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Enteric Bacterial Invasion Of Intestinal Epithelial Cells In Vitro Is Dramatically Enhanced Using a Vertical Diffusion Chamber Model
Published on: October 22, 2013
Vertical and horizontal transmission drive bacterial invasion
Natacha Kremer1, Martinus E Huigens
1Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, USA. natacha.kremer@normalesup.org
Molecular Ecology
|September 3, 2011
Summary
Horizontal transmission of Wolbachia bacteria, a reproductive manipulator, was key in spreading through the wasp Leptopilina clavipes. This study provides the first evidence for within-species horizontal spread of Wolbachia infections.
Area of Science:
- Microbiology
- Evolutionary Biology
- Genetics
Background:
- Wolbachia bacteria are endosymbionts infecting many arthropods, manipulating host reproduction for transmission.
- Both vertical (mother-to-offspring) and horizontal (contagion) transmission routes for Wolbachia are known.
- The role of within-species horizontal transmission in the initial spread of Wolbachia infections remained unclear.
Purpose of the Study:
- To investigate the role of horizontal transmission in the early spread of Wolbachia within the parasitoid wasp Leptopilina clavipes.
- To determine if a single Wolbachia strain was responsible for the observed infection pattern.
Main Methods:
- Analysis of genetic variation in host nuclear DNA, mitochondrial DNA, and Wolbachia DNA.
- Examination of potential associations between the diversity patterns of these genetic markers.
Main Results:
- No genetic diversity was found in Wolbachia genes, indicating a single infecting strain.
- A correlation between variations in host mitochondrial and nuclear DNA suggests significant horizontal transmission.
- This horizontal transfer likely played a crucial role in the current clonal genetic variation within the L. clavipes population.
Conclusions:
- Horizontal transmission is a significant factor in the early spread of Wolbachia infections within arthropod populations.
- The findings highlight the importance of host ecology, such as resource sharing in parasitoid wasps, in facilitating symbiont spread.
- This study provides critical insights into the co-evolutionary dynamics between Wolbachia and its hosts.
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