholds setting and redundant rules, require further research.

Development of a suitable mouse model would facilitate the investigation of pathomechanisms underlying human psoriasis and would also assist in development of therapeutic treatments. However, while many psoriasis mouse models have been proposed, no single model recapitulates all features of the human disease, and standardized validation criteria for psoriasis mouse models have not been widely applied. In this study, whole-genome transcriptional profiling is used to compare gene expression patterns manifested by human psoriatic skin lesions with those that occur in five psoriasis mouse models (K5-Tie2, imiquimod, K14-AREG, K5-Stat3C and K5-TGFbeta1). While the cutaneous gene expression profiles associated with each mouse phenotype exhibited statistically significant similarity to the expression profile of psoriasis in humans, each model displayed distinctive sets of similarities and differences in comparison to human psoriasis. For all five models, correspondence to the human disease was strong with respect to genes involved in epidermal development and keratinization. Immune and inflammation-associated gene expression, in contrast, was more variable between models as compared to the human disease. These findings support the value of all five models as research tools, each with identifiable areas of convergence to and divergence from the human disease. Additionally, the approach used in this paper provides an objective and quantitative method for evaluation of proposed mouse models of psoriasis, which can be strategically applied in future studies to score strengths of mouse phenotypes relative to specific aspects of human psoriasis.

pMF1 is the only autonomously replicating plasmid that has been recently identified in myxobacteria. This study characterized the partitioning (par) system of this plasmid. The fragment that significantly increased the retaining stability of plasmids in Myxococcus cells in the absence of selective antibiotics contained three open reading frames (ORFs) pMF1.21-pMF1.23 (parCAB). The pMF1.22 ORF (parA) is homologous to members of the parA ATPase family, with the highest similarity (56%) to the Sphingobium japonicum ParA-like protein, while the other two ORFs had no homologs in GenBank. DNase I footprinting and electrophoretic mobility shift assays showed that the pMF1.23 (parB) product is a DNA-binding protein of iteron DNA sequences, while the product of pMF1.21 (parC) has no binding activity but is able to enhance the DNA-binding activity of ParB to iterons. The ParB protein autogenously repressed the expression of the par genes, consistent with the type Ib par pattern, while the ParC protein has less repressive activity. The ParB-binding iteron sequences are distributed not only near the partitioning gene loci but also along pMF1. These results indicate that the pMF1 par system has novel structural and functional characteristics.

DNA topoisomerase VI from Archaea, a heterotetrameric complex composed of two TopVIA and two TopVIB subunits, is involved in altering DNA topology during replication, transcription and chromosome segregation by catalyzing DNA strand transfer through transient double-strand breaks. The sequenced yeast and animal genomes encode only one homologue of the archaeal TopVIA subunit, namely Spo11, and no homologue of the archaeal TopVIB subunit. In yeast, Spo11 is essential for initiating meiotic recombination and this function appears conserved among other eukaryotes. In contrast to yeast and animals, studies in Arabidopsis and rice have identified three Spo11/TopVIA homologues and one TopVIB homologue in plants. Here, we further identified two novel Spo11/TopVIA homologues (named OsSpo11-4 and OsSpo11-5, respectively) that exist just in the monocot model plant Oryza sativa, indicating that at least five Spo11/TopVIA homologues are present in the rice genome. To reveal the biochemical function of the two novel Spo11/TopVIA homologues, we first examined the interactions among OsSpo11-1, OsSpo11-4, OsSpo11-5, and OsTopVIB by yeast two-hybrid assay. The results showed that OsSpo11-4 and OsTopVIB can self-interact strongly and among the 3 examined OsSpo11 proteins, only OsSpo11-4 interacted with OsTopVIB. Pull-down assay confirmed the interaction between OsSpo11-4 and OsTopVIB, which indicates that OsSpo11-4 may interact with OsTopVIB in vivo. Further in vitro enzymatic analysis revealed that among the above 4 proteins, only OsSpo11-4 exhibited double-strand DNA cleavage activity and its enzymatic activity appears dependent on Mg(2+) and independent of OsTopVIB, despite its interaction with OsTopVIB. We further analyzed the biological function of OsSpo11-4 by RNA interference and found that down-regulated expression of OsSpo11-4 led to defects in male meiosis, indicating OsSpo11-4 is required for meiosis.

Litchi has diverse fruit color phenotypes, yet no research reflects the biochemical background of this diversity. In this study, we evaluated 12 litchi cultivars for chromatic parameters and pigments, and investigated the effects of abscisic acid, forchlorofenron (CPPU), bagging and debagging treatments on fruit coloration in cv. Feizixiao, an unevenly red cultivar. Six genes encoding chalcone synthase (CHS), chalcone isomerase (CHI), flavanone 3-hydroxylase (F3H), dihydroflavonol 4-reductase (DFR), anthocyanidin synthase (ANS) and UDP-glucose: flavonoid 3-O-glucosyltransferase (UFGT) were isolated from the pericarp of the fully red litchi cv. Nuomici, and their expression was analyzed in different cultivars and under the above mentioned treatments. Pericarp anthocyanin concentration varied from none to 734 mg m(-2) among the 12 litchi cultivars, which were divided into three coloration types, i.e. non-red ('Kuixingqingpitian', 'Xingqiumili', 'Yamulong'and 'Yongxing No. 2'), unevenly red ('Feizixiao' and 'Sanyuehong') and fully red ('Meiguili', 'Baila', Baitangying' 'Guiwei', 'Nuomici' and 'Guinuo'). The fully red type cultivars had different levels of anthocyanin but with the same composition. The expression of the six genes, especially LcF3H, LcDFR, LcANS and LcUFGT, in the pericarp of non-red cultivars was much weaker as compared to those red cultivars. Their expression, LcDFR and LcUFGT in particular, was positively correlated with anthocyanin concentrations in the pericarp. These results suggest the late genes in the anthocyanin biosynthetic pathway were coordinately expressed during red coloration of litchi fruits. Low expression of these genes resulted in absence or extremely low anthocyanin accumulation in non-red cultivars. Zero-red pericarp from either immature or CPPU treated fruits appeared to be lacking in anthocyanins due to the absence of UFGT expression. Among these six genes, only the expression of UFGT was found significantly correlated with the pericarp anthocyanin concentration (r = 0.84). These results suggest that UFGT played a predominant role in the anthocyanin accumulation in litchi as well as pericarp coloration of a given cultivar.

Biogenesis of membrane proteins is controlled by the protein homeostasis (proteostasis) network. We have been focusing on protein quality control of γ-aminobutyric acid type A (GABAA) receptors, the major inhibitory neurotransmitter-gated ion channels in mammalian central nervous system. Proteostasis deficiency in GABAA receptors causes loss of their surface expression and thus function on the plasma membrane, leading to epilepsy and other neurological diseases. One well-characterized example is the A322D mutation in the α1 subunit that causes its extensive misfolding and expedited degradation in the endoplasmic reticulum (ER), resulting in autosomal dominant juvenile myoclonic epilepsy. We aimed to correct misfolding of the α1(A322D) subunits in the ER as an approach to restore their functional surface expression. Here, we showed that application of BIX, a specific, potent ER resident HSP70 family protein BiP activator, significantly increases the surface expression of the mutant receptors in human HEK293T cells and neuronal SH-SY5Y cells. BIX attenuates the degradation of α1(A322D) and enhances their forward trafficking and function. Furthermore, because BiP is one major target of the two unfolded protein response (UPR) pathways: ATF6 and IRE1, we continued to demonstrate that modest activations of the ATF6 pathway and IRE1 pathway genetically enhance the plasma membrane trafficking of the α1(A322D) protein in HEK293T cells. Our results underlie the potential of regulating the ER proteostasis network to correct loss-of-function protein conformational diseases. [ABSTRACT FROM AUTHOR]