: Entamoeba histolytica infects approximately 1% of the world's population, and causes up to 100,000 deaths annually. The disease-causing trophozoite stage of the parasite differentiates into the infectious cyst form while within the host colon, and the stimuli that induce this differentiation are only now becoming clear. We had previously found that galactose-terminated molecules, including those in colonic mucus, are used by the trophozoites to form cellular aggregates just prior to cyst formation. We have now found that short chain fatty acids, which are produced by the resident colonic bacterial population, can regulate the Entamoeba cyst formation process in a concentration-dependent manner. The effects of short chain fatty acids on the parasites are different from the effects these compounds have on other cells of the host, but they may be working through similar molecular mechanisms. This project will examine the mechanism(s) whereby these compounds regulate cyst formation, and will determine the extent of the effects these compounds have on gene and protein expression in the parasite.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
2R01AI044893-05A1
Application #
6967055
Study Section
Pathogenic Eukaryotes Study Section (PTHE)
Program Officer
Rogers, Martin J
Project Start
2000-03-01
Project End
2010-01-31
Budget Start
2005-05-15
Budget End
2006-01-31
Support Year
5
Fiscal Year
2005
Total Cost
$359,125
Indirect Cost
Name
New York University
Department
Microbiology/Immun/Virology
Type
Schools of Medicine
DUNS #
121911077
City
New York
State
NY
Country
United States
Zip Code
10016
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Byers, Jennifer; Eichinger, Daniel (2008) Acetylation of the Entamoeba histone H4 N-terminal domain is influenced by short-chain fatty acids that enter trophozoites in a pH-dependent manner. Int J Parasitol 38:57-64
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Byers, Jennifer; Eichinger, Daniel (2005) Entamoeba invadens: restriction of ploidy by colonic short chain fatty acids. Exp Parasitol 110:203-6
Byers, Jennifer; Faigle, Wolfgang; Eichinger, Daniel (2005) Colonic short-chain fatty acids inhibit encystation of Entamoeba invadens. Cell Microbiol 7:269-79
Frederick, Jesse; Eichinger, Dan (2004) Entamoeba invadens contains the components of a classical adrenergic signaling system. Mol Biochem Parasitol 137:339-43
Coppi, Alida; Merali, Salim; Eichinger, Daniel (2002) The enteric parasite Entamoeba uses an autocrine catecholamine system during differentiation into the infectious cyst stage. J Biol Chem 277:8083-90
Eichinger, D (2001) Encystation in parasitic protozoa. Curr Opin Microbiol 4:421-6