The landscape of coadaptation in Vibrio parahaemolyticus
Abstract
Investigating fitness interactions in natural populations remains a considerable challenge. We take advantage of the unique population structure of Vibrio parahaemolyticus, a bacterial pathogen of humans and shrimp, to perform a genome-wide screen for coadapted genetic elements. We identified 90 interaction groups (IGs) involving 1,560 coding genes. 82 IGs are between accessory genes, many of which have functions related to carbohydrate transport and metabolism. Only 8 involve both core and accessory genomes. The largest includes 1,540 SNPs in 82 genes and 338 accessory genome elements, many involved in lateral flagella and cell wall biogenesis. The interactions have a complex hierarchical structure encoding at least four distinct ecological strategies. One strategy involves a divergent profile in multiple genome regions, while the others involve fewer genes and are more plastic. Our results imply that most genetic alliances are ephemeral but that increasingly complex strategies can evolve and eventually cause speciation.
Data availability
All data are publicly available.
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Vibrio parahaemolyticus Genome sequencing and assemblyNCBI Bioproject, PRJNA393608.
Article and author information
Author details
Funding
National Key Research & Development Program of China (No. 2017YFC1601503 and 2018YFC1603902)
- Yujun Cui
National Key Program for Infectious Diseases of China (No. 2018ZX10101003 and 2018ZX10714-002)
- Yujun Cui
Sanming Project of Medicine in Shenzhen (No. SZSM201811071)
- Yujun Cui
National Natural Science Foundation of China (No. ZDRW-ZS-2017-1)
- Yujun Cui
Medical Research Council (MR/M501608/1)
- Daniel Falush
Shanghai Municipal Science and Technology Major Project (2019SHZDZX02)
- Daniel Falush
Chinese Academy of Sciences 100 talents program
- Daniel Falush
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Cui et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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