The Plant Salicylic Acid Signalling Pathway Regulates the Infection of a Biotrophic Pathogen in Grasses Associated with an Epichloë Endophyte.

The study of the contribution of the plant defence hormones, salicylic acid (SA) and jasmonic acid (JA), in the resistance against pathogens of plants associated with Epichloë fungal endophytes has been scanty. We hypothesised that Epichloë spp., capable of inducing host plant SA-dependent defences, would increase the levels of plant resistance against biotrophic pathogens. Plants of Achnatherum inebrians, with and without the fungal endophyte Epichloë gansuensis, were inoculated with the biotrophic fungal pathogen Blumeria graminis. We measured the status of plant defences (associated with SA and JA signalling pathways) and the levels of resistance to the pathogen. Plants associated with the endophyte showed less disease symptoms caused by the biotrophic pathogen than plants without the endophyte. In agreement with our hypothesis, the Epichloë endophyte increased the plant production of SA and enhanced the expression levels of plant genes of synthesis and response to the SA hormone. The elevated expression of SA-related genes coding for putative plant enzymes with anti-fungal activities promoted by the endophyte may explain the enhanced resistance to the pathogen. The present study highlights that interaction between the plant immune system and Epichloë fungal endophytes can contribute significantly to the resistance of endophyte-symbiotic plants against pathogens.

An epigenome-wide DNA methylation study of workers with an occupational exposure to lead.

Using the Illumina Infinium Methylation EPIC BeadChip (850 K), we report genome-wide differences in DNA methylation between occupational workers with high blood Pb levels (BLL) and low BLL. We observed 356 significant CpG sites. In particular, GSTM1 methylation was negatively associated with high BLL. Gene ontology and KEGG pathway enrichment analysis were performed to determine the complex biological systems of Pb exposure. Enriched gene sets were involved in the oxidation-reduction process, glutathione derivative biosynthetic process and nervous system development. To our knowledge, this is the first study to employ an 850 K array to examine whether workers with occupational exposure to high levels of Pb can have an epigenetic effect on the DNA methylation pattern.

Dahurelmusin A, a Hybrid Peptide-Polyketide from Elymus dahuricus Infected by the Epichloë bromicola Endophyte.

One novel hybrid peptide-polyketide, dahurelmusin A (1), was isolated from Elymus dahuricus infected by the Epichloë bromicola endophyte. Comprehensive spectroscopic analysis revealed that 1 is the first example of hybrid peptide-polyketide possessing an unprecedented 5-hydroxy-2,2,4,6-tetramethyl-3-oxooctanoic acid moiety. The single-crystal X-ray diffraction analyses allowed the absolute configuration assignment of this compound. Compound 1 also exhibited significant insecticidal activities against Rhopalosiphum padi and Brevicoryne brassicae with LC50 values of 0.092 and 0.251 mM, respectively.

Antifungal, Phytotoxic, and Cytotoxic Activities of Metabolites from Epichloë bromicola, a Fungus Obtained from Elymus tangutorum Grass.

The development of high-quality herbage is an important aspect of animal husbandry. Inoculating beneficial fungi onto inferior grass is a feasible strategy for producing new varieties of high-quality herbage. Epichloë bromicola is a candidate fungus that is isolated from Elymus tangutorum. A total of 17 metabolites, 1-17, were obtained from E. bromicola, and their biological activities were assayed. Metabolite 1 exhibited antifungal activities against Alternaria alternata, Fusarium avenaceum, Bipolaris sorokiniana, and Curvularia lunata. EC50 values ranged from 0.7 to 5.3 µM, which were better than the positive control, chlorothalonil. Metabolite 8 displayed obvious phytotoxic effects toward Lolium perenne and Poa crymophila seedlings, and it was as active as glyphosate. None of these isolated metabolites displayed cytotoxicity against Madin-Darby bovine kidney cells. The IC50 values were greater than 100 µM, and the metabolites increased the growth of the cells at a concentration of 12.5 µM. The bioassay indicated that E. bromicola may be a beneficial fungus for producing new varieties of herbage with various resistances. Additionally, metabolite 7, 3-(2'-(4″-hydroxyphenyl)acetoxy)-2S-methylpropanoic acid, is a new natural product, and its stereochemistry was determined by means of optical rotation computation and chemical reactions.

[The occupational and procreation health of immigrant female workers in electron factory].

OBJECTIVE: To explore the occupational and reproductive health problems of migrant female workers in electron factory. METHODS: A total number of 2000 female migrant workers were randomly sampled from three electronic factories for the study. All were investigated by questionnaire and data were input to EpiData 3.0 data base, SPSS17.0 statistical software and analyzed by Chi-square test. RESULTS: 1971 complete questionnaires were received, the recovery rate reached over 98.6%. The average age of interviewees is (21.1 ± 3.9) years. Junior employee between 16 and 18 years accounted for 19.04%. The average working age was (1.1 ± 2.2) years and about 90% were single including 0.11% of them were divorced. The main occupational hazards were: sodium hydroxide, sodium carbonate, formaldehyde, hydrochloric acid, stannic anhydride, benzene analogues, n-hexane methanol, glycol isopropanol, sulphuric acid, nitric oxide, noise, ultraviolet radiation, etc. Workplace monitoring indicated that benzene and noise levels and ultraviolet radiation were over the national OEL at fewer worksites. More than 50% female workers worked over 8 hours per day and 83% of them worked 22 days per month. The ergonomic problems: 63.86% of them worked with tedious repetitiveness and monotonous job task. About 42% of them need to be continuously with standing posture. As a consequence, there were 30% workers complain about LBP, 21% had experienced work injury; 15% ∼ 18% had some non-specific discomfort, such as insomnia, dysacusis, dizzy and headache. The incidence rate of reproductive system such as abnormal menstrual cycle (5.71%), dysmenorrhea (25.11%), congestion (8.91%), etc. The first four reproductive system disease were pelvic inflammation, adnexitis, cervical erosion, and vaginitis. There are significant differences between continuous and temporary standing work, and repeated and unrepeated job action in terms of dysmenorrheal and congestion related-discomfort(P < 0.05). CONCLUSION: There are many occupational hazards in electronic industry. And there is somewhat a serious occupational and reproductive health problems among female migrant workers, that seem to be a matter of great concern.