Genome Sequencing
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PI: Yasuko Rikihisa

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Contact Info:
 Dept. of Veterinary
 The Ohio State Univ.
 1925 Coffey Road
 Columbus, OH 43210
 Phone: 614-292-5661
OSU Homepage
Dept. of Vet. Biosciences

    Welcome to the Molecular, Cellular, and Environmental Rickettsiology Research Laboratory.

    Ehrlichia, Anaplasma, and Neorickettsia are unique bacteria (obligatory intracellular bacteria) that infect leukocytes, and cause a severe flu-like disease collectively called “Ehrlichiosis”. Our research program embraces “from genomes to animal models” and “from field to molecular works”: to analyze these bacterial genomes; to investigate suspected bacterial virulence factors and signaling mechanisms in vitro; to analyze molecular mechanisms of ehrlichial transmission from vectors to mammals; and test putative disease mechanisms in cultured cells and in relevant animal models, and improve diagnostic methods.


Current Research Projects:

  • Elucidation of Signaling Pathways for Entry and Survival of Ehrlichiae in Leukocytes: The objective of this project is to study bacterial molecules that drive safe entry and survival of  ehrlichiae in the host cells by mobilizing actin cytoskeleton, inhibiting reactive oxygen species generation, lysosomal fusion, and leukocyte’s activation and apoptosis, and by competitively acquiring cholesterol, and nutrients by inducing autophagy.
  • Characterization of Type IV Secretion and Two-Component Regulatory Systems in Human Ehrlichiosis Agent: The objectives of this project are 1) to examine the functions and effectors of type IV secretion system in ehrlichial infection, 2) to elucidate molecular mechanisms by which three pairs of functional two-component systems (CckA-CtrA, NtrY-NtrX, and PleC-PleD) regulate ehrlichial intracellular growth and developmental cycle.
  • Roles of Ehrlichial Outer Membrane Proteins in Parasitism: The objective of this project is to examine biological activities of unique outer membrane proteins for invasion and bacterial physiology (porin, iron transport), and host signal transduction and immune modulation in a cell culture and an animal model of human ehrlichiosis.
  • Study Virulence Factors by Using Transposon Mutagenesis: The objective of this project has been to create Ehrlichia, Anaplasma, and Neorickettsia  transposon insertion mutants to study their virulence and pathogenesis in animal models of disease.

    We are always looking for exceptionally talented and motivated new members (grad students and postdocs). To apply, email a CV to Dr. Rikihisa. Graduate students can apply through the four graduate programs at the Ohio State University:

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Last Updated: February 7, 2022 | Maintained by: Mingqun Lin | © OSU Rickettsiology Lab, 2001 - 2024.

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