A frameshift in Yersinia pestis rcsD alters canonical Rcs signalling to preserve flea-mammal plague transmission cycles
Abstract
Multiple genetic changes in the enteric pathogen Yersinia pseudotuberculosis have driven the emergence of Yesinia pestis, the arthropod-borne, etiological agent of plague. These include developing the capacity for biofilm-dependent blockage of the flea foregut to enable transmission by flea bite. Previously, we showed that pseudogenisation of rcsA, encoding a component of the Rcs signalling pathway, is an important evolutionary step facilitating Y. pestis flea-borne transmission. Additionally, rcsD, another important gene in the Rcs system, harbours a frameshift mutation. Here, we demonstrated that this rcsD mutation resulted in production of a small protein composing the C-terminal RcsD histidine-phosphotransferase domain (designated RcsD-Hpt) and full-length RcsD. Genetic analysis revealed that the rcsD frameshift mutation followed the emergence of rcsA pseudogenisation. It further altered the canonical Rcs phosphorylation signal cascade, fine-tuning biofilm production to be conducive with retention of the pgm locus in modern lineages of Y. pestis. Taken together, our findings suggest that a frameshift mutation in rcsD, is an important evolutionary step that fine-tuned biofilm production to ensure perpetuation of flea-mammal plague transmission cycles.
Data availability
All data is available within the paper, its Supporting Information files, and the NCBI GenBank. RNA-seq sequencing data can be accessed in NCBI GenBank using BioProject ID: PRJNA876755.Source data files have been provided for Figures 2D, 4B, 4D, Figures 2- figure supplement 1F and 1G.
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Differential expression of Y. pestis genes in Y. pestis mutant strains growing at 26 degrees C and 37 degrees CNCBI Sequence Read Archive, PRJNA876755.
Article and author information
Author details
Funding
National Major Science and Technology Projects of China (2022YFC2303202)
- Xiao-Peng Guo
National Natural Science Foundation of China (31700072)
- Xiao-Peng Guo
National Natural Science Foundation of China (31670139)
- Yi-Cheng Sun
National Natural Science Foundation of China (31800120)
- Hai-Qin Yan
the Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences (Project 2019HY310001)
- Yi-Cheng Sun
the CAMS Innovation Fund for Medical Sciences (Project 2021-I2M-1-043)
- Yi-Cheng Sun
fundamental Research Funds for the Central University (3332021092)
- Yi-Cheng Sun
NIH Research Project Grant (R01AI117016-01A1)
- Viveka Vadyvaloo
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Joseph T Wade, New York State Department of Health, United States
Ethics
Animal experimentation: The animal study of flea blockage, related to Figure 5A, 5B and 5C, was performed in strict accordance with the U.S. National Institutes of Health (NIH) Guide for the Care and Use of Laboratory Animals (National Research Council Committee for the Update of the Guide for the and Use of Laboratory, 2011) and as approved by the Washington State University Institutional Animal Care and Use Committee, under the Animal Subject Approval Form (ASAF) 6641 and 6396.The animal study of murine infection, related to Figure 6A, 6B and 6C, was performed in strict accordance to the Guidelines for the Welfare and Ethics of Laboratory Animals of China and all the animal experiments were approved by the Institutional Animal Care Committee (IACUC) of Academy of Military Medical Sciences (AMMS), ethical approval number IACUC-DWZX-2021-057.
Version history
- Received: October 4, 2022
- Preprint posted: October 25, 2022 (view preprint)
- Accepted: April 2, 2023
- Accepted Manuscript published: April 3, 2023 (version 1)
- Version of Record published: May 17, 2023 (version 2)
Copyright
© 2023, Guo 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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