Introducing Exogenous DNA Vectors Directly into Trypoxylus dichotomus Larvae Via In Vivo Electroporation

Area of Science:

• Entomology
• Molecular Biology
• Genetics

Background:

• Gene function studies in Japanese rhinoceros beetles (Trypoxylus dichotomus) are limited by underdeveloped gain-of-function techniques and impractical germline transgenesis.
• Systemic larval RNA interference (RNAi) hinders the analysis of lethal genes due to its non-specific nature.

Purpose of the Study:

• To develop a simple, efficient protocol for introducing exogenous DNA into T. dichotomus larvae via in vivo electroporation.
• To enable rapid, tissue-specific gene function analysis in T. dichotomus, particularly for lethal genes.

Main Methods:

• Optimized procedures for adult breeding and egg collection in T. dichotomus.
• A parameterized in vivo electroporation technique delivering a piggyBac transposon vector into specific larval tissues.
• Utilized the T. dichotomus actinA3 promoter for reporter gene expression.

Main Results:

• Achieved mosaic expression of a reporter gene in T. dichotomus larvae within one day post-electroporation.
• Demonstrated the feasibility of rapid, tissue-specific functional analysis without establishing transgenic lines.
• The T. dichotomus actinA3 promoter showed effectiveness across diverse insect species.

Conclusions:

• The developed electroporation protocol is a valuable gain-of-function tool for T. dichotomus.
• This method is adaptable to other non-model insect species, broadening its applicability.
• Facilitates efficient genetic research in insects with long generation times or complex reproductive biology.