Data from: Mitochondria and Wolbachia titers are positively correlated during maternal transmission

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 symbiont Wolbachia interacts with mitochondria during
maternal transmission. Mitochondria and Wolbachia may interact
antagonistically and compete as each population tries to ensure its own
evolutionary success. Alternatively, mitochondria and Wolbachia may
cooperate as both benefit from ensuring the fitness of the mother. We
characterized the relationship between mitochondria and Wolbachia titers
in ovaries of D. melanogaster. We found that mitochondria and Wolbachia
titers are positively correlated in common laboratory genotypes of D.
melanogaster. We attempted to perturb this covariation through the
introduction of Wolbachia variants 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: NADH dehydrogenase and a
mitochondrial transporter. Overall, we find that mitochondria and
Wolbachia titers are commonly positively correlated, but this positive
covariation is disrupted at high titers of Wolbachia. Our results suggest
that mitochondria and Wolbachia have likely evolved mechanisms to stably
coexist, but the competitive dynamics change at high Wolbachia titers. We
provide future directions to better understand how their interaction
influences the maintenance of the symbiosis.