Cell-Permeable Ubiquitin and Histone Tools for Studying Post-translational Modifications.

Protein post-translational modifications (PTMs) regulate nearly all biological processes in eukaryotic cells, and synthetic PTM protein tools are widely used to detect the activity of the related enzymes and identify the interacting proteins in cell lysates. Recently, the study of these enzymes and the interacting proteome has been accomplished in live cells using cell-permeable PTM protein tools. In this concept, we will introduce cell penetrating techniques, the syntheses of cell-permeable PTM protein tools, and offer some future perspective.

Application and prospect of gene chip in genetic breeding of livestock and poultry.

Gene chip is a high-throughput technique for detecting specific DNA sequences by DNA or DNA-RNA complementary hybridization, among which SNP genotyping chips have been widely employed in the animal genetics and breeding, and have made great achievements in cattle (Bos taurus), pigs (Sus scrofa), sheep (Caprinae), chickens (Gallus gallus) and other livestock. However, genomic selection applied in production merely uses genomic information and cannot fully explain the molecular mechanism of complex traits genetics, which limits the accuracy of genomic selection. With the continuous progresses in epigenetic research, the development of commercial methylation chips and the application of the epigenome-wide association study (EWAS), DNA methylation has been extensively used to draw the causal connections between genetics and phenotypes. In the future, it is hopefully expected to develop methylation chips customized for livestock and poultry and explore methylation sites significantly related to economic traits of livestock and poultry through EWAS thereby extending the understanding of causal variation of complex traits. Combining methylation chips and SNP chips, we can capture the epigenomic and genomic information of livestock and poultry, interpret genetic variation more precisely, improve the accuracy of genome selection, and promote the fine evolution of molecular genetic breeding of livestock and poultry. In this review, we summarize the application of SNP chips and depict the prospects of the application of methylation chips in livestock and poultry. This review will provide valuable insights for further application of gene chips in farm animal breeding.

An ABA-serotonin module regulates root suberization and salinity tolerance.

Suberin in roots acts as a physical barrier preventing water/mineral losses. In Arabidopsis, root suberization is regulated by abscisic acid (ABA) and ethylene in response to nutrient stresses. ABA also mediates coordination between microbiota and root endodermis in mineral nutrient homeostasis. However, it is not known whether this regulatory system is common to plants in general, and whether there are other key molecule(s) involved. We show that serotonin acts downstream of ABA in regulating suberization in rice and Arabidopsis and negatively regulates suberization in rice roots in response to salinity. We show that ABA represses transcription of the key gene (OsT5H) in serotonin biosynthesis, thus promoting root suberization in rice. Conversely, overexpression of OsT5H or supplementation with exogenous serotonin represses suberization and reduces tolerance to salt stress. These results identify an ABA-serotonin regulatory module controlling root suberization in rice and Arabidopsis, which is likely to represent a general mechanism as ABA and serotonin are ubiquitous in plants. These findings are of significant importance to breeding novel crop varieties that are resilient to abiotic stresses and developing strategies for production of suberin-rich roots to sequestrate more CO2 , helping to mitigate the effects of climate change.

An alanine to valine mutation of glutamyl-tRNA reductase enhances 5-aminolevulinic acid synthesis in rice.

KEY MESSAGE: An alanine to valine mutation of glutamyl-tRNA reductase's 510th amino acid improves 5-aminolevulinic acid synthesis in rice. 5-aminolevulinic acid (ALA) is the common precursor of all tetrapyrroles and plays an important role in plant growth regulation. ALA is synthesized from glutamate, catalyzed by glutamyl-tRNA synthetase (GluRS), glutamyl-tRNA reductase (GluTR), and glutamate-1-semialdehyde aminotransferase (GSAT). In Arabidopsis, ALA synthesis is the rate-limiting step in tetrapyrrole production via GluTR post-translational regulations. In rice, mutations of GluTR and GSAT homologs are known to confer chlorophyll deficiency phenotypes; however, the enzymatic activity of rice GluRS, GluTR, and GSAT and the post-translational regulation of rice GluTR have not been investigated experimentally. We have demonstrated that a suppressor mutation in rice partially reverts the xantha trait. In the present study, we first determine that the suppressor mutation results from a G → A nucleotide substitution of OsGluTR (and an A → V change of its 510th amino acid). Protein homology modeling and molecular docking show that the OsGluTRA510V mutation increases its substrate binding. We then demonstrate that the OsGluTRA510V mutation increases ALA synthesis in Escherichia coli without affecting its interaction with OsFLU. We further explore homologous genes encoding GluTR across 193 plant species and find that the amino acid (A) is 100% conserved at the position, suggesting its critical role in GluTR. Thus, we demonstrate that the gain-of-function OsGluTRA510V mutation underlies suppression of the xantha trait, experimentally proves the enzymatic activity of rice GluRS, GluTR, and GSAT in ALA synthesis, and uncovers conservation of the alanine corresponding to the 510th amino acid of OsGluTR across plant species.

An edible molecularly imprinted material prepared by a new environmentally friendly deep eutectic solvent for removing oxalic acid from vegetables and human blood.

A novel deep eutectic solvent-magnetic molecularly imprinted polymer (DES-MMIP) for the specific removal of oxalic acid (OA) was prepared by an environmentally friendly deep eutectic solvent, consisting of betaine, citric acid, and glycerol, which acted as the functional monomer for polymerization. The structure and morphology of DES-MMIPs were studied by X-ray diffraction, scanning and transmission electron microscopy, thermal gravimetric analysis, Fourier transform infrared spectroscopy, and vibrating sample magnetometer. DES-MMIPs had a core-shell structure, with magnetic iron oxide as the core, and showed good thermal stability and high adsorption capacity (18.73 mg/g) for OA. The adsorption process of OA by DES-MMIPs followed the pseudo-second-order kinetic model and Langmuir isotherm model. DES-MMIPs had significant selectivity for OA and their imprinting factor was 3.26. When applied to real samples, high performance liquid chromatography analysis showed that DES-MMIPs could remove OA from both spinach and blood serum. These findings provide potential methods for removal of OA from vegetables and for specific removal of OA in renal dialysis.

[Exploration of emulsifying material basis of Angelicae Sinensis Radix volatile oil based on partial least squares and hydrophile-lipophile balance value].

This study explores the emulsifying material basis of Angelicae Sinensis Radix volatile oil (ASRVO) based on partial least squares (PLS) method and hydrophile-lipophile balance (HLB) value.The turbidity of ASRVO emulsion samples from Gansu,Yunnan,and Qinghai was determined and the chemical components in the emulsion were analyzed by GC-MS.The PLS model was established with the chemical components as the independent variable and the turbidity as the dependent variable and evaluated with indexes R~2X and R~2Y.The chemical components which were in positive correlation with the turbidity were selected and the HLB values were calculated to determine the emulsification material basis of ASRVO.The PLS models for the 81 emulsion samples had high R~2X and R~2Y values,which showed good fitting ability.Seven chemical components,2-methoxy-4-vinylphenol,trans-ligustilide,3-butylidene-1(3H)-isobenzofuranone,dodecane,1-methyl-4-(1-methylethylidene)-cyclohexene,trans-beta-ocimene,and decane,had positive correlation with turbidity.Particularly,the HLB value of 2-methoxy-4-vinylphenol was 4.4,which was the HLB range of surfactants to be emulsifiers and 2-methoxy-4-vinylphenol was positively correlated with turbidity of the ASRVO emulsion samples from the main producing area.Therefore,2-methoxy-4-vinylphenol was the emulsifying material basis of ASRVO.The selected emulsifying substances can lay a foundation for exploring the emulsification mechanism and demulsification solution of ASRVO.

[Research progress on antibacterial activity of herbal volatile oil].

Due to worldwide abuse of chemical antibiotics and continuous emergence of "superbugs", the harm of bacterial drug resistance to human beings has become more and more serious. Therefore, it is of great significance to look for green antibiotics with a wide range of sources, broad antibacterial spectrum, non-toxicity or low toxicity, environmentally friendliness, diverse active components and low drug resistance. The volatile oil of traditional Chinese medicine is a kind of volatile oily liquid that exists in plants and can be distilled with steam and immiscible with water. Because of its good potential to resist drug-resistant pathogens, it is widely used in food, medicine and other fields. This paper summarized the antibacterial advantages and characteristics of volatile oil of traditional Chinese medicine, and the antibacterial effect and antibacterial mechanism of combined application of volatile oil of traditional Chinese medicine, in order to provide some theoretical basis and study ideas for solving the problem of bacterial drug resistance and developing natural and green antibiotics.

Genome-wide identification, evolution and expression analysis of cyclic nucleotide-gated channels in tobacco (Nicotiana tabacum L.).

Tobacco (Nicotiana tabacum) serve as the top leading commercial, non-food, and model crop worldwide. Cyclic nucleotide-gated channels (CNGCs) are ligand-gated, calcium-permeable, divalent, cation-selective channels, involved in important biological functions. Here, we systematically characterized thirty-five CNGC genes in the genome of Nicotiana tabacum, and classified into four phylogenetic groups. Evolutionary analysis showed that NtabCNGC family of N. tabacum originated from the parental genome of N. sylvestris and N. tomentosiformis, and further expanded via tandem and segmental duplication events. Tissue-specific expression analysis showed that twenty-three NtabCNGC genes are involved in the development of various tobacco tissues. Subsequent RT-qPCR analyses indicated that these genes are sensitive towards external abiotic and biotic stresses. Notable performances were exhibited by group-I and IV CNGC genes against black shank, Cucumber mosaic virus, Potato virus Y, cold, drought, and cadmium stresses. Our analyses also suggested that NtabCNGCs can be regulated by phosphorylation and miRNAs, and multiple light, temperature, and pathogen-responsive cis-acting regulatory elements present in promotors. These results will be useful for elaborating the biological roles of NtabCNGCs in tobacco growth and development.

[Mechanism of Aurantii Fructus Immaturus volatile oil in treatment of slow transit constipation based on network pharmacology].

To construct the active component-action target network diagram and protein-protein interaction(PPI) network diagram of Aurantii Fructus Immaturus volatile oil, so as to explore the mechanism of Aurantii Fructus Immaturus volatile oil in the treatment of slow transit constipation(STC) by analyzing the functions and pathways involved in the target. The chemical constituents of Aurantii Fructus Immaturus volatile oil were determined by gas chromatography-mass spectrometry(GC-MS). The targets of Aurantii Fructus Immaturus volatile oil were studied by PubChem, TCMSP, STITCH and Swiss Target Prediction. OMIM, Genecards-Search Resuits and TTD were used to screen out the targets of Slow Transit Constipation. The active component-action targets and PPI network diagram were constructed by Cytoscape 3.7.1. The target organ distribution was analyzed by BioGPS database. GO and KEGG pathways involved in the targets were analyzed by R language. The molecular docking between the components and the targets was verified by Discovery Studio 2.5 software. Finally, 15 volatile oil compounds from Aurantii Fructus Immaturus were detected, and 115 targets of volatile oil in the treatment of STC were predicted. GO enrichment analysis showed that the activity of Aurantii Fructus Immaturus volatile oil mainly involved blood circulation, circulation system process, response to steroid hormone, signal release and other biological processes. There were 23 KEGG enrichment pathways, among which Neuroactive ligand-receptor interaction, cAMP signaling pathway, Endocrine resistance, Calcium signaling pathway and Serotonergic synapse pathways played a significant role in STC. The results of molecular docking showed that relevant target proteins for the treatment of STC were ACHE, PTGS2, SLC6 A2 and CNR2.The multi-component, multi-target and multi-pathwaycharacteristics of Aurantii Fructus Immaturus volatile oil were revealed by network pharmacology, which provided a new therapeutic idea and method for the further study of the mechanism of Aurantii Fructus Immaturus volatile oil in the treatment of STC.

The mortality risk factor of community acquired pneumonia patients with chronic obstructive pulmonary disease: a retrospective cohort study.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is one of the most common comorbidities in community acquired pneumonia (CAP) patients. We aimed to investigate the characteristics and mortality risk factors of COPD patients hospitalized with CAP. METHODS: A retrospective cohort study was conducted at Shanghai Pulmonary Hospital and Shanghai Dahua Hospital. Clinical and demographic data in patients diagnosed with CAP were collected between January 2015 and June 2016. Logistic regression analysis was performed to screen mortality risk factors of COPD patients hospitalized with CAP. RESULTS: Of the total 520 CAP patients, 230 (44.2%) patients had been diagnosed comorbid with COPD (COPD-CAP). CAP patients comorbid with COPD patients had higher rate of need for ICU admission (18.3% vs 13.1%) and need for NIMV (26.1% vs 1.4%) than without COPD (nCOPD-CAP). The PSI, CURB-65 and APACHE-II scores in COPD-CAP patients were higher than that in nCOPD-CAP patients (95 vs 79, P < 0.001; 1 vs 1, P < 0.001; 13 vs 8, P < 0.001, respectively). Logistic regression analysis indicated that aspiration, D-dimer > 2.0 µg/mL and CURB-65 ≥ 3 were risk factors associated with in-hospital mortality ((odd ratio) OR = 5.678, OR = 4.268, OR = 20.764, respectively) in COPD-CAP patients. The risk factors associated with 60-day mortality in COPD-CAP patients were comorbid with coronary heart disease, aspiration, need for NIMV (non-invasive mechanical ventilation) and CURB-65 ≥ 3 (OR = 5.206, OR = 7.921, OR = 3.974, OR = 18.002, respectively). CONCLUSIONS: COPD patients hospitalized with CAP had higher rate of need for NIMV, need for ICU admission and severity scores than those without COPD. Aspiration, D-dimer > 2.0 µg/mL, comorbid with coronary heart disease, need for NIMV and CURB-65 ≥ 3 were mortality risk factors in CAP patients comorbid with COPD.

Comprehensive genomic analysis of the CNGC gene family in Brassica oleracea: novel insights into synteny, structures, and transcript profiles.

BACKGROUND: The cyclic nucleotide-gated ion channel (CNGC) family affects the uptake of cations, growth, pathogen defence, and thermotolerance in plants. However, the systematic identification, origin and function of this gene family has not been performed in Brassica oleracea, an important vegetable crop and genomic model organism. RESULTS: In present study, we identified 26 CNGC genes in B. oleracea genome, which are non-randomly localized on eight chromosomes, and classified into four major (I-IV) and two sub-groups (i.e., IV-a and IV-b). The BoCNGC family is asymmetrically fractioned into the following three sub-genomes: least fractionated (14 genes), most fractionated-I (10), and most fractionated-II (2). The syntenic map of BoCNGC genes exhibited strong relationships with the model Arabidopsis thaliana and B. rapa CNGC genes and provided markers for defining the regions of conserved synteny among the three genomes. Both whole-genome triplication along with segmental and tandem duplications contributed to the expansion of this gene family. We predicted the characteristics of BoCNGCs regarding exon-intron organisations, motif compositions and post-translational modifications, which diversified their structures and functions. Using orthologous Arabidopsis CNGCs as a reference, we found that most CNGCs were associated with various protein-protein interaction networks involving CNGCs and other signalling and stress related proteins. We revealed that five microRNAs (i.e., bol-miR5021, bol-miR838d, bol-miR414b, bol-miR4234, and bol-miR_new2) have target sites in nine BoCNGC genes. The BoCNGC genes were differentially expressed in seven B. oleracea tissues including leaf, stem, callus, silique, bud, root and flower. The transcript abundance levels quantified by qRT-PCR assays revealed that BoCNGC genes from phylogenetic Groups I and IV were particularly sensitive to cold stress and infections with bacterial pathogen Xanthomonas campestris pv. campestris, suggesting their importance in abiotic and biotic stress responses. CONCLUSION: Our comprehensive genome-wide analysis represents a rich data resource for studying new plant gene families. Our data may also be useful for breeding new B. oleracea cultivars with improved productivity, quality, and stress resistance.

Treatment and outcomes of tumor-induced osteomalacia associated with phosphaturic mesenchymal tumors: retrospective review of 12 patients.

BACKGROUND: Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome characterized by severe hypophosphatemia and osteomalacia. Nonspecific symptoms make the diagnosis elusive. In addition, locating the responsible tumor(s) is challenging. The aim of this study was to investigate the clinical management and outcomes of TIO. METHODS: The clinical features, diagnostic procedures, treatment, and outcomes of 12 patients were reviewed retrospectively. RESULTS: The cohort comprised six men and six women (mean age 45.5 ± 9.9 years, range 23-61 years). The mean duration of disease was 3.7 ± 2.6 years. All patients manifested progressive bone pain, muscle weakness, and/or difficulty walking. Serum phosphorus concentrations were low in all patients (mean 0.42 ± 0.12 mmol/L). Technetium-99m octreotide scintigraphy was performed in 11 patients and showed lesions in the right distal femur, left femoral head, and right tibial plateau, respectively, in three patients. Magnetic resonance imaging (MRI) was negative for lesions in one patient. Two patients underwent biopsies that showed negative histopathology. Two patients, at 2 years and 8 months, respectively, after having negative technetium-99m octreotide studies, underwent 18F-fluorodeoxyglucose positron emission tomography/computed tomography (CT), which revealed lesions in the sacrum and soft tissue of the left palm, respectively. One tumor was detected by CT and MRI. Overall, lesion sites were the head (two patients, 16.7%), thoracic and lumbar region (two, 16.7%), pelvis (three, 25%), lower limbs (four, 33.3%), and upper limbs (one, 8.3%). All patients underwent surgery, and histopathology showed phosphaturic mesenchymal tumors in each. Postoperatively, serum phosphorus concentrations normalized within 2-7 days in 11 patients. With follow-ups of 1-41 months, surgery was effective in 10 patients. One patient developed local recurrence and another had metastases. CONCLUSIONS: Locating tumors responsible for tumor-induced osteomalacia is often challenging. Although complete tumor resection confers a good prognosis in most patients, surveillance for recurrence and metastasis is necessary. Before surgery or when surgery is not indicated, oral phosphate can alleviate symptoms and metabolic imbalance.

Retrospective analysis of population-based causes of death and life expectancy in urban Western China from 2003 to 2012.

BACKGROUND: Hitherto, a population-based analysis of the cause of death in urban areas of Western China has not been undertaken over an extended period. The aims of this study were to calculate the overall and annual cause-specific mortality rates by age and sex in urban areas of Western China from 2003 to 2012 and to evaluate the quality of the data. METHODS: We used Excel software, cause-of-death registrations, and International Classification of Diseases, 10th revision, codes to calculate the overall and yearly cause-specific crude mortality rates by age and sex, the Chinese age-standardized mortality rate, and life expectancies. RESULTS: In the Jiulongpo District from 2003 to 2012, there was an increase in the number of death case reports in the census-registered population, a decrease in the number of omitted deaths, and rise in the crude mortality rate. Except for 2003, the Chinese age-standardized mortality rate was the lowest in 2012 (330.83/100,000) and highest in 2005 (390.08/100,000). Life expectancy increased from 78.36 years in 2005 to 81.67 years in 2012. CONCLUSIONS: With the development of its social economy, the Chinese government and public attach greater importance to cause-of-death surveillance. The quality of cause-of-death registrations has gradually increased, crude mortality rates have risen, the Chinese age-standardized mortality rate has fallen, and life expectancies have increased.

Development and molecular characterization of a doubled haploid population derived from a hybrid between japonica rice and wide compatible indica rice.

Doubled haploid (DH) populations, particularly those from subspecies crosses possessing the wide compatible gene S5n , are important germplasm resources for rice genetic studies and breeding, but their feature and potential have not been fully assessed and explored. In the present study, we produced a DH population from the hybrid of japonica 668B and wide compatible indica T23. Genotyping of the S5 locus with allele-specific markers for ORF3, ORF4 and ORF5 revealed a potential recombination hot spot in the ORF3-ORF4 region. Haplotyping analysis revealed that 21/34 subspecies specific Indel markers segregated in distortion in the DH population, with a few lines having indica alleles either extremely low (1.7%) or high (98.3%), with little effect of the S5 allele. While DH lines with the S5n allele had higher frequency of indica alleles, no effect of the S5n allele was observed on all agronomic traits but flowering time. Taken together, the present study advanced understanding of the genetics of wide crosses in general, and DH production in particular between the two rice subspecies, and the new DH population generated will become a useful resource for rice genetic study and breeding in the future.

Cyclic nucleotide-gated ion channel gene family in rice, identification, characterization and experimental analysis of expression response to plant hormones, biotic and abiotic stresses.

BACKGROUND: Cyclic nucleotide-gated channels (CNGCs) are Ca2+-permeable cation transport channels, which are present in both animal and plant systems. They have been implicated in the uptake of both essential and toxic cations, Ca2+ signaling, pathogen defense, and thermotolerance in plants. To date there has not been a genome-wide overview of the CNGC gene family in any economically important crop, including rice (Oryza sativa L.). There is an urgent need for a thorough genome-wide analysis and experimental verification of this gene family in rice. RESULTS: In this study, a total of 16 full length rice CNGC genes distributed on chromosomes 1-6, 9 and 12, were identified by employing comprehensive bioinformatics analyses. Based on phylogeny, the family of OsCNGCs was classified into four major groups (I-IV) and two sub-groups (IV-A and IV- B). Likewise, the CNGCs from all plant lineages clustered into four groups (I-IV), where group II was conserved in all land plants. Gene duplication analysis revealed that both chromosomal segmentation (OsCNGC1 and 2, 10 and 11, 15 and 16) and tandem duplications (OsCNGC1 and 2) significantly contributed to the expansion of this gene family. Motif composition and protein sequence analysis revealed that the CNGC specific domain "cyclic nucleotide-binding domain (CNBD)" comprises a "phosphate binding cassette" (PBC) and a "hinge" region that is highly conserved among the OsCNGCs. In addition, OsCNGC proteins also contain various other functional motifs and post-translational modification sites. We successively built a stringent motif: (LI-X(2)-[GS]-X-[FV]-X-G-[1]-ELL-X-W-X(12,22)-SA-X(2)-T-X(7)-[EQ]-AF-X-L) that recognizes the rice CNGCs specifically. Prediction of cis-acting regulatory elements in 5' upstream sequences and expression analyses through quantitative qPCR demonstrated that OsCNGC genes were highly responsive to multiple stimuli including hormonal (abscisic acid, indoleacetic acid, kinetin and ethylene), biotic (Pseudomonas fuscovaginae and Xanthomonas oryzae pv. oryzae) and abiotic (cold) stress. CONCLUSIONS: There are 16 CNGC genes in rice, which were probably expanded through chromosomal segmentation and tandem duplications and comprise a PBC and a "hinge" region in the CNBD domain, featured by a stringent motif. The various cis-acting regulatory elements in the upstream sequences may be responsible for responding to multiple stimuli, including hormonal, biotic and abiotic stresses.

A down-regulated epi-allele of the genomes uncoupled 4 gene generates a xantha marker trait in rice.

KEY MESSAGE: A γ-ray-induced xantha trait is epigenetically controlled by the genomes uncoupled 4 gene with enhanced promoter segment methylation and down-regulated expression in rice. For easy testing and to increase varietal purity, a xantha mutation (xnt), which turns plants yellow and makes them visually distinguishable from normal green rice, has been generated and bred into male sterile lines for hybrid rice production. The xnt locus was previously fine mapped to a ~100-kb interval on chromosome 11, but its identity was unknown. In this study, xnt was further narrowed down to a 57-kb fragment carrying eight opening reading frames (ORFs). All eight ORFs had identical genomic sequences and all but ORF2 (g enomes uncoupled 4, OsGUN4) had similar transcript abundance in the xantha mutant Huangyu B (HYB) and its parental variety Longtefu B (LTB). The expression of OsGUN4, however, was significantly reduced in HYB compared with LTB in terms of both transcript abundance (0.2% that of LTB) and expressed protein level (barely detectable in HYB but greater than the heat shock protein reference in LTB). Therefore, OsGUN4 was identified as the candidate gene underlying the xantha trait. The function of OsGUN4 in the xantha phenotype was confirmed by identification and characterization of new allelic OsGUN4 mutations. Comparative bisulfite genomic sequencing of OsGUN4 revealed increased methylation in a promoter region in the mutant, and the correlation between increased methylation and the xantha phenotype was further verified by demethylation treatment. In summary, we have identified an epi-allele of OsGUN4 as the causal gene of the xantha marker trait and revealed that enhanced methylation in its promoter down-regulated its expression in rice.

Seed-specific silencing of OsMRP5 reduces seed phytic acid and weight in rice.

Phytic acid (PA) is poorly digested by humans and monogastric animals and negatively affects human/animal nutrition and the environment. Rice mutants with reduced PA content have been developed but are often associated with reduced seed weight and viability, lacking breeding value. In the present study, a new approach was explored to reduce seed PA while attaining competitive yield. The OsMRP5 gene, of which mutations are known to reduce seed PA as well as seed yield and viability, was down-regulated specifically in rice seeds by using an artificial microRNA driven by the rice seed specific promoter Ole18. Seed PA contents were reduced by 35.8-71.9% in brown rice grains of transgenic plants compared to their respective null plants (non-transgenic plants derived from the same event). No consistent significant differences of plant height or number of tillers per plant were observed, but significantly lower seed weights (up to 17.8% reduction) were detected in all transgenic lines compared to null plants, accompanied by reductions of seed germination and seedling emergence. It was observed that the silencing of the OsMRP5 gene increased the inorganic P (Pi) levels (up to 7.5 times) in amounts more than the reduction of PA-P in brown rice. This indicates a reduction in P content in other cellular compounds, such as lipids and nucleic acids, which may affect overall seed development. Put together, the present study demonstrated that seed specific silencing of OsMRP5 could significantly reduce the PA content and increase Pi levels in seeds; however, it also significantly lowers seed weight in rice. Discussions were made regarding future directions towards producing agronomically competitive and nutritionally valuable low PA rice.

Synthesis and the hepatoprotective activity of dibenzocyclooctadiene lignan derivatives.

The halogenated and oxidized derivatives (1a-1e, 1a'-1c', 2a-2d, 2a'-2b', 3a-3e, 3' and 3a'-3b') of schizandrin (1), schizandrin B (2) and schisanhenol (3) were synthesized. The hepatoprotective effects of these dibenzocyclooctadiene lignan analogues against CCl4-induced injury were preliminarily evaluated. Most of the analogues exhibited higher protective effects than the positive control biphenyldicarboxylate (DDB). Among these active analogues, dichloroschisanhenol (3a) exhibited the strongest protective activity (cell survival rate exceeding 98.0%).

Using Quercetin to Construct Molecularly Imprinting Polymer in the Preparation and Enrichment of Flavonol and Flavonoid Compounds.

Flavonol and flavonoid compounds are important natural compounds with various biomedical activities. Therefore, it is of great significance to develop a strategy for the specific extraction of flavonol and flavonoid compounds. Quercetin is a well-studied flavonoid possessing many health benefits. This compound is a versatile antioxidant known to possess protective abilities against body tissue injury induced by pathological situations and various drug toxicities. Although quercetin is widely distributed in many plants, its content generally is not very high. Therefore, the specific extraction of quercetin as well as other flavonol and flavonoid compounds has profound significance. In this work, the quercetin molecularly imprinting polymer (QMIP) was successfully prepared, in which a typical flavonol quercetin was selected as the template molecule. QMIP was synthesized by performing the surface molecular imprinting technology on the surface of NH2-MIL-101(Fe). Our study results showed that QMIP exhibited quick binding kinetic behavior, a high adsorption capacity (57.04[Formula: see text]mg/g), and the specific recognition ability toward quercetin compared with structurally distinct compounds (selective [Formula: see text]). The specific adsorption ability of quercetin by QMIP was further explained using computation simulation that molecules with non-planar 3D conformations hardly entered the molecularly imprinted cavities on QMIP. Finally, QMIP was successfully used for the specific extraction of quercetin and five other flavonol and flavonoid compounds in the crude extracts from Sapium sebiferum. This study proposes a new strategy to synthesize the molecularly imprinted polymer based on a single template for enriching and loading a certain class of active ingredients with similar core structures from variable botanicals.

Characterization of OsMIK in a rice mutant with reduced phytate content reveals an insertion of a rearranged retrotransposon.

The rice low phytic acid (lpa) mutant Os-lpa-XS110-1(XS-lpa) has ~45 % reduction in seed phytic acid (PA) compared with the wild-type cultivar Xiushui 110. Previously, a single recessive gene mutation was shown to be responsible for the lpa phenotype and was mapped to a region of chromosome 3 near OsMIK (LOC_Os03g52760) and OsIPK1 (LOC_Os03g51610), two genes involved in PA biosynthesis. Here, we report the identification of a large insert in the intron of OsMIK in the XS-lpa mutant. Sequencing of fragments amplified through TAIL-PCRs revealed that the insert was a derivative of the LINE retrotransposon gene LOC_Os03g56910. Further analyses revealed the following characteristics of the insert and its impacts: (1) the inserted sequence of LOC_Os03g56910 was split at its third exon and rejoined inversely, with its 5' and 3' flanking sequences inward and the split third exon segments outward; (2) the LOC_Os03g56910 remained in its original locus in XS-lpa, and the insertion probably resulted from homologous recombination repair of a DNA double strand break; (3) while the OsMIK transcripts of XS-lpa and Xiushui 110 were identical, substantial reductions of the transcript abundance (~87 %) and the protein level (~60 %) were observed in XS-lpa, probably due to increased methylation in its promoter region. The above findings are discussed in the context of plant mutagenesis, epigenetics and lpa breeding.