Yellow-Green Leaf 19 Encoding a Specific and Conservative Protein for Photosynthetic Organisms Affects Tetrapyrrole Biosynthesis, Photosynthesis, and Reactive Oxygen Species Metabolism in Rice.

Chlorophyll is the main photosynthetic pigment and is crucial for plant photosynthesis. Leaf color mutants are widely used to identify genes involved in the synthesis or metabolism of chlorophyll. In this study, a spontaneous mutant, yellow-green leaf 19 (ygl19), was isolated from rice (Oryza sativa). This ygl19 mutant showed yellow-green leaves and decreased chlorophyll level and net photosynthetic rate. Brown necrotic spots appeared on the surface of ygl19 leaves at the tillering stage. And the agronomic traits of the ygl19 mutant, including the plant height, tiller number per plant, and total number of grains per plant, were significantly reduced. Map-based cloning revealed that the candidate YGL19 gene was LOC_Os03g21370. Complementation of the ygl19 mutant with the wild-type CDS of LOC_Os03g21370 led to the restoration of the mutant to the normal phenotype. Evolutionary analysis revealed that YGL19 protein and its homologues were unique for photoautotrophs, containing a conserved Ycf54 functional domain. A conserved amino acid substitution from proline to serine on the Ycf54 domain led to the ygl19 mutation. Sequence analysis of the YGL19 gene in 4726 rice accessions found that the YGL19 gene was conserved in natural rice variants with no resulting amino acid variation. The YGL19 gene was mainly expressed in green tissues, especially in leaf organs. And the YGL19 protein was localized in the chloroplast for function. Gene expression analysis via qRT-PCR showed that the expression levels of tetrapyrrole synthesis-related genes and photosynthesis-related genes were regulated in the ygl19 mutant. Reactive oxygen species (ROS) such as superoxide anions and hydrogen peroxide accumulated in spotted leaves of the ygl19 mutant at the tillering stage, accompanied by the regulation of ROS scavenging enzyme-encoding genes and ROS-responsive defense signaling genes. This study demonstrates that a novel yellow-green leaf gene YGL19 affects tetrapyrrole biosynthesis, photosynthesis, and ROS metabolism in rice.

The characteristics of multi-substrates (low and high C/N) anaerobic digestion: focus on energy recovery and the succession of methanogenic pathway.

Anaerobic digestion of common rural wastes (human feces (HF), food waste (FW) and lawn grass (LG)) were studied considering the specific methane yield, process parameters and microbial characteristics (mainly microbial community and pathogenic bacteria). The results showed that co-digestion of multiple substrates obtained high digestion performance when the total solid (TS) was 4%. The optimal co-digestion ratio of HF, FW, and LG was 33-56%, 21-38% and 20-40%, respectively. The digestion system containing HF underwent ammonia inhibition, which leads to the succession of the methanogenesis pathway from the acetoclastic pathway to the hydrogenotrophic pathway. Simultaneously, the dominant methanogenic archaea changed from Methanosaeta to Methanobacterium and Methanosarcina. Co-digestion reduced Salmonella's absolute concentration. The recovered energy and nitrogen could meet 52-109 % energy demand of rural community and all nitrogen demand in lawn fertilization, respectively. The main rural organic wastes could be recycled by anaerobic digestion, considering the flexibility of substrate ratio.

[Effects of BiejiaYugan Granule on TGF-ß1/Smads pathway in rats with hepatic fibrosis caused by compound factors].

Objective: To investigate the therapeutic effects of Biejia Yugan Granule on hepatic fibrosis caused by compound factors in rats and its effect on TGF-ß1/Smads signaling pathway. Methods: SD rats were randomly divided into blank control group, model control group, colchicine group, Biejia Yugan Granule low, medium and high dose (1.85, 3.70, 7.40 g/kg) groups (n= 8 in each group). The rat model of hepatic fibrosis was established by treating with 5% alcohol 15 ml/kg (ig) everyday and injecting with 40% carbon tetrachloride (sc) twice a week for 42 days. The effects of Biejia Yugan Granule on liver function, liver index and water content, serum hepatic fibrosis related indicators, key proteins and gene expression of TGF-ß1/Smads signaling pathway in rats were observed. Results: Biejia Yugan Granule at the doses of 1.85, 3.70 and 7.40 g/kg could decrease the serum levels of ALT, AST, ALP and HA, PCⅢ, C-Ⅳ, LN significantly, reduce the water content of liver tissue leads to the decrease of liver index, regulate the liver tissue TGF-ß1, Smad3 mRNA and Smad7 mRNA expressions. Conclusion: Biejia Yugan Granule has obvious effects of reducing enzyme and protecting liver and inhibiting hepatic fibrosis, and inhibiting TGF-ß1/Smads signaling pathway is one of its mechanisms of anti-hepatic fibrosis.

[Effects of Butylphthalide on airway mucus hypersecretion, IL-13 and TNF-α in asthmatic mice].

Objective: To investigate the effects of Butylphthalide (NBP) on airway mucus hypersecretion, interleukin-13 (IL-13) and tumor necrosis factor-α (TNF-α) in asthmatic mice. Methods: The mice were randomly divided into control group, asthma group, DEX group and high, medium and low doses of NBP (100, 50, 25 mg/kg) groups (n=12). Ovalbumin (OVA) injection was sensitized on the 1st, 8th, and 15th day of the experiment, and OVA was inhaled on the 22nd day to stimulate for 5 weeks to replicate the asthma model, and 20 mg/kg of NBP was given for intervention before the challenge. Finally, the asthma behavior, the secretion of goblet cells and Mucin 5ac (Muc5ac)were observed, and meanwhile the viscosity of bronchoalveolar lavage fluid (BALF) and the levels of Muc5ac, IL-13 and TNF-α in BALF were measured by ELISA. Results: Compared with the control group, the degree of sneezing, nose scratching and asthma, the proliferation of airway epithelial goblet cells and secretion of Muc5ac in the asthma group were increased significantly (P＜0.01), meanwhile, the viscosity of BALF and the contents of Muc5ac, IL-13 and TNF-α were also increased significantly (P＜0.01). Compared with the asthma group, the above behavioral scores of asthma were decreased significantly (P＜0.01) after the intervention of 25, 50 and 100 mg/kg NBP, as well as the proliferation of airway epithelial goblet cells, secretion of Muc5ac, the viscosity of BALF and the contents of Muc5ac, IL-13 and TNF-α were significantly lower than those of the asthma group (P＜0.05, 0.01). Conclusion: NBP has the effect of anti-asthma by inhibiting mucus hypersecretion, and one of its mechanisms is to alleviate the abnormal expressions of IL-13 and TNF-α.

UDP-N-Acetylglucosamine Pyrophosphorylase 2 (UAP2) and 1 (UAP1) Perform Synergetic Functions for Leaf Survival in Rice.

Functional inactivation of UDP-N-acetylglucosamine pyrophosphorylase 1 (UAP1) induces defense response-related lesion-mimic spots and subsequent early senescence in every newly grown leaf of the rice mutant uap1 after a short period's normal growth. However, the molecular mechanism of these leaves sustaining the short period's survival is still unknown. Phenotypic and molecular studies show that defense response-related lesion-mimic spots and early leaf senescence appear on the normally grown uap1 leaf and aggravate with the growth time. Bioinformatic analysis reveals that UAP proteins are evolutionarily conserved among eukaryotes, and there exists UAP2 protein except UAP1 protein in many higher organisms, including rice. Rice UAP2 and UAP1 proteins present high sequence identities and very similar predicted 3D structures. Transcriptional expression profile of the UAP2 gene decreases with the appearance and aggravating of leaf spots and early senescence of uap1, implying the role of the UAP2 gene in maintaining the initial normal growth of uap1 leaves. Enzymatic experiments verified that the UAP2 protein performs highly similar UAP enzymatic activity with the UAP1 protein, catalyzing the biosynthesis of UDP-GlcNAc. And these two UAP proteins are found to have the same subcellular localization in the cytoplasm, where they most presumably perform their functions. Overexpression of the UAP2 gene in uap1 plants succeeds to rescue their leaf mutant phenotype to normal, providing direct evidence for the similar function of the UAP2 gene as the UAP1 gene. The UAP2 gene is mainly expressed in the young leaf stage for functions, while the UAP1 gene is highly expressed during the whole leaf developmental stages. Based on these findings, it is suggested that UAP2 and UAP1 play key roles in rice leaf survival during its development in a synergetic manner, protecting the leaf from early senescence.

Genome-wide identification and characterization of long non-coding RNAs involved in flag leaf senescence of rice.

KEY MESSAGE: This study showed the systematic identification of long non-coding RNAs (lncRNAs) involving in flag leaf senescence of rice, providing the possible lncRNA-mRNA regulatory relationships and lncRNA-miRNA-mRNA ceRNA networks during leaf senescence. LncRNAs have been reported to play crucial roles in diverse biological processes. However, no systematic identification of lncRNAs associated with leaf senescence in plants has been studied. In this study, a genome-wide high throughput sequencing analysis was performed using rice flag leaves developing from normal to senescence. A total of 3953 lncRNAs and 38757 mRNAs were identified, of which 343 lncRNAs and 9412 mRNAs were differentially expressed. Through weighted gene co-expression network analysis (WGCNA), 22 continuously down-expressed lncRNAs targeting 812 co-expressed mRNAs and 48 continuously up-expressed lncRNAs targeting 1209 co-expressed mRNAs were considered to be significantly associated with flag leaf senescence. Gene Ontology results suggested that the senescence-associated lncRNAs targeted mRNAs involving in many biological processes, including transcription, hormone response, oxidation-reduction process and substance metabolism. Additionally, 43 senescence-associated lncRNAs were predicted to target 111 co-expressed transcription factors. Interestingly, 8 down-expressed lncRNAs and 29 up-expressed lncRNAs were found to separately target 12 and 20 well-studied senescence-associated genes (SAGs). Furthermore, analysis on the competing endogenous RNA (CeRNA) network revealed that 6 down-expressed lncRNAs possibly regulated 51 co-expressed mRNAs through 15 miRNAs, and 14 up-expressed lncRNAs possibly regulated 117 co-expressed mRNAs through 21 miRNAs. Importantly, by expression validation, a conserved miR164-NAC regulatory pathway was found to be possibly involved in leaf senescence, where lncRNA MSTRG.62092.1 may serve as a ceRNA binding with miR164a and miR164e to regulate three transcription factors. And two key lncRNAs MSTRG.31014.21 and MSTRG.31014.36 also could regulate the abscisic-acid biosynthetic gene BGIOSGA025169 (OsNCED4) and BGIOSGA016313 (NAC family) through osa-miR5809. The possible regulation networks of lncRNAs involving in leaf senescence were discussed, and several candidate lncRNAs were recommended for prior transgenic analysis. These findings will extend the understanding on the regulatory roles of lncRNAs in leaf senescence, and lay a foundation for functional research on candidate lncRNAs.

[Effects of Radix Angelicae Sinensis on airway mucus hypersecretion and the TNF-α/NF-κB signaling pathway in Yin-deficiency asthmatic mice].

Objective: To investigate the therapeutic effects of Radix Angelicae Sinensis (RADA) on airway mucus hypersecretion and the tumor necrosis factor-α/ nuclear factor- κB (TNF-α/NF-κB) signaling pathway in Yin-deficiency asthma mice. Methods: KM mice were randomly divided into control group, model group, ambroxol group and RADA low, medium and high dose (2, 4 and 8 g/kg) group(n=12). Ovalbumin and the thyroid gland were used to replicate the model of Yin-deficiency asthma. Asthma symptoms in mice , immune globulin E (IgE) , TNF-α , and the expressions of Mucin 5ac (Muc5ac) and NF- κB in lung tissue were observed under the intervention of RADA. Results: RADA at the doses of 2,4 and 8 g/kg could alleviate the asthma symptoms of Yin-deficiency asthma mice significantly, reduce the levels of IgE in serum and TNF-α in bronchoalveolar lavage fluid (BALF), and inhibite the overexpressions of Muc5ac and NF- κB in lung tissue. Conclusion: RADA has significant anti-asthmatic effect. One of its mechanisms is to inhibit TNF-α/NF- κB signaling pathway and to alleviate airway mucus hypersecretion.

[Effects of Biejia Yugan Granule on rat with ethanol-induced hepatic fibrosis].

Objective: To investigate the prevention and treatment effect of Biejia Yugan Granule (BYG) on ethanol-induced hepatic fibrosis (EHF) rats. Methods: SD rats were randomly divided into blank control group, model group, BYG group, colchicine group and BYG low and BYG high dose groups (n=8). The EHF rat model was established by intragastric edible ethanol with a gradually increased dose. Briefly, the rats of model group, colchicine group and BYG low and high dose groups were given gavage of 5 g/(kg·d) ethanol at week 1～4, 7 g/(kg·d) ethanol at week 5～8, 9 g/(kg·d) ethanol at week 9～12 and 9.5 g/(kg·d) ethanol at week 13～24. And the other two groups were treated with equal volume water. At the same time, the corresponding drugs were administrated daily: BYG group was treated with Biejia Yugan Granules 5.55 g/kg, colchicine group was treated with colchicine 0.1 mg/kg, BYG low-dose and high-group were treated with Biejia Yugan Granules 1.85 and 5.55 g/kg respectively. The blank control group and model control group were given the same amount of purified water. On the 169th day of the experiment, the effects of BYG on the macroscopic changes of rat liver organs, the water content of liver tissue and the pathological changes of fibrosis, the content of hydroxy proline (Hyp) in liver tissue and the expression levels of α-SMA and CREB were observed. Results: BYG at the doses of 1.85 and 5.55 g/kg could significantly improve the macroscopic changes of liver and pathological changes of liver tissue fibrosis in rats with EHF, reduce the contents of water and Hyp in liver tissue, and down-regulate the expressions of α-SMA and CREB. Conclusion: BYG has obvious effect on inhibiting EHF and one of its mechanisms is down-regulate the content of CREB.

[Preventive and therapeutic effects of Qiwei Yugan Granule on hepatic fibrosis in rats].

Objective: To investigate the preventive and therapeutic effects of Qiwei Yugan Granule (QYG) on hepatic fibrosis in rats based on MMP-13/TIMP-1 imbalance. Methods: The rats were randomly divided into control group, model group, colchicine group (1.0×10-4 g/kg) and QYG treated groups (3.7, 7.4, 14.8 g/kg) (n=8). The rat model of hepatic fibrosis was established by injected with carbon tetrachloride subcutaneously for 4 weeks and treated with ethanol by gavage for 6 weeks. The effects of QYG on liver function, histopathology of liver, related indexes of serum liver fibrosis, and MMP-13, TIMP-1 in hepatic tissue were observed. Results: QYG at the doses of 14.8、7.4、3.7 g/kg could significantly decrease the serum levels of ALT, AST, HA, PCⅢ and C-Ⅳ, relieve the pathological changes of hepatic fibrosis, increase the activity of MMP-13, decrease the activity of TIMP-1 and alleviate the imbalance of MMP-13/TIMP-1. Among them, QYG had a certain trend of dose-effect relationship with TIMP-1 and MMP-13/TIMP-1 (P＜0.05, 0.01). Conclusion: QYG has the effect of preventing and treating liver fibrosis and one of mechanisms is to promote MMP-13/TIMP-1 to restore balance.

Butylphthalide ameliorates airway inflammation and mucus hypersecretion via NF-κB in a murine asthma model.

Butylphthalide (NBP) is a phthalide compound contained in Angelicae Sinensis Radix which is one of the most widely used traditional Chinese medicines. This study aims to explore the therapeutic effect of NBP on airway inflammation, mucus hypersecretion and their possible mechanism in asthma mice. BALB/c mice were sensitized and challenged with ovalbumin (OVA) for establishment of asthma model and then treated with NBP during day 22-77. The pulmonary function of the mice was determined, and the pathology of lung tissue and goblet cell hyperplasia were observed through analyzing inflammation scores and goblet cell percentage, respectively. Cytokine IL-4, IL-8, IL-13 and tumor necrosis factor-alpha (TNF-α) in bronchoalveolar lavage fluid (BALF) and total immunogloblin E (T-IgE) and OVA-specific IgE in serum were examined by enzyme-linked immunosorbent assay (ELISA). The expressions of Mucin 5AC (Muc5ac) and nuclear transcription factor-kappa B (NF-κB) in lung tissues were evaluated by immunohistochemistry, western blot and real-time polymerase chain reaction (RT-PCR). The results show that 50 mg/kg NBP significantly reduced OVA-induced increase in inflammation scoring, goblet cell percentage and mucus secretion of airway tissue, and improved the pulmonary function. NBP could also decrease IL-4, IL-8 IL-13, and TNF-α in BALF and T-IgE and OVA-specific IgE in serum. The expression of Muc5ac and NF-κB in lung tissue was significantly down-regulated after NBP treatment. This study suggested that NBP may effectively inhibit airway inflammation and mucus hypersecretion in asthma by modulating NF-κB activation.

High Nighttime Temperature Induces Antioxidant Molecule Perturbations in Heat-Sensitive and Heat-Tolerant Coisogenic Rice ( Oryza sativa) Strains.

Global warming-associated increases in temperature, particularly at nighttime, are detrimental to rice yield and quality. Metabolomic profiling was used to examine and compare the short-term extreme high nighttime temperature-induced molecular perturbations in rice ( Oryza sativa) coisogenic strains with contrasting heat-tolerances at the first stage of seed ripening. Compared to the heat-sensitive strain, antioxidant molecules were higher in abundance in the heat-tolerant strain, whereas the abundances of molecules involved in photosynthesis, nucleotide catabolism, and the S-adenosylmethionine (SAM) cycle varied only slightly. Thus, we proposed that the high abundance of antioxidant molecules in the heat-tolerant strain alleviated cellular oxidative stress, which protected photosynthesis, nucleotide catabolism, and the SAM cycle, leading to good grain filling.

microRNA-494 is a potential prognostic marker and inhibits cellular proliferation, migration and invasion by targeting SIRT1 in epithelial ovarian cancer.

Ovarian cancer is one of the most common types of gynecological malignancy worldwide, and is the fourth leading cause of cancer-associated mortality among women. Despite improvements in therapeutic treatments, the prognosis for epithelial ovarian cancer (EOC) remains poor, mainly due to the rapid growth and metastasis of ovarian cancer tumors. An increasing number of studies have indicated that microRNAs (miRNAs) are involved in the carcinogenesis and progression of human cancer, suggesting that miRNAs may be used in clinical prognosis and as a therapeutic target in EOC. The aim of the present study was to investigate the expression levels of miRNA-494 in EOC tissues and cell lines. The clinical significance of miRNA-494 in patients with EOC was also evaluated. The results demonstrated that miRNA-494 was significantly downregulated in EOC tissues and cell lines. Low expression levels of miRNA-494 were associated with poor prognostic features, including International Federation of Gynecology and Obstetrics stage, tumor size and lymph node metastasis. In vitro functional studies demonstrated that overexpression of miRNA-494 inhibited proliferation, migration and invasion in EOC cells. By contrast, knockdown of miRNA-494 enhanced cell growth, migration and invasion in EOC cells. Notably, sirtuin 1 (SIRT1) was identified as a direct target of miRNA-494 in EOC. Furthermore, MTT, cell migration and invasion assays verified that EOC cell proliferation, migration and invasion were completely restored with forced miRNA-494 expression and SIRT1 restoration. Together, these findings suggest that miRNA-494 is a potential prognostic marker, and may provide novel therapeutic regimens of targeted therapy for EOC.

RUNX3 gene methylation in epithelial ovarian cancer tissues and ovarian cancer cell lines.

Methylation plays an important role in the regulation of gene expression in many cancer tissues. RUNX3 is an important tumor suppressor gene located on human chromosome 1p36.1, and many tumors do not express it due to methylation of the promoter region of the CpG island. The molecular mechanisms involved in RUNX3 gene expression and epithelial ovarian cancer are not fully understood. This study investigates the relationship between RUNX3 methylation and expression in ovarian cancer. The methylation of the RUNX3 gene promoter region was measured in 32 primary epithelial ovarian cancer samples and corresponding nonmalignant ovarian tissues, 36 benign epithelial ovarian tumor tissues, and 10 normal ovarian tissues by methylation-specific PCR (MSP) and RT-PCR. The relationships between RUNX3 methylation status, expression, and clinicopathologic characteristics were analyzed. RUNX3 methylation was further assessed by MSP and RT-PCR before and after 5-aza-2'-deoxycytidine (5-aza-dc) treatment in normal and cancer cell lines. We detected RUNX3 methylation in 53.1% of primary ovarian cancer tumors, 16.7% of benign ovarian tumors, and 28% of nonmalignant tissues surrounding ovarian cancers. No methylation was detected in normal ovarian tissues. No significant correlation between RUNX3 methylation and clinicopathological characteristics was observed. The RT-PCR results found RUNX3 expression in all normal ovarian tissues (10/10) and in most of the unmethylated ovarian cancer tissues (12/15); in contrast, it was not detected in most of the RUNX3-methylated ovarian cancer tissues (16/17). Our data suggest that methylation plays a critical role in the regulation of RUNX3 repression, and that it is significantly correlated with RUNX3 mRNA expression in ovarian cancer tissues (p = 0.006).