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Title: A male-killing Wolbachia endosymbiont is concealed by another endosymbiont and a nuclear suppressor
Bacteria that live inside the cells of insect hosts (endosymbionts) can alter the reproduction of their hosts, including the killing of male offspring (male killing, MK). MK has only been described in a few insects, but this may reflect challenges in detecting MK rather than its rarity. Here, we identify MK Wolbachia at a low frequency (around 4%) in natural populations of Drosophila pseudotakahashii . MK Wolbachia had a stable density and maternal transmission during laboratory culture, but the MK phenotype which manifested mainly at the larval stage was lost rapidly. MK Wolbachia occurred alongside a second Wolbachia strain expressing a different reproductive manipulation, cytoplasmic incompatibility (CI). A genomic analysis highlighted Wolbachia regions diverged between the 2 strains involving 17 genes, and homologs of the wmk and cif genes implicated in MK and CI were identified in the Wolbachia assembly. Doubly infected males induced CI with uninfected females but not females singly infected with CI-causing Wolbachia . A rapidly spreading dominant nuclear suppressor genetic element affecting MK was identified through backcrossing and subsequent analysis with ddRAD SNPs of the D . pseudotakahashii genome. These findings highlight the complexity of nuclear and microbial components affecting MK endosymbiont detection and dynamics in populations and the challenges of making connections between endosymbionts and the host phenotypes affected by them.  more » « less
Award ID(s):
2145195
NSF-PAR ID:
10405109
Author(s) / Creator(s):
; ; ; ; ;
Editor(s):
Malik, Harmit S.
Date Published:
Journal Name:
PLOS Biology
Volume:
21
Issue:
3
ISSN:
1545-7885
Page Range / eLocation ID:
e3001879
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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