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Title: microRNA regulation in an ancient obligate endosymbiosis

Although many insects are associated with obligate bacterial endosymbionts, the mechanisms by which these host/endosymbiont associations are regulated remain mysterious. While microRNAs (miRNAs) have been recently identified as regulators of host/microbe interactions, including host/pathogen and host/facultative endosymbiont interactions, the role miRNAs may play in mediating host/obligate endosymbiont interactions is virtually unknown. Here, we identified conserved miRNAs that potentially mediate symbiotic interactions between aphids and their obligate endosymbiont,Buchnera aphidicola. Using smallRNAsequence data fromMyzus persicaeandAcyrthosiphon pisum, we annotated 93M. persicaeand 89A. pisummiRNAs, among which 69 were shared. We found 14 miRNAs that were either highly expressed in aphid bacteriome, theBuchnera‐housing tissue, or differentially expressed in bacteriome vs. gut, a non‐Buchnera‐housing tissue. Strikingly, 10 of these 14 miRNAs have been implicated previously in other host/microbe interaction studies. Investigating the interaction networks of these miRNAs using a custom computational pipeline, we identified 103 miRNA::mRNAinteractions shared betweenM. persicaeandA. pisum. Functional annotation of the sharedmRNAtargets revealed only two over‐represented cluster of orthologous group categories: amino acid transport and metabolism, and signal transduction mechanisms. Our work supports a role for miRNAs in mediating host/symbiont interactions between aphids and their obligate endosymbiontBuchnera. In addition, our results highlight the probable importance of signal transduction mechanisms to host/endosymbiont coevolution.

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Author(s) / Creator(s):
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Date Published:
Journal Name:
Molecular Ecology
Page Range / eLocation ID:
p. 1777-1793
Medium: X
Sponsoring Org:
National Science Foundation
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