Chlamydia trachomatis is the leading cause of preventable blindness and the most commonly acquired sexually transmitted infection of bacterial origin, with over 4 million new cases in the United States and an estimated 92 million cases worldwide each year. Importantly, there are substantial ethnic and gender disparities associated with chlamydial infection, where the majority of undiagnosed chronic infections are subclinical in women and linked to an increased risk for developing pelvic inflammatory disease, infertility, cervical cancer, stillbirths, and premature deliveries.While the precise mechanisms responsible for these clinical manifestations remain largely undetermined, we do know that Chlamydial infections require establishment and maintenance of a unique intracellular replication niche for completion of a complex biphasic lifecycle. However, many of the host factors involved in this process are not known and this gap in our knowledge limits our understanding of the C. trachomatis lifecycle and pathogenesis associated Chlamydia infections. The long-term objective of our research is to determine the molecular mechanisms that Chlamydia employs to establish an infection. We hypothesize that C. trachomatis relies on a subset of genes in the human genome for successful completion of the bacterial lifecycle and knock-outs of these host genes will perturb the Chlamydia lifecycle and prevent cell death. To test this hypothesis, we are using a CRISPR-Cas9 based high- throughput genome wide knock-out screen to identify novel genes and microRNAs that are resistant to C. trachomatis infection. Additionally, we will generate individual gene knock-outs to investigate the role of specific host genes in the cytoskeleton and vesicle transport pathways. Specifically, this proposal aims to (1) identify mutations in genes or microRNAs that are essential for the C. trachomatis lifecycle (2) knockout individual genes in specific host pathways and determine their role in C. trachomatis entry and inclusion germination and maturation.

Public Health Relevance

Public health relevance: Chlamydia trachomatis is the leading cause of preventable blindness and there are more cases of Chlamydia reported to the CDC every year than all other infectious diseases combined. There are substantial ethnic and gender disparities associated with chlamydial infection, where the majority of undiagnosed chronic infections are subclinical in women and linked to an increased risk for developing pelvic inflammatory disease, infertility, cervical cancer, stillbirths, and premature deliveries.We anticipate that the results from this study will provide fundamental new insights that explain how C. trachomatis manipulates the human host cell and that these insights may lead to new treatment strategies.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21AI130670-02
Application #
9614249
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Vincent, Leah Rebecca
Project Start
2017-12-15
Project End
2019-11-30
Budget Start
2018-12-01
Budget End
2019-11-30
Support Year
2
Fiscal Year
2019
Total Cost
Indirect Cost
Name
Montana State University - Bozeman
Department
Microbiology/Immun/Virology
Type
Earth Sciences/Resources
DUNS #
625447982
City
Bozeman
State
MT
Country
United States
Zip Code
59717
Borges, Adair L; Zhang, Jenny Y; Rollins, MaryClare F et al. (2018) Bacteriophage Cooperation Suppresses CRISPR-Cas3 and Cas9 Immunity. Cell 174:917-925.e10