Protocol to establish a genetically tractable synthetic symbiosis between Sodalis praecaptivus and grain weevils by insect egg microinjection

Summary

We present a protocol to establish a synthetic symbiosis between the mCherry-expressing Sodalis praecaptivus and the grain weevil host, Sitophilus zeamais. We describe steps to isolate grain weevil eggs, followed by microinjecting the bacterial symbiont into insect eggs using a modified Drosophila injection protocol, which leads to localization of bacteria in female insect ovaries. We then detail larval transplantation and visualization of bacteria in live insects using a fluorescence dissection microscope to assess the transgenerational transmission to offspring in weevils.

For complete details on the use and execution of this protocol, please refer to Su et al. (2022). ¹

Graphical abstract

Highlights

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  Protocol for the establishment of synthetic symbiosis in grain weevils

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  Procedures to inject fluorescently labeled bacterial cells into grain weevil eggs

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  Steps for larval transplantation and visualization of bacteria in live insects

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  Provides a platform to study insect-bacterial interactions

Abstract

Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.

Abstract

We present a protocol to establish a synthetic symbiosis between the mCherry-expressing Sodalis praecaptivus and the grain weevil host, Sitophilus zeamais. We describe steps to isolate grain weevil eggs, followed by microinjecting the bacterial symbiont into insect eggs using a modified Drosophila injection protocol, which leads to localization of bacteria in female insect ovaries. We then detail larval transplantation and visualization of bacteria in live insects using a fluorescence dissection microscope to assess the transgenerational transmission to offspring in weevils.