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Sustainable development has received worldwide attention. Recent studies on corporate environmental behavior have called for research from the specific stakeholder's perspective (i.e., consumer) on the topic of going green. Based on reputation theory, this paper employed a secondary data analysis and three experiments to highlight the influence of environmental irresponsibility on corporate reputation perceived by consumers. Coherent results showed that environmental irresponsibility negatively affected corporate reputation and perceived corporate ethics served as a mediator. Furthermore, corporate social responsibility (CSR) activities could alleviate the harmful consequences of irresponsible behavior by moderating the mediating role of perceived corporate ethics in determining the influence of environmental irresponsibility.

SummaryTwo-component systems are predominant signal transduction pathways in prokaryotes, and also exist in many archaea as well as some eukaryotes. A typical TCS consists of a histidine kinase and a cognate response regulator. In this study, a novel gene encoding a response regulator (we designate it drRRA) is identified to be essential for the extreme radioresistance of Deinococcus radiodurans. DrRRA null mutant (we designate it MR) is sensitive to gamma-radiation compared with the wild-type strain. Transcriptional assays show that numerous genes are changed in their transcriptional levels in MR at exponential growth phase under normal or gammaradiation condition. Most of them are related to stress response and DNA repair. Antioxidant activity assays exhibit that both superoxide dismutases and catalases are decreased in the mutant, whereas Western blotting assays show that RecA and PprA are also reduced in MR, verifying the microarray and quantitative real-time PCR data. Furthermore, pulsed-field gel electrophoresis assay demonstrates that deletion of drRRA results in the delay of genome restitution. These data support the hypothesis that DrRRA contributes to the extreme radioresistance of D. radiodurans through its regulatory role in multiple pathways such as antioxidation and DNA repair pathways.

A series of long-chain branched poly(L-lactide)s (LCB-PLAs) with controlled branch length were prepared by a simple and efficient method through a combination of ring-opening polymerization (ROP) of L-lactide and a coupling reaction between the terminal OH groups of the PLA prepolymers and the NCO groups of HDI. The influences of reaction conditions on the synthesis of the LCB-PLAs were investigated, and the structures of the resultant LCB-PLAs were characterized by 1 H NMR spectroscopy and SEC-MALLS. By adjusting the degree of polymerization and the composition of the prepolymers, LCB-PLAs with different branch densities and molecular weights between branch points were obtained. The effect of macromolecular chain branching on the rheology and crystallization of PLA was also investigated. The LCB structure contributed to the enhancement of the zero-shear viscosity, complex viscosity, storage modulus, melt strength, and strain hardening under elongational flow. Thermal behavior indicated that the branch structure resulted in a short nucleation induction period and more rapid crystallization, which can be a guarantee of high-strength foams.

The resection of DNA strand with a 5´ end at double-strand breaks is an essential step in recombinational DNA repair. RecJ, a member of DHH family proteins, is the only 5´ nuclease involved in the RecF recombination pathway. Here, we report the crystal structures of Deinococcus radiodurans RecJ in complex with deoxythymidine monophosphate (dTMP), ssDNA, the C-terminal region of single-stranded DNA-binding protein (SSB-Ct) and a mechanistic insight into the RecF pathway. A terminal 5´-phosphate-binding pocket above the active site determines the 5´-3´ polarity of the deoxy-exonuclease of RecJ; a helical gateway at the entrance to the active site admits ssDNA only; and the continuous stacking interactions between protein and nine nucleotides ensure the processive end resection. The active site of RecJ in the N-terminal domain contains two divalent cations that coordinate the nucleophilic water. The ssDNA makes a 180° turn at the scissile phosphate. The C-terminal domain of RecJ binds the SSB-Ct, which explains how RecJ and SSB work together to efficiently process broken DNA ends for homologous recombination.DOI: http://dx.doi.org/10.7554/eLife.14294.001

Primary and acquired drug resistance is one of the main obstacles encountered in high-grade serous ovarian cancer (HGSC) chemotherapy. Cisplatin induces DNA damage through cross-linking and long integrated non-coding RNAs (lincRNAs) play an important role in chemical induced DNA-damage response, which suggests that lincRNAs may be also associated with cisplatin resistance. However, the mechanism of long integrated non-coding RNAs (lincRNAs) acting on cisplatin resistance is not well understood. Here, we showed that expression of lin-RECK-3, H19, LUCAT1, LINC00961, and linc-CARS2-2 was enhanced in cisplatin-resistant A2780-DR cells, while transcriptome sequencing showed decreased Linc-TNFRSF19-1 and LINC00515 expression. Additionally, we verified that different H19 expression levels in HGSC tissues showed strong correlation with cancer recurrence. H19 knockdown in A2780-DR cells resulted in recovery of cisplatin sensitivity in vitro and in vivo. Quantitative proteomics analysis indicated that six NRF2-targeted proteins, including NQO1, GSR, G6PD, GCLC, GCLM and GSTP1 involved in the glutathione metabolism pathway, were reduced in H19-knockdown cells. Furthermore, H19-knockdown cells were markedly more sensitive to hydrogen-peroxide treatment and exhibited lower glutathione levels. Our results reveal a previously unknown link between H19 and glutathione metabolism in the regulation of cancer-drug resistance.

The extremophilic bacterium Deinococcus radiodurans exhibits an extraordinary resistance to ionizing radiation. Previous studies established that a protein named PprI, which exists only in the Deinococcus-Thermus family, acts as a general switch to orchestrate the expression of a number of DNA damage response (DDR) proteins involved in cellular radio-resistance. Here we show that the regulatory mechanism of PprI depends on its Mn(2+)-dependent protease activity toward DdrO, a transcription factor that suppresses DDR genes’ expression. Recognition sequence-specificity around the PprI cleavage site is essential for DNA damage repair in vivo. PprI and DdrO mediate a novel DNA damage response pathway differing from the classic LexA-mediated SOS response system found in radiation-sensitive bacterium Escherichia coli. This PprI-mediated pathway in D. radiodurans is indispensable for its extreme radio-resistance and therefore its elucidation significantly advances our understanding of the DNA damage repair mechanism in this amazing organism.

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