Data from: Live imaging of symbiosis: spatiotemporal infection dynamics of GFP-labeled Burkholderia symbiont in the bean bug Riptortus pedestris

Many insects possess endosymbiotic bacteria inside their body, wherein intimate interactions occur between the symbiotic partners. While recent technological advancements have deepened our understanding of metabolic and evolutionary features of the symbiont genomes, molecular mechanisms underpinning the intimate interactions remain difficult to approach because the insect symbionts are generally uncultivable. The bean bug Riptortus pedestris is associated with the betaproteobacterial Burkholderia symbiont in a posterior region of the midgut, which develops numerous crypts harboring the symbiont cells extracellularly. Distinct from other insect symbiotic systems, the bean bug acquires the Burkholderia symbiont not by vertical transmission but from environment every generation. By making use of the cultivability and the genetic tractability of the symbiont, we constructed a transgenic Burkholderia strain labeled with green fluorescent protein (GFP), which enabled detailed observation of spaciotemporal dynamics and colonization process of the symbiont in freshly-prepared specimens. The symbiont live imaging revealed that, at the second instar, colonization to the symbiotic midgut M4 region started around 6 h after inoculation (hai). By 24 hai, the symbiont cells appeared in the main tract and also in several crypts of the M4 region. By 48 hai, most of the crypts were colonized by the symbiont cells. By 72 hai, all the crypts were filled up with the symbiont cells, which continued during the subsequent nymphal development. Quantitative PCR of the symbiont confirmed the infection dynamics quantitatively. These results highlight the stinkbug-Burkholderia gut symbiotic system as an unprecedented model for comprehensive understanding of molecular mechanisms underpinning insect symbiosis.