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Abstract: In an attempt to improve the enzymatic efficiency in ball mill, a novel immobilized cellulase on polyvinyl alcohol/Fe2O3 magnetic nanoparticle with high activity was synthesized and characterized by transmission electron microscopy, Zetasizer, Fourier transform infrared (FTIR) spectroscopy and vibrating sample magnetometry. It was found that the immobilized cellulase was a kind of spherical complex with approximate 270nm, 4.87Am2 kg−1, and mainly constructed by the accumulation of 10nm Fe2O3 nanoparticles with the diffused polymer. When the immobilized cellulase was applied to degrade microcrystalline cellulose by combining with wet ball milling, the yielded glucose was 1.89mgmL−1, at least three times than the sum of individual yield. The immobilized cellulose maintained 40% activity even after four cycles of reuse. From these results, it can be concluded that the immobilization of cellulase with wet ball milling is a novel method to significantly improve the efficiency of cellulose conversion. [ABSTRACT FROM AUTHOR]

Endophytes can colonize a host plant without inducing obvious disease symptoms. Elicitors from endophytes may play important roles in balancing endophyte colonization. We identified a novel endophytic elicitor from Colletotrichum tofieldiae, CtRALF, that has structural and functional characteristics similar to those of rapid alkalinization factor (RALF) peptides in Arabidopsis thaliana. We found that CtRALF can directly interact with the host plant receptor‐like kinase FERONIA (FER). The colonization of FER mutant plants by hyphae of C. tofieldiae was obviously reduced compared with that on wild‐type plants. Furthermore, the interaction of CtRALF with FER regulated symbiotic signals by triggering calcium waves, inhibiting reactive oxygen species bursts, increasing mitogen‐activated protein kinase phosphorylation and reducing the stabilization of MYC2. Collectively, these results suggested that the RALF homologue of endophytes may improve their symbiosis by interacting with host plant‐encoded FER. [ABSTRACT FROM AUTHOR]

The molecular links between extracellular signals and the regulation of localized protein synthesis in plant cells are poorly understood. Here, we show that in Arabidopsis thaliana , the extracellular peptide RALF1 and its receptor, the FERONIA receptor kinase, promote root hair (RH) tip growth by modulating protein synthesis. We found that RALF1 promotes FERONIA-mediated phosphorylation of eIF4E1, a eukaryotic translation initiation factor that plays a crucial role in the control of mRNA translation rate. Phosphorylated eIF4E1 increases mRNA affinity and modulates mRNA translation and, thus, protein synthesis. The mRNAs targeted by the RALF1–FERONIA–eIF4E1 module include ROP2 and RSL4, which are important regulators of RH cell polarity and growth. RALF1 and FERONIA are expressed in a polar manner in RHs, which facilitate eIF4E1 polar localization and thus may control local ROP2 translation. Moreover, we demonstrated that high-level accumulation of RSL4 exerts negative-feedback regulation of RALF1 expression by directly binding the RALF1 gene promoter, determining the final RH size. Our study reveals that the link between RALF1–FERONIA signaling and protein synthesis constitutes a novel component regulating cell expansion in these polar growing cells. This study found that RALF1 promotes the FERONIA-mediated phosphorylation of eIF4E1, which recognizes the mRNA cap, increases mRNA affinity, and modulates mRNA translation. The mRNAs targeted by the RALF1–FERONIA–eIF4E1 module include the root hair (RH) genes ROP2 and RSL4. Moreover, high levels of RSL4 exert negative-feedback regulation on RALF1 expression by directly binding the RALF1 gene promoter, determining the final RH cell size. [ABSTRACT FROM AUTHOR]

The molecular mechanism by which plants defend against plant root-knot nematodes (RKNs) is largely unknown. The plant receptor kinase FERONIA and its peptide ligands, rapid alkalinization factors (RALFs), regulate plant immune responses and cell expansion, which are two important factors for successful RKN parasitism. In this study, we found that mutation of FERONIA in Arabidopsis thaliana resulted in plants showing low susceptibility to the RKN Meloidogyne incognita. To identify the underlying mechanisms associated with this phenomenon, we identified 18 novel RALF-likes from multiple species of RKNs and showed that two RALF-likes (i.e., MiRALF1 and MiRALF3) from M. incognita were expressed in the esophageal gland with high expression during the parasitic stages of nematode development. These nematode RALF-likes also possess the typical activities of plant RALFs and can directly bind to the extracellular domain of FERONIA to modulate specific steps of nematode parasitism-related immune responses and cell expansion. Genetically, both MiRALF1/3 and FERONIA are required for RKN parasitism in Arabidopsis and rice. Collectively, our study suggests that nematode-encoded RALFs facilitate parasitism via plant-encoded FERONIA and provides a novel paradigm for studying host–pathogen interactions. Eighteen novel RALF-likes were identified from multiple species of root-knot nematodes (RKNs). Both nematode RALF-likes and the plant receptor kinase FERONIA were found to be required for RKN parasitism in Arabidopsis and rice. Nematode RALF-likes are expressed in the esophageal gland and serve as ligands of FERONIA to modulate the immune response and facilitate parasitism, providing a novel paradigm for studying host–pathogen interactions. [ABSTRACT FROM AUTHOR]

The ratio between carbon (C) and nitrogen (N) utilization must be precisely coordinated to enable plant growth. Although numerous physiological studies have examined carbon/nitrogen (C/N) ratios, the mechanisms of sensing the C/N balance and C/N signaling remain elusive. Here, we report that a mutation of FERONIA (FER), a receptor kinase that plays versatile roles in plant cell growth and stress responses, caused hypersensitivity to a high C/N ratio in Arabidopsis. In contrast, FER -overexpressing plants displayed more resistant phenotypes. FER can interact with and phosphorylate ATL6, an E3 ubiquitin ligase that has been shown to regulate plant C/N responses. FER-mediated ATL6 phosphorylation enhanced the interaction between ATL6 and its previously identified target 14-3-3 proteins, thus decreasing 14-3-3 protein levels, leading to an increased insensitivity to high C/N ratios. Further analyses showed that the rapid alkalinization factor peptide (RALF1), which is a ligand of FER, also influenced the stability of 14-3-3 proteins via a FER–ATL6-mediated pathway. These findings reveal a novel regulatory mechanism that links the RALF1/FER–ATL6 pathway to whole-plant C/N responses and growth. [ABSTRACT FROM AUTHOR]

Abstract A series of novel aryloxyphenoxypropionate (APP) herbicides containing benzofuran moiety were designed, synthesized and tested for herbicidal activity. The bioassay results indicated that most of target compounds possessed moderate to good herbicidal activity against monocotyledonous weeds. Compounds 5a - 5d and 6a - 6d showed 100% control efficiency against crabgrass (Digitaria sanguinalis) and barnyard grass (Echinochloa crus-galli) in both pre-emergence and post-emergence treatments at the dosage of 1500 g a.i. ha−1. Compound 6c was the most promising, with herbicidal activity better than clodinafop-propargyl. Molecular docking for compound 6c and its hydrolysis acid 1c were performed. ACCase activities of some compounds were also tested. Theoretical calculations for corresponding hydrolysis products 1a - 1e were carried out. Based on the results of molecular docking, enzyme activity test and theoretical calculation, the potential mechanism for herbicidal activity of these compounds was evaluated. Graphical abstract Unlabelled Image Highlights • A series of novel aryloxyphenoxypropionate herbicides were designed,synthesized and tested for herbicidal activity. • The herbicidal activity of compound 6c was better than that of clodinafop-propargyl. • The potential mechanism of action has been proposed by molecular docking, enzyme activity test and theoretical calculation. • The results of this study will contribute to designing higher herbicidal activity compounds. [ABSTRACT FROM AUTHOR]

FERONIA (FER), a plasma membrane receptor-like kinase, is a central regulator of cell growth that integrates environmental and endogenous signals. A peptide ligand rapid alkalinization factor 1 (RALF1) binds to FER and triggers a series of downstream events, including inhibition of Arabidopsis H+-ATPase 2 activity at the cell surface and regulation of gene expression in the nucleus. We report here that, upon RALF1 binding, FER first promotes ErbB3-binding protein 1 (EBP1) mRNA translation and then interacts with and phosphorylates the EBP1 protein, leading to EBP1 accumulation in the nucleus. There, EBP1 associates with the promoters of previously identified RALF1-regulated genes, such as CML38, and regulates gene transcription in response to RALF1 signaling. EBP1 appears to inhibit the RALF1 peptide response, thus forming a transcription–translation feedback loop (TTFL) similar to that found in circadian rhythm control. The plant RALF1-FER-EBP1 axis is reminiscent of animal epidermal growth factor receptor (EGFR) signaling, in which EGF peptide induces EGFR to interact with and phosphorylate EBP1, promoting EBP1 nuclear accumulation to control cell growth. Thus, we suggest that in response to peptide signals, plant FER and animal EGFR use the conserved key regulator EBP1 to control cell growth in the nucleus. Author summary: Receptor-like kinase FERONIA (FER) is an important regulator of plant growth and stress response and is activated by binding its peptide ligand, rapid alkalinization factor 1 (RALF1). However, how FER, a plasma membrane–localized receptor protein, regulates gene expression in the nucleus remains unclear. Here, we show that RALF1-FER signaling increases the abundance of ErbB3-binding protein 1 (EBP1) protein, which then accumulates in the nucleus and controls gene expression. The receptor kinase FER also directly interacts with and phosphorylates EBP1, a required step for EBP1 accumulation in the nucleus. Ultimately, EBP1 protein binds to the promoters of some RALF1-FER-regulated genes and inhibits their expression, leading to a negative regulation of RALF1-FER response. This study thus reveals a link between a plasma membrane receptor and the control of gene expression in the nucleus and establishes a similar mode of action for EBP1 in both animals and plants. [ABSTRACT FROM AUTHOR]

FERONIA (FER), a plasma membrane receptor-like kinase, is a central regulator of cell growth that integrates environmental and endogenous signals. A peptide ligand rapid alkalinization factor 1 (RALF1) binds to FER and triggers a series of downstream events, including inhibition of Arabidopsis H+-ATPase 2 activity at the cell surface and regulation of gene expression in the nucleus. We report here that, upon RALF1 binding, FER first promotes ErbB3-binding protein 1 (EBP1) mRNA translation and then interacts with and phosphorylates the EBP1 protein, leading to EBP1 accumulation in the nucleus. There, EBP1 associates with the promoters of previously identified RALF1-regulated genes, such as CML38, and regulates gene transcription in response to RALF1 signaling. EBP1 appears to inhibit the RALF1 peptide response, thus forming a transcription–translation feedback loop (TTFL) similar to that found in circadian rhythm control. The plant RALF1-FER-EBP1 axis is reminiscent of animal epidermal growth factor receptor (EGFR) signaling, in which EGF peptide induces EGFR to interact with and phosphorylate EBP1, promoting EBP1 nuclear accumulation to control cell growth. Thus, we suggest that in response to peptide signals, plant FER and animal EGFR use the conserved key regulator EBP1 to control cell growth in the nucleus. [ABSTRACT FROM AUTHOR]

BACKGROUND Biocontrol is a promising strategy in the control of rice blast disease. In the present study, we isolated and characterized a novel antagonist to the pathogen Magnaporthe oryzae from rice endophytic actinomycetes. RESULTS Out of 482 endophytic actinomycetes isolated from rice blast infected and healthy rice, Streptomyces endus OsiSh-2 exhibited remarkable in vitro antagonistic activity. Scanning electron microscopy observations of M. oryzae treated by OsiSh-2 revealed significant morphological alterations in hyphae. In 2-year field tests, the spraying of OsiSh-2 spore solution (107 spores mL−1) is capable of reducing rice blast disease severity by 59.64%. In addition, a fermentation broth of OsiSh-2 and its cell-free filtrates could inhibit the growth of M. oryzae, suggesting the presence of active enzymes and secondary metabolites. OsiSh-2 tested positive for polyketide synthase-I and nonribosomal peptide synthetase genes and can produce cellulase, protease, gelatinase, siderophore, indole-3-acetic acid and 1-amino-cyclopropane-1-carboxylate deaminase. A preliminary separation indicated that the methanol extract of OsiSh-2 could suppress the growth of pathogens. The major active component was identified as nigericin. CONCLUSION Endophytic S. endus OsiSh-2 has potential as a biocontrol agent against rice blast in agriculture. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The Arabidopsis gene FERONIA (FER) regulates cell elongation and fertility. Although the function of FER in promoting plant growth and regulating fructification in dicotyledon Arabidopsis has been investigated, how homologous FERONIA-like receptors (FLRs) function in the monocotyledon rice crop is little known. In this study, we generated flr1 and flr2 T-DNA insertion null mutants and investigated potential role of FLRs in rice yield. We observed that both FLR1 and FLR2 were involved in tillering of rice, but at different levels. Interestingly, FLR1 and FLR2 showed different functions related to fertility, and FLR1 might be specifically involved in rice male gametophyte development. With these similar but different functions, we suggest that FLR1 and FLR2 might function in complementary ways to regulate the yield of rice. The similar and different functions of FLR1 and FLR2 also suggest that there might be differentiation from FER to the duplication of FLRs, with FLR1 and FLR2 taking on partial functions from FER. [ABSTRACT FROM AUTHOR]

Modified magnetic starch nanoparticles (FA-StNP@Fe2O3) were synthesized by conjugating folic acid (FA-PEG-NH2) onto the surface of magnetic starch nanoparticles (StNP@Fe2O3) prepared by reverse microemulsion method. The synthesized FA-StNP@Fe2O3 was investigated by transmission electron microscopy and zeta potential analysis. The average size of its well dispersed particles was 250 nm. The iron concentration of 2 mg/g was detected by phenanthroline method. Placing FA-StNP@Fe2O3 nanoparticles in the alternating magnetic field for 30 min resulted in an increase in the suspension temperature from ambient temperature (37°) to a value between 42° and 43°. Co-cultured nanoparticles and Hela cell line or normal HUEC-12 cell line, and the biological effects at the cellular level were investigated in the alternating magnetic field using MTT assay, Hochest-PI double staining and flow cytometry analysis. Experimental results showed that FA-StNP@Fe2O3 within acertain concentration range has no obvious effect on cell proliferation. When treated in the magnetic field, apoptosis rate on Hela induced by FA-StNP@Fe2O3 was 13.4%. Prussian blue staining analysis confirmed that the nanoparticles modified with folic acid had improved ability in tumor cell-targeting, and therefore, potential applications in biomedical and magnetocaloric areas. It is expected be applied in tumor targeting therapy in the near future. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we reported that a novel biosensor was developed to detect early apoptotic cells by the specific interaction between Annexin V and phosphatidylserine based on electrochemical impedance. Annexin V was immobilized on a self-assembled layer of gold nanoparticles, which allowed stable and high loading of Annexin V on the electrode surface, offering the possibility of sensitivity enhancement. Early apoptotic cells showed an increased exposition of phosphatidylserine on the cell membrane caused by physiological and pathological response reaction, leading to a strong interaction between the apoptotic cells and the electrode surface, which could be probed by electrochemical impedance spectroscopy. As examined using a model system of cells integrated by phosphatidylserine-modified liposome and a real one of early apoptotic cell induced by 5-fluorouracil, this biosensor demonstrated the great potential for rapid detection of cell apoptosis and drug screening. The results agreed well with those obtained using fluorescence microscopy and flow cytometry. [Copyright &y& Elsevier]

The cover image, by Ting Xu et al., is based on the Research Article Isolation and evaluation of endophytic Streptomyces endus OsiSh-2 with potential application for biocontrol of rice blast disease, DOI: . [ABSTRACT FROM AUTHOR]