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bioRxiv · 10.1101/2022.05.11.491587

MicroRNAs contribute to the host response to Coxiella burnetii

Sachan, M.·Brann, K. R.·Voth, D. E.·Raghavan, R.
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Abstract

MicroRNAs (miRNAs), a class of small non-coding RNAs, are critical to gene regulation in eukaryotes. They are involved in modulating a variety of physiological processes, including the host response to intracellular infections. Little is known about miRNA functions during infection by Coxiella burnetii, the causative agent of human Q fever. This bacterial pathogen establishes a large replicative vacuole within macrophages by manipulating host processes such as apoptosis and autophagy. We investigated miRNA expression in C. burnetii-infected macrophages and identified several miRNAs that were down- or up-regulated during infection. We further explored the functions of miR-143-3p, an miRNA whose expression is down-regulated in macrophages infected with C. burnetii, and show that increasing the abundance of this miRNA in human cells results in increased apoptosis and reduced autophagy - conditions that are unfavorable to C. burnetii intracellular growth. In sum, this study demonstrates that C. burnetii infection elicits a robust miRNA-based host response, and because miR-143-3p promotes apoptosis and inhibits autophagy, down-regulation of miR-143-3p expression during C. burnetii infection likely benefits the pathogen.

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Sachan, M., Brann, K. R., Voth, D. E., Raghavan, R.. 2022-05-12. MicroRNAs contribute to the host response to Coxiella burnetii. https://doi.org/10.1101/2022.05.11.491587

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