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bioRxiv · 10.1101/2021.01.13.425146

Aedes aegypti Aag-2 culture cells enter endoreplication process upon pathogen challenge

Abstract

Metamorphic insects apparently rely on a finite number of cells after emergence to counterbalance either commensal and pathogen presence. For hematophagous insects, blood-feeding is a crucial step for offspring development, therefore enteric cells repairing molecular mechanisms consists in fine regulated pathways to counterattack biotic and abiotic insults. Nevertheless, recent research suggests that midgut cells are capable to adapt their immune responses to pathogen challenges. Recently, Anopheles and Aedes mosquitoes have been observed to increase their DNA cell content upon encounter with parasites, bacteria and virus respectively. Genomic endoreplication is one of the most important processes in larval development for fast transcriptional activity and protein secretion. So, in this paper we explore the ability of Aedes aegypti Aag-2 culture cells to develop a likely endoreplication process to face pathogen presence. Aag-2 cells at 6 and 12 hours post-biotic insult enter a proliferation arrest and increases DNA content, these two phenomena recovers control levels at 24 h post-treatment. It requires more research data about the type of genomic regions that has been replicated in the process, and the concentration that antimicrobial molecules are released into culture media.

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Dominguez-Benitez, C., Serrato-Salas, J., Conde, R., Lanz-Mendoza, H.. 2021-01-13. Aedes aegypti Aag-2 culture cells enter endoreplication process upon pathogen challenge. https://doi.org/10.1101/2021.01.13.425146

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