Tan Anjiang

Genome Editing Technologies and Its Application in Insects

Genome editing technologies are important for functional genomics study and application. Zinc finger nucleases (ZFNs), transcription activitor-like effector nucleases (TALENs) and clustered regularly interspaced short palindromic repeats/CRISPR associated protein (CRISPR/Cas) system are three major genome editing technologies established in recent years. Mutagenesis induced by these three techniques is mainly through making double strand break (DSB) at a specific site and followed by DSB repair process. ZFNs is the first established genome editing technology which could be used to operate site-specific knock out and knock in. However, the ZFNs technology suffers from construction complexity, high cost and other problems. The TALENs technology, which was developed based on the ZFNs technology, is much better than ZFNs technology for higher flexibility and lower cost. The CRISPR/Cas system is different from ZFNs and TALENs technologies for its unique targeting mechanism which makes this technology more suitable for multiplexed targeting. Until now, all these technologies have been successfully tested in a number of organisms, e.g., mouse, zebrafish, fruit fly, nematode, silkworm. These genome editing tools will play important roles in future functional genomics study in the post genome era.

Genetic Regulation of Insect Populations

Genetic regulation of insect populations is a powerful system. It is set up based on the integration of regulation of species specific target gene and sexual specified control elements through genetic transformation. The offsprings produced in the system will have normal males bringing female lethal or abnormal genes. With advantages of species specificity, eco-friendliness and high efficiency, genetic regulation technique (GRT) established with the insect sterile technique becomes a better choice for insect population control. So far, GRT has evolved into the new generation called ‘Release of Insect with Dominant Lethal (RIDL) from the primitive radiation caused sterility and succeeded in several insects. In this review, we introduce the history of GRT and related theories and methods, including the specific regulating elements, lethal or defect genes and the transgenic system. Some successful cases, such as mosquitos, silkworm and cotton bollworm are also listed. Finally, we discuss potential problems and the future of GRT.