Transcriptomic Analysis of Steinernema Nematodes Highlights Metabolic Costs Associated to Xenorhabdus Endosymbiont Association and Rearing Conditions
AffiliationSchool of Animal and Comparative Biomedical Sciences, University of Arizona
MetadataShow full item record
PublisherFrontiers Media S.A.
CitationLefoulon, E., McMullen, J. G., & Stock, S. P. (2022). Transcriptomic Analysis of Steinernema Nematodes Highlights Metabolic Costs Associated to Xenorhabdus Endosymbiont Association and Rearing Conditions. Frontiers in Physiology.
JournalFrontiers in Physiology
RightsCopyright © 2022 Lefoulon, McMullen and Stock. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY).
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at email@example.com.
AbstractEntomopathogenic nematodes of the genus Steinernema have a mutualistic relationship with bacteria of the genus Xenorhabdus and together they form an antagonist partnership against their insect hosts. The nematodes (third-stage infective juveniles, or IJs) protect the bacteria from the external environmental stressors and vector them from one insect host to another. Xenorhabdus produce secondary metabolites and antimicrobial compounds inside the insect that protect the cadaver from soil saprobes and scavengers. The bacteria also become the nematodes’ food, allowing them to grow and reproduce. Despite these benefits, it is yet unclear what the potential metabolic costs for Steinernema IJs are relative to the maintenance and vectoring of Xenorhabdus. In this study, we performed a comparative dual RNA-seq analysis of IJs of two nematode-bacteria partnerships: Steinernema carpocapsae-Xenorhabdus nematophila and Steinernema. puntauvense-Xenorhbdus bovienii. For each association, three conditions were studied: (1) IJs reared in the insect (in vivo colonized), (2) colonized IJs reared on liver-kidney agar (in vitro colonized), and (3) IJs depleted by the bacteria reared on liver-kidney agar (in vitro aposymbiotic). Our study revealed the downregulation of numerous genes involved in metabolism pathways, such as carbohydrate, amino acid, and lipid metabolism when IJs were reared in vitro, both colonized and without the symbiont. This downregulation appears to impact the longevity pathway, with the involvement of glycogen and trehalose metabolism, as well as arginine metabolism. Additionally, a differential expression of the venom protein known to be secreted by the nematodes was observed when both Steinernema species were depleted of their symbiotic partners. These results suggest Steinernema IJs may have a mechanism to adapt their virulence in absence of their symbionts. Copyright © 2022 Lefoulon, McMullen and Stock.
NoteOpen access journal
VersionFinal published version
Except where otherwise noted, this item's license is described as Copyright © 2022 Lefoulon, McMullen and Stock. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY).