Exploring the Effects of E-Cigarettes using Drosophila Melanogaster

Although the number of vaping-related deaths in the US is rising, the specific cause remains unidentified. Therefore, determining what long-term effects vegetable glycerin (VG) and propylene glycol (PG), the main non-nicotine components in e-cigarettes, may have is crucial. Discovering that these components are harmful when tested on fruit flies (Drosophila melanogaster), a model organism, may suggest similar effects in humans. In this study, the number of offspring, changes in behavior, and phenotypic mutations in fruit flies were observed for the parent, F1, and F2 generations after the parent generation was exposed to one of four treatments of aerosolized solution. These included a 50% PG/50% VG, a 30% PG/70% VG, a 70% PG/30% VG, or no solution (control) using a nebulizer for 18 seconds each day, for two days. It was found that each experimental group had fewer offspring than the control. A two-sample T-test (α = 0.05) was used to find that the size of the flies in the F1 generation was statistically significantly smaller in ⅔ of the experimental groups when compared to the control. Furthermore, it was observed using a two-proportion Z-test (α = 0.05) that ⅔ of experimental groups in the parent generation, and all F1 experimental groups were statistically significantly more likely to develop at least one phenotypic mutation than the control. Additionally statistically significant changes were seen in activity patterns and reflex immediately after exposure. Overall, it is probable that exposure to aerosolized VG and PG is a major problem. Although the number of vaping-related deaths in the US is rising, the specific cause remains unidentified. Therefore, determining what long-term effects vegetable glycerin (VG) and propylene glycol (PG), the main non-nicotine components in e-cigarettes, may have is crucial. Discovering that these components are harmful when tested on fruit flies (Drosophila melanogaster), a model organism, may suggest similar effects in humans. In this study, the number of offspring, changes in behavior, and phenotypic mutations in fruit flies were observed for the parent, F1, and F2 generations after the parent generation were exposed to one of four treatments of aerosolized solution. These included a 50% PG/50% VG, a 30% PG/70% VG, a 70% PG/30% VG, or no solution (control) using a nebulizer for 18 seconds each day, for two days. It was found that each experimental group had fewer offspring than the control. A two-sample T-test (α = 0.05) was used to find that the size of the flies in the F1 generation was statistically significantly smaller in ⅔ of the experimental groups when compared to the control. Furthermore, it was observed using a two-proportion Z-test (α = 0.05) that ⅔ of experimental groups in the parent generation, and all F1 experimental groups were statistically significantly more likely to develop at least one phenotypic mutation than the control. Additionally statistically significant changes were seen in activity patterns and reflex immediately after exposure. Overall, it is probable that exposure to aerosolized VG and PG is a major problem.

CFTR transmembrane segments are impaired in their conformational adaptability by a pathogenic loop mutation and dynamically stabilized by Lumacaftor

The cystic fibrosis transmembrane conductance regulator (CFTR) is an ion channel protein that is defective in individuals with cystic fibrosis (CF). To advance the rational design of CF therapies, it is important to elucidate how mutational defects in CFTR lead to its impairment and how pharmacological compounds interact with and alter CFTR. Here, using a helical-hairpin construct derived from CFTR's transmembrane (TM) helices 3 and 4 (TM3/4) and their intervening loop, we investigated the structural effects of a patient-derived CF-phenotypic mutation, E217G, located in the loop region of CFTR's membrane-spanning domain. Employing a single-molecule FRET assay to probe the folding status of reconstituted hairpins in lipid bilayers, we found that the E217G hairpin exhibits an altered adaptive packing behavior stemming from an additional GXXXG helix–helix interaction motif created in the mutant hairpin. This observation suggested that the misfolding and functional defects caused by the E217G mutation arise from an impaired conformational adaptability of TM helical segments in CFTR. The addition of the small-molecule corrector Lumacaftor exerts a helix stabilization effect not only on the E217G mutant hairpin, but also on WT TM3/4 and other mutations in the hairpin. This finding suggests a general mode of action for Lumacaftor through which this corrector efficiently improves maturation of various CFTR mutants.

Generation of a Mutant Population for TILLING Common Bean Genotype BAT 93

Common bean (Phaseolus vulgaris) is the major food legume worldwide, making it an important target for novel approaches of genetic analysis. This study evaluated the use of ethyl methane sulfonate (EMS) for the generation of a mutant population for targeted induced local lesions in genomes (TILLING) in common bean. TILLING is a powerful reverse genetics approach that uses a large mutant population for identification of mutants in loci of interest. Based on overall survival, development, and yield of treated seed, 40 mm EMS was found to be an appropriate concentration for the generation of a mutant population in common bean genotype BAT 93. Higher concentrations of EMS resulted in survival rates of less than 10% and lower concentrations resulted in the generation of fewer mutants. Based on TILLING results from other species, a population of 5000 lines is estimated to be sufficient for saturation of the common bean genome. Phenotypic mutation frequencies and the isolation of targeted mutations in the BAT 93 mutant population indicate that mutagenesis was effective.