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This content will become publicly available on November 1, 2025

Title: An intranuclear bacterial parasite of deep-sea mussels expresses apoptosis inhibitors acquired from its host
Abstract A limited number of bacteria are able to colonize the nuclei of eukaryotes. ‘CandidatusEndonucleobacter’ infects the nuclei of deep-sea mussels, where it replicates to ≥80,000 bacteria per nucleus and causes nuclei to swell to 50 times their original size. How these parasites are able to replicate and avoid apoptosis is not known. Dual RNA-sequencing transcriptomes of infected nuclei isolated using laser-capture microdissection revealed that ‘CandidatusEndonucleobacter’ does not obtain most of its nutrition from nuclear DNA or RNA. Instead, ‘CandidatusEndonucleobacter’ upregulates genes for importing and digesting sugars, lipids, amino acids and possibly mucin from its host. It likely prevents apoptosis of host cells by upregulating 7–13 inhibitors of apoptosis, proteins not previously seen in bacteria. Comparative phylogenetic analyses revealed that ‘Ca. Endonucleobacter’ acquired inhibitors of apoptosis through horizontal gene transfer from their hosts. Horizontal gene transfer from eukaryotes to bacteria is assumed to be rare, but may be more common than currently recognized.  more » « less
Award ID(s):
2003107 1934844
PAR ID:
10556404
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Nature Publishing Group
Date Published:
Journal Name:
Nature Microbiology
Volume:
9
Issue:
11
ISSN:
2058-5276
Page Range / eLocation ID:
2877 to 2891
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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