Regulatory framework of genome-edited products - a review / 生物工程学报

Genome editing is a genetic engineering technique that uses site-directed cleavage activity of specific artificial nucleases and endogenous DNA damage repair activity to generate insertions, deletions or substitutions in the targeted genomic loci. As the accuracy and efficiency of genome editing is improving and the operation is simple, the application of genome editing is expanding. This article provides an overview of the three major genome editing technologies and genome editing types, and the regulatory frameworks for genome-edited products were summarized in the United States, the European Union, and other countries. At the same time, based on the Chinese safety management principles and systems for genetically modified organisms (GMOs), the authors proposed a regulatory framework for genome-edited products. Genome-edited products should first be classified according to whether containing exogenous genetic components such as Cas9 editing enzymes or not. They should be regulated as traditional genetically modified organisms if they do. Otherwise, the regulation of genome-edited products depends on targeted modifications.

Advances in targeted replacement genome editing in plants / 生物工程学报

Targeted replacement genome editing refers to DNA modification and engineering technology that could induce and achieve mutations of targeted gene replacement or knockin at a target gene or DNA region. In this review, the principles, implementation methods, factors that influence efficiency and accuracy, and applications of gene replacement editing were summarized and discussed. It provides the reference for gene functional characterization and genetic improvements through gene replacement strategies in higher plant especially crops.

Effect of salinity and temperature on motility of Vibrio parahaemolyticus / 军事医学

Objective To investigate the effect of salinity and temperature on motility of Vibrio parahaemolyticus. Methods V.parahaemolyticus was inoculated on swarming or swimming agar plates containing different amounts of salinity (0.5%, 1.0%, 2.0%, and 4.0% NaCl, respectively), followed by incubation at 26 or 37℃, before the diameters of bacterial lawns were measured .Results and Conclusion The swarming motility was not affected by salinity , while the swimming motility was positively correlated with salinity .Maximum swimming occurred in 2.0% NaCl, and displayed a slight decline in salinity of 4.0%.Both swimming and swarming were affected by temperature , and the motility was signifi-cantly enhanced in 37℃vs 26℃.These results indicate that both salinity and temperature can modulate the motility of V. parahaemolyticus.

ASSESSMENT OF IRON BIOAVAILABILITY OF IRON BIOFORTIFIED MAIZE USING IN VITRO DIGESTION/CACO-2 CELL CULTURE MODEL / 营养学报

Objective To assess iron bioavailability of three iron-biofortified maizes using an in vitro digestion/ Caco-2 cell culture model. Method Three maize varieties rich in iron (Zhongtie 2, 3 and 4) and two maize varieties with lower content of iron (Zhengda 818 and 619) were pulverized, and the content of iron and phosphorus in each maize variety was measured. After digestion the iron bioavailability per g food was determined by using Caco-2 cell ferritin formation per mg cell protein as indicator. Results The iron content (33.250 mg/kg), iron bioavailability and the iron bioavailability per g food of Zhongtie 2 maize was the highest among all varieties, but its phosphorus content was lower. The maize varieties with the next higher iron bioavailability were Zhongtie 3 and Zhengda 818, and the lowest was Zhengda 619. Conclusion Zhongtie 2 maize contained the hightest content and bioavailability of iron,so it was optimal to use for the following human trials.