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Updated: May 19, 2026
10:35
Markerless Gene Deletion by Floxed Cassette Allelic Exchange Mutagenesis in Chlamydia trachomatis
Published on: January 30, 2020
Chlamydiae assemble a pathogen synapse to hijack the host endoplasmic reticulum.
Maud Dumoux1, Daniel K Clare, Helen R Saibil
1Institute of Structural and Molecular Biology, Birkbeck & University College London, Malet Street, London, WC1E 7HX, UK.
Traffic (Copenhagen, Denmark)
|August 21, 2012
Summary
Chlamydia bacteria hijack the host endoplasmic reticulum (ER) to form their protective inclusion. This pathogen-controlled process is essential for bacterial survival and replication, involving direct ER-bacteria connections.
Area of Science:
- Microbiology
- Cell Biology
- Pathogen-Host Interactions
Background:
- Chlamydiae are obligate intracellular bacteria residing in a membrane-bound inclusion.
- The inclusion membrane's interaction with host organelles and its origin are poorly understood.
- Understanding these interactions is key to deciphering Chlamydia pathogenesis.
Purpose of the Study:
- To investigate the relationship between the Chlamydia inclusion membrane and host cellular organelles.
- To determine the role of the endoplasmic reticulum (ER) in Chlamydia infection.
- To elucidate the mechanism of inclusion biogenesis and its dependence on host factors.
Main Methods:
- Immunofluorescence microscopy and electron tomography to visualize host-pathogen interactions.
- Analysis of protein localization and translocation between the ER and inclusion.
- Functional assays assessing the impact of ER manipulation on Chlamydia development.
Main Results:
- The host endoplasmic reticulum (ER), particularly rough ER (rER), is specifically recruited to the Chlamydia inclusion.
- Key rER proteins are enriched on and translocated into the inclusion membrane.
- ER recruitment is orchestrated by Chlamydia and occurs independently of host trafficking.
- ER integrity is crucial for inclusion development; ER vacuolation stalls growth, while disruption causes inclusion bursting.
- Pathogen synapses' form at rER contact sites, linking chlamydial secretion complexes to the inclusion membrane.
Conclusions:
- Chlamydia actively hijacks the host ER to establish and maintain its inclusion.
- The ER provides essential components and structural support for the inclusion membrane.
- This study reveals a sophisticated supramolecular assembly for pathogen manipulation of a host organelle.
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