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Saccharomyces cerevisiae always faces various environmental stresses during industrial-scale fermentation, including oxidation, high temperature, acid, ethanol, and hyperosmosis. Therefore, screening and breeding of strains with high tolerance to these stresses is of great significance for industrial applications. It is well known that DNA recombination enzyme, nucleic acid repair enzyme, and other proteins involved in nucleic acid repair pathway play important roles in tolerance to abiotic stresses. Based on that, the effects of endogenous nucleic acid excision and repair genes (RAD16, RAD7, RAD23 and RAD4) and exogenous genes (UVRA) on the tolerance of S. cerevisiae to different stresses were investigated by gene editing. The results showed that overexpression of RAD16, RAD7, RAD23 and RAD4 could improve the tolerance against osmotic stress in S. cerevisiae. Furthermore, overexpression of UVRA gene from bacterium Acetobacter pasteurii could also improve the tolerance against osmotic stress, suggesting that the function of UVRA was conserved between eukaryotic and procaryotic cells. This results were beneficial to improvement of the tolerance of S. cerevisiae strains, especially under high osmotic stress, and also provide a novel strategy to reveal the mechanism of tolerance in yeast. [ABSTRACT FROM AUTHOR]

Background and Objective It has been proven that ERCC1 (excision repair cross-complementation group 1) plays an important role in tumor sensitivity to platinum-based chemotherapy. This study was to examine the relationship between ERCC1 expression in NSCLC and efficacy of neoadjuvant chemotherapy. Methods Expression levels of ERCC1 in 73 resected patients with NSCLC were detected with the method of immunohistochemistry. Expression differents of ERCC1 and its relationship with neoadjuvant chemotherapy were analysed with chi-square test, Log-rank test and Cox regression model risk. Results The positive rate of ERCC1 in NSCLC was 34.25%. Expression rate for ERCC1 in NSCLC treated with neoadjuvant chemotherapy was significantly higher than in those without neoadjuvant group (48.48% vs 20.45%, P=0.025). Compared with the patients with ERCC1-negative tumors, the response rate in the patients with ERCC1-positive tumors was 31.3% vs 58.8% (X^2=2.528, P=0.112), median survival time was 36 months vs 54 months (P=0.118), The 3-year overall survival rate were 43.8% vs 47.1% (X^2=0.029, P=0.866) and The 5-year overall survival rate were 18.8% vs 23.5% (X^2=0.414, P=0.520). COX multivariate regression analysis showed that disease stages, ERCC1 expression and neoadjuvant chemotherapy were independent prognostic facts in the patients. Conclusions The expression level of ERCC1 is related to the prognosis in patients with NSCLC with neoadjuvant CT. Neoadjuvant CT can induce ERCC1 gene.