Aedes fluviatilis cell lines as new tools to study metabolic and immune interactions in mosquito-Wolbachia symbiosis

Christiano Calixto Conceição,Katia C Gondim,Carlos Logullo,Pedro Lagerblad De Oliveira,Angélica Arcanjo,Leonardo Araujo De Abreu,Luciano Andrade Moreira,Renato Martins Da Silva,Bruno Moraes,Itabajara Da Silva Vaz,Cíntia Lopes Nogueira,Jhenifer Nascimento Da Silva,Stephanie Serafim De Carvalho

doi:10.1038/s41598-021-98738-7

Abstract

In the present work, we established two novel embryonic cell lines from the mosquito Aedes fluviatilis containing or not the naturally occurring symbiont bacteria Wolbachia, which were called wAflu1 and Aflu2, respectively. We also obtained wAflu1 without Wolbachia after tetracycline treatment, named wAflu1.tet. Morphofunctional characterization was performed to help elucidate the symbiont-host interaction in the context of energy metabolism regulation and molecular mechanisms of the immune responses involved. The presence of Wolbachia pipientis improves energy performance in A. fluviatilis cells; it affects the regulation of key energy sources such as lipids, proteins, and carbohydrates, making the distribution of actin more peripheral and with extensions that come into contact with neighboring cells. Additionally, innate immunity mechanisms were activated, showing that the wAflu1 and wAflu1.tet cells are responsive after the stimulus using Gram negative bacteria. Therefore, this work confirms the natural, mutually co-regulating symbiotic relationship between W. pipientis and A. fluviatilis, modulating the host metabolism and immune pathway activation. The results presented here add important resources to the current knowledge of Wolbachia-arthropod interactions.

Highlights

In the present work, we established two novel embryonic cell lines from the mosquito Aedes fluviatilis containing or not the naturally occurring symbiont bacteria Wolbachia, which were called wAflu[1] and Aflu[2], respectively
Partial sequencing of the mitochondrial 16S rRNA gene confirmed the cell lines belonged to Aedes fluviatilis species. wAflu[1] and Aflu[2] both showed complete identity with deposited transcriptomic 16S rRNA sequence (MW574133) from A. fluviatilis (Fig. 1A)
The relationship between symbiosis and some biological processes, such as carbohydrate and lipid metabolic regulation and immune responses, are difficult to study in vivo

Summary

Introduction

We established two novel embryonic cell lines from the mosquito Aedes fluviatilis containing or not the naturally occurring symbiont bacteria Wolbachia, which were called wAflu[1] and Aflu[2], respectively. Morphofunctional characterization was performed to help elucidate the symbiont-host interaction in the context of energy metabolism regulation and molecular mechanisms of the immune responses involved. The transinfection of the bacterium Wolbachia into insect hosts has been recently performed in order to elucidate the mechanisms of host-parasite interaction and potentially identify control alternatives for insect-borne d iseases[15]. It is well established that Wolbachia, as an obligate intracellular bacterium, can exhibit symbiont, parasitic, mutualistic, or commensal relationships with diverse insects, potentially affecting host fitness and/or causing reproductive aberrations to enhance their own transmission[1,24]. New models to study the interaction between Wolbachia and its hosts can shed new light on the biological mechanisms of this complex relationship

Methods

Results

Conclusion