The overall goal of this proposal is to identify novel host signaling components that are targeted during infection of the gut by the gastrointestinal pathogen Vibrio parahaemolyticus. V. parahaemolyticus is a major agent responsible for gastroenteritis outbreaks associated with the consumption of contaminated seafood found in both the Pacific and Atlantic oceans. Understanding how pathogens disrupt normal homeostasis and cripple the host defense response is critical for our understanding of signaling pathways utilized by gastrointestinal cells. Recent sequencing of the V. parahaemolyticus genome has revealed the presence of a pathogenicity island (PAII) that encodes a number of toxins, a type III secretion system (TTSS), one recognizable effector, VopA, and a number of other uncharacterized open reading frames thought to encode novel effectors. Previous studies on effectors demonstrate that these proteins have evolved by capturing or mimicking eukaryotic regulatory functions that are critical for host cell regulation. The discovery of the mechanism utilized by each of these effectors has provided insights into the essential mechanisms of eukaryotic cellular signaling. Our initial studies have focused on the characterization of the effector VopA that belongs to the YopJ-like family of virulence factors. We are using VopA as a representative effector from V. parahaemolyticus to design a system for analysis of unknown effectors encoded within PAII. By identifying the novel virulence factors expressed by V. parahaemolyticus and revealing their targets in a eukaryotic cell, we will uncover new critical components of host signaling pathways. This grant will be used to fund research involved in developing an in vitro V. parahaemolyticus infection system to study pathogenic effectors produced by a gram-negative marine bacterium that is responsible for causing food poisoning worldwide. Results from this application will be used as preliminary data for the submission of a future RO1 application. ? ? ?

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21DK072134-02
Application #
7140264
Study Section
Special Emphasis Panel (ZRG1-IDM-A (90))
Program Officer
Hamilton, Frank A
Project Start
2005-08-01
Project End
2008-07-31
Budget Start
2006-08-01
Budget End
2008-07-31
Support Year
2
Fiscal Year
2006
Total Cost
$190,418
Indirect Cost
Name
University of Texas Sw Medical Center Dallas
Department
Biochemistry
Type
Schools of Medicine
DUNS #
800771545
City
Dallas
State
TX
Country
United States
Zip Code
75390
Broberg, Christopher A; Orth, Kim (2010) Tipping the balance by manipulating post-translational modifications. Curr Opin Microbiol 13:34-40
Burdette, Dara L; Seemann, Joachim; Orth, Kim (2009) Vibrio VopQ induces PI3-kinase-independent autophagy and antagonizes phagocytosis. Mol Microbiol 73:639-49
Burdette, Dara L; Yarbrough, Melanie L; Orth, Kim (2009) Not without cause: Vibrio parahaemolyticus induces acute autophagy and cell death. Autophagy 5:100-2
Hao, Yi-Heng; Wang, Yong; Burdette, Dara et al. (2008) Structural requirements for Yersinia YopJ inhibition of MAP kinase pathways. PLoS One 3:e1375
Burdette, Dara L; Yarbrough, Melanie L; Orvedahl, Anthony et al. (2008) Vibrio parahaemolyticus orchestrates a multifaceted host cell infection by induction of autophagy, cell rounding, and then cell lysis. Proc Natl Acad Sci U S A 105:12497-502
Trosky, Jennifer E; Liverman, Amy D B; Orth, Kim (2008) Yersinia outer proteins: Yops. Cell Microbiol 10:557-65
Mukherjee, Sohini; Negi, Veera S; Keitany, Gladys et al. (2008) In vitro activation of the IkappaB kinase complex by human T-cell leukemia virus type-1 Tax. J Biol Chem 283:15127-33
Mukherjee, Sohini; Orth, Kim (2008) In vitro signaling by MAPK and NFkappaB pathways inhibited by Yersinia YopJ. Methods Enzymol 438:343-53
Laskowski-Arce, Michelle A; Orth, Kim (2007) The elusive activity of the Yersinia protein kinase A kinase domain is revealed. Trends Microbiol 15:437-40
Liverman, Amy D B; Cheng, Hui-Chun; Trosky, Jennifer E et al. (2007) Arp2/3-independent assembly of actin by Vibrio type III effector VopL. Proc Natl Acad Sci U S A 104:17117-22

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