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Title: Mitochondria and Wolbachia titers are positively correlated during maternal transmission
Abstract

Mothers provide their offspring with symbionts. Maternally transmitted, intracellular symbionts must disperse from mother to offspring with other cytoplasmic elements, like mitochondria. Here, we investigated how the intracellular symbiontWolbachiainteracts with mitochondria during maternal transmission. Mitochondria andWolbachiamay interact antagonistically and compete as each population tries to ensure its own evolutionary success. Alternatively, mitochondria andWolbachiamay cooperate as both benefit from ensuring the fitness of the mother. We characterized the relationship between mitochondria andWolbachiatiters in ovaries ofDrosophila melanogaster. We found that mitochondria andWolbachiatiters are positively correlated in common laboratory genotypes ofD. melanogaster. We attempted to perturb this covariation through the introduction ofWolbachiavariants that colonize at different titers. We also attempted to perturb the covariation through manipulating the female reproductive tract to disrupt maternal transmission. Finally, we also attempted to disrupt the covariation by knocking down gene expression for two loci involved in mitochondrial metabolism:NADHdehydrogenase and a mitochondrial transporter. Overall, we find that mitochondria andWolbachiatiters are commonly positively correlated, but this positive covariation is disrupted at high titers ofWolbachia. Our results suggest that mitochondria andWolbachiahave likely evolved mechanisms to stably coexist, but the competitive dynamics change at highWolbachiatiters. We provide future directions to better understand how their interaction influences the maintenance of the symbiosis.

 
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NSF-PAR ID:
10080777
Author(s) / Creator(s):
 ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Molecular Ecology
Volume:
27
Issue:
11
ISSN:
0962-1083
Page Range / eLocation ID:
p. 2634-2646
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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