Endogenous small-noncoding RNAs and their roles in chilling response and stress acclimation in Cassava

BACKGROUND: Small noncoding RNA (sncRNA), including microRNAs (miRNAs) and endogenous small-interfering RNAs (endo-siRNAs) are key gene regulators in eukaryotes, playing critical roles in plant development and stress tolerance. Trans-acting siRNAs (ta-siRNAs), which are secondary siRNAs triggered by miRNAs, and siRNAs from natural antisense transcripts (nat-siRNAs) are two well-studied classes of endo-siRNAs. RESULTS: In order to understand sncRNAs’ roles in plant chilling response and stress acclimation, we performed a comprehensive study of miRNAs and endo-siRNAs in Cassava (Manihot esculenta), a major source of food for the world populations in tropical regions. Combining Next-Generation sequencing and computational and experimental analyses, we profiled and characterized sncRNA species and mRNA genes from the plants that experienced severe and moderate chilling stresses, that underwent further severe chilling stress after chilling acclimation at moderate stress, and that grew under the normal condition. We also included castor bean (Ricinus communis) in our study to understand conservation of sncRNAs. In addition to known miRNAs, we identified 32 (22 and 10) novel miRNAs as well as 47 (26 and 21) putative secondary siRNA-yielding and 8 (7 and 1) nat-siRNA-yielding candidate loci in Cassava and castor bean, respectively. Among the expressed sncRNAs, 114 miRNAs, 12 ta-siRNAs and 2 nat-siRNAs showed significant expression changes under chilling stresses. CONCLUSION: Systematic and computational analysis of microRNAome and experimental validation collectively showed that miRNAs, ta-siRNAs, and possibly nat-siRNAs play important roles in chilling response and chilling acclimation in Cassava by regulating stress-related pathways, e.g. Auxin signal transduction. The conservation of these sncRNA might shed lights on the role of sncRNA-mediated pathways affected by chilling stress and stress acclimation in Euphorbiaceous plants. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/1471-2164-15-634) contains supplementary material, which is available to authorized users

The Discrepant and Similar Responses of Genome-Wide Transcriptional Profiles between Drought and Cold Stresses in Cassava

Background: Cassava, an important tropical crop, has remarkable drought tolerance, but is very sensitive to cold. The growth, development, and root productivity of cassava are all adversely affected under cold and drought. Methods: To profile the transcriptional response to cold and drought stresses, cassava seedlings were respectively subjected to 0, 6, 24, and 48 h of cold stress and 0, 4, 6, and 10 days of drought stress. Their folded leaves, fully extended leaves, and roots were respectively investigated using RNA-seq. Results: Many genes specifically and commonly responsive to cold and drought were revealed: genes related to basic cellular metabolism, tetrapyrrole synthesis, and brassinosteroid metabolism exclusively responded to cold; genes related to abiotic stress and ethylene metabolism exclusively responded to drought; and genes related to cell wall, photosynthesis, and carbohydrate metabolism, DNA synthesis/chromatic structure, abscisic acid and salicylic acid metabolism, and calcium signaling commonly responded to both cold and drought. Discussion: Combined with cold- and/or drought-responsive transcription factors, the regulatory networks responding to cold and drought in cassava were constructed. All these findings will improve our understanding of the specific and common responses to cold and drought in cassava, and shed light on genetic improvement of cold and drought tolerance in cassava

Time to take corporate innovation initiatives: The consequence of safety accidents in China’s manufacturing industry

Purpose: A bad safety accident at a manufacturing company usually results in casualties and economic losses. The company affected by such an accident must deal with pressure from multiple stakeholder groups. Employees, in particular, play a key role in pushing the affected company to develop strategies to improve occupational safety and health. The purpose of this paper is to seek answers to two questions: does a safety accident affect employee behavior in terms of giving up prospects to develop a career at the affected company? If yes, could innovation initiatives adopted by the company help moderate the negative consequences from a safety accident? Design/methodology/approach: By investigating 120 safety accidents reported by publicly listed Chinese manufacturing companies between 2009 and 2016, the authors conduct an empirical study using regression-based statistical hypotheses testing to describe the companies’ responses and prospects for their employees. Findings: The results show that the magnitude of the accident and the accident being caused by an employee error positively affect the turnover of employees. Furthermore, technical innovation initiatives, such as spending on R&D, by the accident-affected companies increase the positive effect of the accident magnitude on employee turnover. On the contrary, management innovation initiatives, such as corporate social responsibility activities, weaken the impact of the accident magnitude and employee error on employee turnover. Originality/value: This study contributes to knowledge development by adding a crisis perspective in human resource management research. It helps to better understand the impact of safety accidents on employee behavior and the response taken by companies through innovation initiatives

Quantitative Analysis of the Instant and Persistent Inhibition Effects of Maternal Poliovirus Antibodies on the Immune Response in a Phase IV Trial of a Sabin Strain-Based Inactivated Poliovirus Vaccine

Background: An inactivated poliomyelitis vaccine made from Sabin strains (sIPVs) has widely been used in China since 2015. However, the quantitative data on the instant and persistent inhibition effects of maternal poliovirus antibodies on the immune response to sIPV priming and booster vaccination have not been available yet. Objective: In this study, we aim to explore and quantify the instant and persistent inhibition effect of maternal poliovirus antibodies on the immune response elicited by sIPV primary and booster vaccination. Methods: The immunogenicity data consisting of the days 0 and 30 after the prime and booster vaccination of the sIPV in a phase IV trial were pooled for a quantitative analysis of the inhibition effect of maternal poliovirus antibody. The geometric mean ratio (GMR) was calculated using linear regression models, representing that every 2-fold higher maternal poliovirus antibody titer may result in a (1-GMR) lower postimmunization antibody titer. Results: The GMRs for poliovirus types 1, 2, and 3 were 0.79 (0.77–0.82), 0.85 (0.81–0.89), and 0.87 (0.83–0.91) at 30 days after the priming series, 0.86 (0.83–0.89), 0.81 (0.76–0.85), and 0.86 (0.80–0.93) at one year after the priming series, and 0.96 (0.94–0.99), 0.89 (0.86–0.93), and 0.98 (0.93–1.03) at 30 days after the booster dose. The inhibition effect continued to exist until the booster dose 1 year later, and such a persistent inhibition effect was almost attenuated for poliovirus types 1 and 3, and partly reduced for type 2 at 30 days after the booster dose. Conclusion: A wider interval between the four sIPV doses might be a consideration for reducing the effect of maternal antibodies and subsequently eliciting and maintaining higher antibody levels to protect against poliovirus transmission and infection at the final stage of polio eradication in the global world. This study’s clinical trial registry number is NCT04224519

Development a novel drug delivery formulation targeting to esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is one of the most popular cancers in digestive tract. Chemotherapy is still the primary treatment for ESCC patients with or without surgery. But the efficacy of the current chemotherapy for ESCC is poor with side effects because of none or weak ESCC targeting and multidrug resistance (MDR). To develop a novel targeting peptide for ESCC targeting diagnosis and therapy, a novel peptide, ESCP9 was screened from a 12-mer phage displayed peptide library. The satisfied sensitivity and specificity of ESCP9 binding to ESCC were characterized with cellular and tissue assays under fluorescence microscope, and by flow cytometry. By the assay of molecular docking, protein kinase C (PKC) was predicted as the target ESCP9 binding to. To develop a novel ESCC targeted and MDR inhibited doxorubicin (DOX) liposomal delivery formulation for ESCC targeting chemotherapy, the DOX delivery formulation (ESCP9-Lipo-DOX-miR101) was synthesized and characterized by using ESCP9 as ESCC directing fragment and miRNA101 as MDR suppressor. Finally, the therapeutic efficacy of the drug formulation for ESCC therapy was primarily evaluated by the therapeutic assay for the wild type and DOX resistant ESCC cells in vitro. The results demonstrated that the drug formulation enhanced cytotoxicity to Eca-109 cells and DOX-resistant Eca-109 cells (Eca-109/ADR) significantly. It is concluded that ESCP9 is a targeting peptide with high specificity and sensitivity, and the ESCP9 conjugated DOX liposomal formulation, ESCP9-Lipo-DOX-miR101, is of the potential to be further studied as an efficient drug formulation for ESCC and DOX resistant ESCC chemotherapy in future

PP2A activates brassinosteroid-responsive gene expression and plant growth by dephosphorylating BZR1.

When brassinosteroid levels are low, the GSK3-like kinase BIN2 phosphorylates and inactivates the BZR1 transcription factor to inhibit growth in plants. Brassinosteroid promotes growth by inducing dephosphorylation of BZR1, but the phosphatase that dephosphorylates BZR1 has remained unknown. Here, using tandem affinity purification, we identified protein phosphatase 2A (PP2A) as a BZR1-interacting protein. Genetic analyses demonstrated a positive role for PP2A in brassinosteroid signalling and BZR1 dephosphorylation. Members of the B' regulatory subunits of PP2A directly interact with BZR1's putative PEST domain containing the site of the bzr1-1D mutation. Interaction with and dephosphorylation by PP2A are enhanced by the bzr1-1D mutation, reduced by two intragenic bzr1-1D suppressor mutations, and abolished by deletion of the PEST domain. This study reveals a crucial function for PP2A in dephosphorylating and activating BZR1 and completes the set of core components of the brassinosteroid-signalling cascade from cell surface receptor kinase to gene regulation in the nucleus