Genetic transformation and expression of transgenic lines of Populus x euramericana with insect-resistance and salt-tolerance genes.

We characterized new transgenic varieties of poplar with multiple insect-resistant and salt stress tolerant genes. Two insect-resistant Bacillus thuringiensis (Bt) genes, Cry1Ac and Cry3A, and a salt-tolerant gene, Betaine aldehyde dehydrogenase (BADH) were inserted into a vector, p209-Cry1Ac-Cry3A-BADH. The clone of Populus x euramericana was transformed by the vector using the Agrobacterium-mediated method. Three transgenic lines were assessed using genetic detection and resistance expression analysis. PCR revealed that exogenous genes Cry1Ac, Cry3A, BADH and selective marker gene NPTII were present in three transgenic lines. Quantitative real-time PCR (qPCR) showed significant differences in the transcriptional abundance of three exogenous genes in different lines. Results of assays for Bt toxic proteins showed that the Cry1Ac and Cry3A toxic protein content of each line was 12.83-26.32 and 2108.91-2724.79 ng/g, respectively. The Cry1Ac toxic protein content of different lines was significantly different; the Cry3A toxic protein content was about 100 times higher than that of the Cry1Ac toxic protein. The insect-resistance test revealed the mortality rate of transgenic lines to Hyphantria cunea L1 larvae varied by 42.2-66.7%, which was significantly higher than non-transgenic lines. The mortality rate of L1 and L2 Plagiodera versicolora larvae was 100%. The insecticidal effect of transgenic lines to P. versicolora larvae was higher than that to H. cunea larvae. NaCl stress tolerance of three transgenic lines under 3-6% NaCl concentration was significantly higher than that of non-transgenic lines.

Meta-analysis confirms that a common G/C variant in the pre-miR-146a gene contributes to cancer susceptibility and that ethnicity, gender and smoking status are risk factors.

Evidence has shown that miR-146a is involved in carcinogenesis, and a common G/C variant (rs2910164) in the pre-miR-146a gene has been associated with various types of cancer. We summarized the data from 22 published case-control studies on the association between rs2910164 and cancer risk and performed subgroup analyses by ethnicity, gender and smoking status. We found a significant association between the pre-miR-146a polymorphism and cancer risk in Caucasian populations (odds ratio (OR) = 0.93, 95% confidence interval (CI) = 0.88-0.99 for G- vs C-allele), while the significance was borderline in Asian populations (OR = 1.11, 95%CI = 1.00-1.23 for G- vs C-allele). A significantly increased risk of cancer was found in males with GG/GC genotypes (OR = 1.23, 95%CI = 1.10- 1.37), and the significance was more pronounced in smokers (OR = 1.82, 95%CI = 1.32-2.51) than in non-smokers (OR = 1.24, 95%CI = 1.01-1.53). We conclude that there is evidence that the pre-miR-146a polymorphism contributes to cancer susceptibilities and that gender and smoking status affect the probability of cancer in individuals with this polymorphism.