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To better obtain protein–flavonoid complexes owned more powerful functions, non-covalent complexes between β-lactoglobulin (β-LG) and baicalein/p-coumaric acid/polydatin (Bai/p-CA/PD) were investigated. The properties of these complexes were investigated using ultraviolet (UV)-visible spectra, circular dichroism (CD) spectra, Fourier-transform infrared (FTIR), etc.; the non-covalent complexes' parameters were evaluated using fluorescence spectra and molecular docking. The peaks shifted in UV, and α-helix decreased in CD, confirming the formation of the complexes. The blue shift of amide bands and -OH peaks in FTIR indicated that the hydrophobic interactions and hydrogen bonds were strengthened. Differential scanning calorimetry (DSC) indicates that β-LG-Bai had heat resistance (improved melting peak: 188.8 °C to 195.8 °C). ABTS assay showed synergistic effects of β-LG-Bai (76.7% [β-LG-Bai] > 70.6% [β-LG + Bai], 50 μmol/L). Bai had a higher quenching ability (70.81%) than p-CA (38.69%) and PD (40.95%). The affinity order was Bai > PD > p-CA, and molecular docking binding energy (-6.02 [Bai], -5.39 [p-CA], and -5.4 kcal/mol [PD]) verified the affinity relationship. The binding constants increased with increasing temperature (2.166, 4.581, and 5.741, × 105 L/mol, for 298, 308, and 318 K, respectively), indicating that a higher temperature promoted stabilization of β-LG-Bai, which is consistent with hydrophobic interactions in molecular docking being the driving force of the β-LG-Bai complexes. The β-LG-Bai non-covalent complexes own synergistic antioxidant effects and improved high-temperature stability characteristics, which may have promising applications in functional foods. [ABSTRACT FROM AUTHOR]

In the age of big data, recipe recommendation is of great significance. It can recommend recipes in line with the user's eating habits in massive data. Compared with other recommendation tasks, recipe recommendation is influenced by multiple aspects and requires fine-grained learning to obtain entity representations. Therefore, the traditional recommendation method cannot meet people's requirements. In this paper, we propose the Collaborative Knowledge Propagation Graph Attention Network for Recipes Recommendation (CGRS). This method designs collaborative information propagation to make full use of user interaction and recipe attribute information to meet the needs of multiple influencing factors. Use the graph attention feature learning network to obtain the high-order feature information of the entity to meet the demand for fine-grained representation. Specifically, the method first obtains the multi-hop triplet sets of users and recipes through a collaborative message propagation strategy. Then utilises a graph attention feature learning layer to learn the topological proximity structure features of the triplet sets. Obtain high-level semantic information of entities by superimposing network layers. Design an attention aggregator at the prediction layer to refine the embedding representation of entities. Finally predict the user-recipe interaction probability. Experimental results prove the advancement and effectiveness of CGRS. [ABSTRACT FROM AUTHOR]

Aluminum (Al) toxicity and low pH are major factors limiting plant growth in acidic soils. Sensitive to Proton Rhizotoxicity 1 (STOP1) transcription factors respond to these stresses by regulating the expression of multiple Al- or low pH-responsive genes. ZmSTOP1-A, a STOP1-like protein from maize (Zea mays), was localized to the nucleus and showed transactivation activity. ZmSTOP1-A was expressed moderately in both roots and shoots of maize seedlings, but was not induced by Al stress or low pH. Overexpression of ZmSTOP1-A in Arabidopsis Atstop1 mutant partially restored Al tolerance and improved low pH tolerance with respect to root growth. Regarding Al tolerance, ZmSTOP1-A/Atstop1 plants showed clear upregulation of organic acid transporter genes, leading to increased organic acid secretion and reduced Al accumulation in roots. In addition, the antioxidant enzyme activity in roots and shoots of ZmSTOP1-A/Atstop1 plants was significantly enhanced, ultimately alleviating Al toxicity via scavenging reactive oxygen species. Similarly, ZmSTOP1-A could directly activate ZmMATE1 expression in maize, positively correlated with the number of Al-responsive GGNVS cis-elements in the ZmMATE1 promoter. Our results reveal that ZmSTOP1-A is an important transcription factor conferring Al tolerance by enhancing organic acid secretion and reactive oxygen species scavenging in Arabidopsis. [ABSTRACT FROM AUTHOR]

Owing to the heterogeneity and incomplete information present in various domain knowledge graphs, the alignment of distinct source entities that represent an identical real-world entity becomes imperative. Existing methods focus on cross-lingual knowledge graph alignment, and assume that the entities of knowledge graphs in the same language are unique. However, due to the ambiguity of language, heterogeneous knowledge graphs in the same language are often duplicated, and relationship triples are far less than those of cross-lingual knowledge graphs. Moreover, existing methods rarely exclude noisy entities in the process of alignment. These make it impossible for existing methods to deal effectively with the entity alignment of domain knowledge graphs. In order to address these issues, we propose a novel entity alignment approach based on domain-oriented embedded representation (DomainEA). Firstly, a filtering mechanism employs the language model to extract the semantic features of entities and to exclude noisy entities for each entity. Secondly, a Structural Aggregator (SA) incorporates multiple hidden layers to generate high-order neighborhood-aware embeddings of entities that have few relationship connections. An Attribute Aggregator (AA) introduces self-attention to dynamically calculate weights that represent the importance of the attribute values of the entities. Finally, the approach calculates a transformation matrix to map the embeddings of distinct domain knowledge graphs onto a unified space, and matches entities via the joint embeddings of the SA and AA. Compared to six state-of-the-art methods, our experimental results on multiple food datasets show the following: (i) Our approach achieves an average improvement of 6.9% on MRR. (ii) The size of the dataset has a subtle influence on our approach; there is a positive correlation between the expansion of the dataset size and an improvement in most of the metrics. (iii) We can achieve a significant improvement in the level of recall by employing a filtering mechanism that is limited to the top-100 nearest entities as the candidate pairs. [ABSTRACT FROM AUTHOR]

This study investigated the effect of frequently used analgesics in cancer pain management (flurbiprofen (FLU), tramadol (TRA), and morphine (MOR)) and a novel α2-adrenergic agonist (dexmedetomidine, DEX) on temozolomide (TMZ) sensitivity in glioma cells. Cell counting kit-8 and colony-formation assays were performed to analyze the viability of U87 and SHG-44 cell lines. A high and low cell density of colony method, pharmacological methods, and connexin43 mimetic peptide GAP27 were used to manipulate the function of gap junctions; "Parachute" dye coupling and western blot were employed to determine junctional channel transfer ability and connexin expression. The results showed that DEX (in the concentration range of 0.1 to 5.0 ng/ml) and TRA (in the concentration range of 1.0 to 10.0 µg/ml) reduced the TMZ cytotoxicity in a concentration-dependent manner but was only observed with high cell density (having formed gap junction). The cell viability percentage was 71.3 to 86.8% when DEX was applied at 5.0 ng/ml, while tramadol showed 69.6 to 83.7% viability at 5.0 μg/ml in U87 cells. Similarly, 5.0 ng/ml of DEX resulted in 62.6 to 80.5%, and 5.0 μg/ml TRA showed 63.5 to 77.3% viability in SHG-44 cells. Further investigating the impact of analgesics on gap junctions, only DEX and TRA were found to decrease channel dye transfer through connexin phosphorylation and ERK pathway, while no such effect was observed for FLU and MOR. Analgesics that can affect junctional communication may compromise the effectiveness of TMZ when used simultaneously. [ABSTRACT FROM AUTHOR]

Key message: Combined GWAS, WGCNA, and gene-based association studies identified the co-expression network and hub genes for maize EC induction. ZmARF23 bound to ZmSAUR15 promoter and regulated its expression, affecting EC induction. Embryonic callus (EC) induction in immature maize embryos shows high genotype dependence, which limits the application of genetic transformation in transgenic breeding and gene function elucidation in maize. Herein, we conducted a genome-wide association mapping (GWAS) for four EC induction-related traits, namely rate of embryonic callus induction (REC), increased callus diameter (ICD), ratio of shoot formation (RSF), and length of shoot (LS) across different environments. A total of 77 SNPs were significantly associated these traits under three environments and using the averages (across environments). Among these significant SNPs, five were simultaneously detected under multiple environments and 11 had respective phenotypic variation explained > 10%. A total of 257 genes were located in the linkage disequilibrium decay of these REC- and ICD-associated SNPs, of which 178 were responsive to EC induction. According to the expression values of the 178 genes, we performed a weighted gene co-expression network analysis (WGCNA) and revealed an EC induction-associated module and five hub genes. Hub gene-based association studies uncovered that the intragenic variations in GRMZM2G105473 and ZmARF23 influenced EC induction efficiency among different maize lines. Dual-luciferase reporter assay indicated that ZmARF23 bound to the promoter of a known causal gene (ZmSAUR15) for EC induction and positively regulated its expression on the transcription level. Our study will deepen the understanding of genetic and molecular mechanisms underlying EC induction and contribute to the use of genetic transformation in maize. [ABSTRACT FROM AUTHOR]

In the age of big data, recipe recommendation is of great significance. It can recommend recipes in line with the user's eating habits in massive data. Compared with other recommendation tasks, recipe recommendation is influenced by multiple aspects and requires fine-grained learning to obtain entity representations. Therefore, the traditional recommendation method cannot meet people's requirements. In this paper, we propose the Collaborative Knowledge Propagation Graph Attention Network for Recipes Recommendation (CGRS). This method designs collaborative information propagation to make full use of user interaction and recipe attribute information to meet the needs of multiple influencing factors. Use the graph attention feature learning network to obtain the high-order feature information of the entity to meet the demand for fine-grained representation. Specifically, the method first obtains the multi-hop triplet sets of users and recipes through a collaborative message propagation strategy. Then utilises a graph attention feature learning layer to learn the topological proximity structure features of the triplet sets. Obtain high-level semantic information of entities by superimposing network layers. Design an attention aggregator at the prediction layer to refine the embedding representation of entities. Finally predict the user-recipe interaction probability. Experimental results prove the advancement and effectiveness of CGRS. [ABSTRACT FROM AUTHOR]

Personalized recipe recommendation is attracting more and more attention, which can help people make choices from the exploding growth of online food information. Unlike other recommendation tasks, the target of recipe recommendation is a non-atomic item, so attribute information is especially important for the representation of recipes. However, traditional collaborative filtering or content-based recipe recommendation methods tend to focus more on user–recipe interaction information and ignore higher-order semantic and structural information. Recently, graph neural networks (GNNs)-based recommendation methods provided new ideas for recipe recommendation, but there was a problem of sparsity of supervised signals caused by the long-tailed distribution of heterogeneous graph entities. How to construct high-quality representations of users and recipes becomes a new challenge for personalized recipe recommendation. In this paper, we propose a new method, a multi-level knowledge-aware contrastive learning network (MKCLN) for personalized recipe recommendation. Compared with traditional comparative learning, we design a multi-level view to satisfy the requirement of fine-grained representation of users and recipes, and use multiple knowledge-aware aggregation methods for node fusion to finally make recommendations. Specifically, the local-level includes two views, interaction view and semantic view, which mine collaborative information and semantic information for high-quality representation of nodes. The global-level learns node embedding by capturing higher-order structural information and semantic information through a network structure view. Then, a kind of self-supervised cross-view contrastive learning is invoked to make the information of multiple views collaboratively supervise each other to learn fine-grained node embeddings. Finally, the recipes that satisfy personalized preferences are recommended to users by joint training and model prediction functions. In this study, we conduct experiments on two real recipe datasets, and the experimental results demonstrate the effectiveness and advancement of MKCLN. [ABSTRACT FROM AUTHOR]

With the advent of the era of rapid information expansion, the massive data backlog that exists on the Internet has led to a serious information overload problem, which makes recommendation systems a crucial part of human life. In particular, the Point-Of-Interest (POI) recommendation system has been applied to many real-life scenarios, such as life services and autonomous driving. Specifically, the goal of POI recommendation is to recommend locations that match their personalized preferences to users. In existing POI recommendation methods, people tend to pay more attention to the impact of temporal and spatial factors of POI on users, which will alleviate the problems of data sparsity and cold start in POI recommendation. However, this tends to ignore the differences among individual users, and considering only temporal and spatial attributes does not support fine-grained POI recommendations. To solve this problem, we propose a new Fine-grained POI Recommendation With Multi-Graph Convolutional Network (FP-MGCN). This model focuses on the content representation of POIs, captures users' personalized preferences using semantic information from user comments, and learns fine-grained representations of users and POIs through the relationships between content–content, content–POI, and POI–user. FP-MGCN employs multiple embedded propagation layers and adopts information propagation mechanisms to model the higher-order connections of different POI-related relations for enhanced representation. Fine-grained POI is finally recommended to users through the three types of propagation we designed: content–content information propagation, content–POI information propagation, and POI–user information propagation. We have conducted detailed experiments on two datasets, and the results show that FP-MGCN has advanced performance and can alleviate the data sparsity problem in POI recommendation tasks. [ABSTRACT FROM AUTHOR]

Aluminum (Al) toxicity causes severe reduction in crop yields in acidic soil. The natural resistance-associated macrophage proteins (NRAMPs) play an important role in the transport of mineral elements in plants. Recently, OsNrat1 and SbNrat1 were reported specifically to transport trivalent Al ions. In this study, we functionally characterized ZmNRAMP4, a gene previously identified from RNA-Seq data from Al-treated maize roots, in response to Al exposure in maize. ZmNRAMP4 was predominantly expressed in root tips and was specifically induced by Al stress. Yeast cells expressing ZmNRAMP4 were hypersensitive to Al, which was associated with Al accumulation in yeast. Furthermore, overexpression of ZmNRAMP4 in Arabidopsis conferred transgenic plants with a significant increase in Al tolerance. However, expression of ZmNRAMP4, either in yeast or in Arabidopsis, had no effect on the response to cadmium stress. Taken together, these results underlined an internal tolerance mechanism involving ZmNRAMP4 to enhance Al tolerance via cytoplasmic sequestration of Al in maize. [ABSTRACT FROM AUTHOR]

With the vigorous development of blockchain technology represented by bitcoin, blockchain technology has gradually entered the stage of blockchain 3.0 characterized by "programmable society". And the application of blockchain technology in all walks of life has achieved actual results. Blockchain technology has typical characteristics of decentralization, Tamper-resistant data, information openness and transparency, and natural fit with the application requirements in the field of certificate tracing, which makes the development of the applications of blockchain deposit and traceability in full swing. First, this paper describes the concept, application process, key technology of blockchain deposit and traceability, the three application architectures of blockchain deposit and traceability, and the overall architecture of its system. Then, it introduces the application of scenarios and the blockchain deposit and traceability in various fields. Next, it discusses the issues existing in the development of the application of blockchain deposit and traceability. Finally, the paper also expresses the best wishes for the future of its application. [ABSTRACT FROM AUTHOR]

Background: Long noncoding RNAs (lncRNAs) play important roles in essential biological processes. However, our understanding of lncRNAs as competing endogenous RNAs (ceRNAs) and their responses to nitrogen stress is still limited. Results: Here, we surveyed the lncRNAs and miRNAs in maize inbred line P178 leaves and roots at the seedling stage under high-nitrogen (HN) and low-nitrogen (LN) conditions using lncRNA-Seq and small RNA-Seq. A total of 894 differentially expressed lncRNAs and 38 different miRNAs were identified. Co-expression analysis found that two lncRNAs and four lncRNA-targets could competitively combine with ZmmiR159 and ZmmiR164, respectively. To dissect the genetic regulatory by which lncRNAs might enable adaptation to limited nitrogen availability, an association mapping panel containing a high-density single–nucleotide polymorphism (SNP) array (56,110 SNPs) combined with variable LN tolerant-related phenotypes obtained from hydroponics was used for a genome-wide association study (GWAS). By combining GWAS and RNA-Seq, 170 differently expressed lncRNAs within the range of significant markers were screened. Moreover, 40 consistently LN-responsive genes including those involved in glutamine biosynthesis and nitrogen acquisition in root were identified. Transient expression assays in Nicotiana benthamiana demonstrated that LNC_002923 could inhabit ZmmiR159-guided cleavage of Zm00001d015521. Conclusions: These lncRNAs containing trait-associated significant SNPs could consider to be related to root development and nutrient utilization. Taken together, the results of our study can provide new insights into the potential regulatory roles of lncRNAs in response to LN stress, and give valuable information for further screening of candidates as well as the improvement of maize resistance to LN stress. [ABSTRACT FROM AUTHOR]

Aluminum (Al) toxicity is the primary limiting factor that affects crop yields in acid soil. However, the genes that contribute to the Al tolerance process in maize are still poorly understood. Previous studies have predicted that ZmAT6 is a novel protein which could be upregulated under Al stress condition. Here, we found that ZmAT6 is expressed in many tissues and organs and can be dramatically induced by Al in both the roots and shoots but particularly in the shoots. The overexpression of ZmAT6 in maize and Arabidopsis plants increased their root growth and reduced the accumulation of Al, suggesting the contribution of ZmAT6 to Al tolerance. Moreover, the ZmAT6 transgenic maize plants had lower contents of malondialdehyde and reactive oxygen species (ROS), but much higher proline content and even lower Evans blue absorption in the roots compared with the wild type. Furthermore, the activity of several enzymes of the antioxidant system, such as peroxidase (POD), superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX), increased in ZmAT6 transgenic maize plants, particularly SOD. Consistently, the expression of ZmSOD in transgenic maize was predominant upregulated by Al stress. Taken together, these findings revealed that ZmAT6 could at least partially confer enhanced tolerance to Al toxicity by scavenging ROS in maize. [ABSTRACT FROM AUTHOR]

SUMMARY: Inorganic phosphorus (Pi) is an essential element in numerous metabolic reactions and signaling pathways, but the molecular details of these pathways remain largely unknown. In this study, metabolite profiles of maize (Zea mays L.) leaves and roots were compared between six low‐Pi‐sensitive lines and six low‐Pi‐tolerant lines under Pi‐sufficient and Pi‐deficient conditions to identify pathways and genes associated with the low‐Pi stress response. Results showed that under Pi deprivation the concentrations of nucleic acids, organic acids and sugars were increased, but that the concentrations of phosphorylated metabolites, certain amino acids, lipid metabolites and nitrogenous compounds were decreased. The levels of secondary metabolites involved in plant immune reactions, including benzoxazinoids and flavonoids, were significantly different in plants grown under Pi‐deficient conditions. Among them, the 11 most stable metabolites showed significant differences under low‐ and normal‐Pi conditions based on the coefficient of variation (CV). Isoleucine and alanine were the most stable metabolites for the identification of Pi‐sensitive and Pi‐resistant maize inbred lines. With the significant correlation between morphological traits and metabolites, five low‐Pi‐responding consensus genes associated with morphological traits and simultaneously involved in metabolic pathways were mined by combining metabolites profiles and genome‐wide association study (GWAS). The consensus genes induced by Pi deficiency in maize seedlings were also validated by reverse‐transcription quantitative polymerase chain reaction (RT‐qPCR). Moreover, these genes were further validated in a recombinant inbred line (RIL) population, in which the glucose‐6‐phosphate‐1‐epimerase encoding gene mediated yield and correlated traits to phosphorus availability. Together, our results provide a framework for understanding the metabolic processes underlying Pi‐deficient responses and give multiple insights into improving the efficiency of Pi use in maize. Significance statement: Metabolite profiling and GWAS were applied to reveal maize low‐Pi response mechanisms. [ABSTRACT FROM AUTHOR]

Copper (Cu) is an essential micronutrient for plant growth and development; Cu homeostasis in plant is maintained by the important functions of Ctr/COPT-type Cu transporters. Although the COPT genes have been identified in Arabidopsis thaliana and rice, little is known about Cu transporters in maize. In this study, three-members of putative maize Cu transporters (ZmCOPT 1, 2 and 3) are identified. ZmCOPT genes have expression in all of the tested tissues, including roots, stems, leaves and flowers (male and female), and their expression levels vary responding to stress due to Cu-deficiency and excess. Functional complementation and overexpression together with Cu uptake measurements in ZmCOPTs-transformed ctr1⊿ctr2⊿mutant strain or the wild type strain of Saccharomyces cerevisiae show that the three ZmCOPT members possess the ability to be Cu transporters. Among these, ZmCOPT1 and ZmCOPT2 have high-affinity while ZmCOPT3 has low-affinity. In addition, ZmCOPT2 tend to specifically transport Cu (I) but no other bivalent metal ions. [ABSTRACT FROM AUTHOR]

Key message: ZmMGT10 was specifically expressed in maize roots and induced by a deficiency of magnesium. Overexpression of ZmMGT10 restored growth deficiency of the Salmonella typhimurium MM281 strain and enhanced the tolerance in Arabidopsis to stress induced by low magnesium levels by increasing uptake of Mg via roots. Abstract: CorA/MRS2/MGT-type Mg transporters play a significant role in maintaining magnesium (Mg) homeostasis in plants. Although the maize CorA/MRS2/MGT family comprises of 12 members, currently no member has been functionally characterized. Here, we report the isolation and functional characterization of ZmMGT10 from the maize MRS2/MGT gene family. ZmMGT10 has a typical structure feature which includes two conserved TMs near the C-terminal end and an altered AMN tripeptide motif. The high sequence similarity and close phylogenetic relationship indicates that ZmMGT10 is probably the counterpart of Arabidopsis AtMGT6. The complementation of the Salmonella typhimurium mutated MM281 strain indicates that ZmMGT10 possesses the ability to transport Mg. ZmMGT10 was specifically expressed in the plant roots and it can be stimulated by a deficiency of Mg. Transgenic Arabidopsis plants which overexpressed ZmMGT10 grew more vigorously than wild-type plants under low Mg conditions, exhibited by longer root length, higher plant fresh weight and chlorophyll content, suggesting ZmMGT10 was essential for plant growth and development under low Mg conditions. Further investigations found that high accumulation of Mg occurred in transgenic plants attributed to improved Mg uptake and thereby enhanced tolerance to Mg deficiency. Results from this investigation illustrate that ZmMGT10 is a Mg transporter of maize which can enhance the tolerance to Mg deficient conditions by improving Mg uptake in the transgenic plants of Arabidopsis. [ABSTRACT FROM AUTHOR]

Mirabilis jalapa L is the most commonly grown ornamental species of Mirabilis and is available in a range of brilliant colors. However, genetic research on Mirabilis jalapa L is limited. Using fluorescent differential display (FDD) screening, we report the identification of a novel Ty1-copia-like retrotransposon in the genome of the red flower of Mirabilis jalapa L, and we named it REC66 based on its sequence homology to the GAG protein from Ty1-copia retrotransposon. Using degenerate primers based on the DNA sequence of REC66, a total of fourteen different variants in reverse transcriptase (RT) sequence were recovered from the genomic DNA. These RT sequences show a high degree of heterogeneity characterized mainly by deletion mutation; they can be divided into three subfamilies, of which the majority encode defective RT. This is the first report of a Ty1-copia retrotransposon in Mirabilis jalapa L. The finding could be helpful for the development of new molecular markers for genetic studies, particularly on the origin and evolutionary relationships of M. jalapa L, and the study of Ty1-copia retrotransposons and plant genome evolution in the genus Mirabilis or family Nyctaginaceae. [ABSTRACT FROM AUTHOR]

Gro/Tup1 proteins act as negative transcriptional regulators and play crucial roles in many growth and developmental processes in a wide range of organisms. However, our understanding of Gro/Tup1 protein functions in plants is confined to the model plant Arabidopsis. Here, 11 Gro/Tup1 genes, which were characterized by the typical LisH and WD40 repeat domains, were identified in maize through a genome-wide survey. A phylogenetic analysis revealed that maize Gro/Tup1 proteins could be divided into three subfamilies, in which members shared similar protein and gene structures. The predicted maize Gro/Tup1 genes were distributed on seven chromosomes and segmental duplication contributed to their expansion. Many predicted cis-elements associated with hormones, biotic- or abioticstress responses, meristem and seed development, and circadian rhythms, were found in their putative promoter regions. A potential associated protein analysis identified a large number of candidates, including transcription factors, chromatin-modifying enzymes, protein kinases, and ubiquitinconjugating enzymes. An expression profile derived from the RNA-seq data indicated that Gro/Tup1 genes in maize were widely expressed in various organs and tissues. Quantitative real-time PCR revealed that these genes responded to at least one hormone or abiotic stress, either in roots or in shoots. Our study provides useful information on the Gro/Tup1 genes in maize and will facilitate the further functional validation of these genes in growth and development, hormone responses, and biotic- or abiotic-stress resistance. [ABSTRACT FROM AUTHOR]

C-type cytoplasmic male sterile (CMS-C) line plays an important role in hybrid seed production in maize. However, mechanisms of pollen abortion and fertility restoration remain unclear. This study aimed to investigate the mechanisms of CMS-C pollen abortion and fertility restoration, particularly based on epigenetics, and to understand the relationship between male fertility performance and DNA methylation status. Methylation-sensitive amplification polymorphism (MSAP) technique was conducted to analyze DNA methylation levels and patterns of tassels at pollen-mother cell, tetrad, mononuclear, and binuclear stages among four half-sib hybrids and their parents with different fertility. Results showed that DNA methylation levels in fertility restored hybrids were higher than those in sterility maintained hybrids. Nine CCGG sites, which displayed methylation polymorphism between male-fertile and male-sterile hybrids, were screened. To validate MSAP results, we performed methylation-sensitive PCR (MS-PCR) and found consistent observations in cloned methylation sites. Interestingly, a specific site named 16-1 was discovered in the region of Rf5 gene, which is one of the restorer genes of CMS-C. Thus, DNA methylation may participate in regulating the expression of fertility restorer genes of maize CMS-C. [ABSTRACT FROM AUTHOR]

Nitrogen (N) is the most important macronutrient for plant growth and development. Hence, understanding genetic architectures and functional genes involved in the response to N deficiency can greatly facilitate the development of low-N-tolerant cultivars. In this study, we collected 212 quantitative trait loci (QTL) of agronomically important traits under low-N stress conditions in maize. We then identified 21 consensus QTL (cQTL) strongly induced for low-N tolerance after excluding overlapping cQTL containing QTL simultaneously identified in meta-analyses of studies performed under other environmental conditions. Among the 21 cQTL, 30 candidate maize genes were identified from maize large-scale differential expression data derived from analyses of low-N stress, and the 12 most important maize orthologs were identified using homologous BLAST analyses of genes with known functions in N use efficiency in model plants. Furthermore, maize orthologs associated with low-N tolerance and metabolism were also predicted using large-scale expression data from other model plants. The present genetic loci and candidate genes indicate the molecular mechanisms of low-N tolerance in maize and may provide information for QTL fine mapping and molecular marker-assisted selection. [ABSTRACT FROM AUTHOR]

The reverse transcription quantitative polymerase chain reaction (RT-qPCR) is a powerful and widely used technique for the measurement of gene expression. Reference genes, which serve as endogenous controls ensure that the results are accurate and reproducible, are vital for data normalization. To bolster the literature on reference gene selection in maize, ten candidate reference genes, including eight traditionally used internal control genes and two potential candidate genes from our microarray datasets, were evaluated for expression level in maize across abiotic stresses (cold, heat, salinity, and PEG), phytohormone treatments (abscisic acid, salicylic acid, jasmonic acid, ethylene, and gibberellins), and different tissue types. Three analytical software packages, geNorm, NormFinder, and Bestkeeper, were used to assess the stability of reference gene expression. The results revealed that elongation factor 1 alpha (EF1α), tubulin beta (β-TUB), cyclophilin (CYP), and eukaryotic initiation factor 4A (EIF4A) were the most reliable reference genes for overall gene expression normalization in maize, while GRP (Glycine-rich RNA-binding protein), GLU1(beta-glucosidase), and UBQ9 (ubiquitin 9) were the least stable and most unsuitable genes. In addition, the suitability of EF1α, β-TUB, and their combination as reference genes was confirmed by validating the expression of WRKY50 in various samples. The current study indicates the appropriate reference genes for the urgent requirement of gene expression normalization in maize across certain abiotic stresses, hormones, and tissue types. [ABSTRACT FROM AUTHOR]

In the present study, a mutated chimericorf364, namedorf366-c, was identified in a maize C type cytoplasmic male sterile line (CMS-C) by PCR and RT-PCR. Four base pair adjacent base substitution mutations (CAAA to TTTT) and eight bp insertion mutations were found inorf366-ccompared withorf364. ORF366-C was predicted to contain one membrane-spanning domain using TMHMM online software. Real-time quantitative PCR analysis showed thatorf366-cwas upregulated in the CMS-C line in comparison to its maintainer line at the uninucleate stage. The protokaryotic protein expression oforf366-cinEscherichia colishowed that ORF366-C could be a cytotoxic protein. All the results indicated thatorf366-cmay be associated with maize CMS-C. [ABSTRACT FROM AUTHOR]

As introns are vulnerable to changes such as insertions and deletions when exposed to various evolutionary forces, they constitute a repository for developing genetic markers based on intron length polymorphisms (ILP). This study developed a set of genetic markers that use the potential intron length polymorphism in resistance gene analogs (RGAs) in Zea mays. By searching the genome of Zea mays B73 for the homologs of 73 R genes which have already been identified in plants, we found 861 RGAs, 632 of which have at least one intron that can serve as putative markers targeting the intron length polymorphism in RGAs (RGA-ILP). We developed 1972 candidate markers via electronic PCR (e-PCR) with primer pairs designed in each pair of exonic regions that flank an intron. Furthermore, the performance of RGA-ILP among four maize inbred lines (Huangzao4, B73, Mo17, and Dan340) was evaluated with 69 pairs of randomly selected primers. Of them, 46.4% showed bands that had discriminating length polymorphism, and between any two of the inbred lines the proportion of polymorphism ranged from 23.2 to 31.9%. To make it convenient to use these markers for those interested in molecular breeding of disease-resistant maize, we provide all related information in a web-based database named MaizeRGA, which is available at . [ABSTRACT FROM AUTHOR]

In order to adapt different languages and platforms, the paper discusses how to process and validate IDL symbol table and intermediate code by XML API. It puts emphasis on IDL API extension towards DOM API based on the idea of combining XML with IDL compilers. At last, the IDL compiler designing framework based on XML API is given, in which compiler front end can be managed and validated by some XML techniques and tools, IDL API can be validated on the basis of test, so IDL intermediate code is provided with maintainability, portability and generation. IDL compiler can be developed and extended by XML-based API, which realizes versatility and portability of modern compiler. [ABSTRACT FROM AUTHOR]

Flowering in higher plants is controlled by both the internal and environmental cues. In Arabidopsis, several major genetic loci have been defined as the key switches to control flowering. The Flowering Locus C (FLC) gene has been shown in the autonomous pathway to inhibit the vegetative-to-reproductive transition. FLC appears to be repressed by Flowering Locus D (FLD), which encodes a component of the histone deacetylase complex. Here we report the identification and characterization of a new mutant allele fld-5. Genetic analysis indicates that fld-5 (in the Wassilewskija background) is allelic to the previously characterized fld-3 and fld-4 (in the Colombia-0 background). Genetic and molecular analyses reveal that fld-5 carries a frame-shift mutation, resulting in a premature termination of the FLD open reading frame. The FLC expression is remarkably increased in fld-5, which presumably attributes to the extremely delayed flowering phenotype of the mutant. [ABSTRACT FROM AUTHOR]

Focuses on cytokinin signal transduction. Role of cytokinin in plant growth and development; Regulation of cell divisions and cell differentiation; Mediation of cytokinin signaling by a two-component system analogous to those found in bacteria and fungi; Transduction of an external signal via a phosphorelay from the plasma membrane-anchored receptors to downstream effectors and regulators.

Background: C-type cytoplasmic male sterility (CMS-C) is one of the three major types of cytoplasmic male sterility (CMS) in maize. Rf4 is a dominant restorer gene for CMS-C and has great value in hybrid maize breeding, but little information concerning its functional mechanism is known. Results: To reveal the functional mechanism of Rf4, we developed a pair of maize near-isogenic lines (NILs) for the Rf4 locus, which included a NIL_rf4 male-sterile line and a NIL_Rf4 male fertility-restored line. Genetic analysis and molecular marker detection indicated that the male fertility of NIL_Rf4 was controlled by Rf4. Whole-genome sequencing demonstrated genomic differences between the two NILs was clustered in the Rf4 mapping region. Unmapped reads of NILs were further assembled to uncover Rf4 candidates. RNA-Seq was then performed for the developing anthers of the NILs to identify critical genes and pathways associated with fertility restoration. A total of 7125 differentially expressed genes (DEGs) were identified. These DEGs were significantly enriched in 242 Gene Ontology (GO) categories, wherein 100 DEGs were involved in pollen tube development, pollen tube growth, pollen development, and gametophyte development. Homology analysis revealed 198 male fertility-related DEGs, and pathway enrichment analysis revealed that 58 DEGs were enriched in cell energy metabolism processes involved in glycolysis, the pentose phosphate pathway, and pyruvate metabolism. By querying the Plant Reactome Pathway database, we found that 14 of the DEGs were involved in the mitochondrial tricarboxylic acid (TCA) cycle and that most of them belonged to the isocitrate dehydrogenase (IDH) and oxoglutarate dehydrogenase (OGDH) enzyme complexes. Transcriptome sequencing and real-time quantitative PCR (qPCR) showed that all the above TCA cycle-related genes were up-regulated in NIL_Rf4. The results of our subsequent enzyme-linked immunosorbent assay (ELISA) experiments pointed out that the contents of both the IDH and OGDH enzymes accumulated more in the spikelets of NIL_Rf4 than in those of NIL_rf4. Conclusion: The present research provides valuable genomic resources for deep insight into the molecular mechanism underlying CMS-C male fertility restoration. Importantly, our results indicated that genes involved in energy metabolism, especially some mitochondrial TCA cycle-related genes, were associated with maize CMS-C male fertility restoration. [ABSTRACT FROM AUTHOR]

A correction to the article "Mining for Low-Nitrogen Tolerance Genes by Integrating Meta-Analysis and Large-Scale Gene Expression Data From Maize" by Bowen Luo et al. that was published in a 2015 issue is presented.