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Intriguing parasites and intramembrane proteases.
1Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA. Rob.Rawson@UTSouthwestern.Edu
Genes & Development
|June 19, 2008
Summary
The rhomboid protease EhROM1 from Entamoeba histolytica cleaves cell surface lectins. This protease is crucial for amoebal infection, suggesting a role in receptor shedding.
Area of Science:
- Biochemistry
- Cell Biology
- Parasitology
Background:
- Rhomboid proteases are intramembrane-cleaving enzymes found across all kingdoms of life.
- Entamoeba histolytica is an important human pathogen responsible for amoebiasis.
Purpose of the Study:
- To investigate the function of the single proteolytic rhomboid (EhROM1) in Entamoeba histolytica.
- To determine the substrates and localization of EhROM1 during host-pathogen interactions.
Main Methods:
- Protease activity assays.
- Immunofluorescence microscopy to determine protein colocalization.
- Analysis of protein-protein interactions.
Main Results:
- EhROM1 cleaves cell surface galactose-binding or N-acetylgalactosamine-binding (Gal/Gal-NAc) lectins.
- EhROM1 and Gal/Gal-NAc lectins colocalize during phagocytosis and receptor capping.
- EhROM1 is localized at the base of the receptor cap, not within the cap itself.
Conclusions:
- EhROM1 plays a critical role in receptor shedding during Entamoeba histolytica infection.
- The localization of EhROM1 suggests a mechanism for regulating cell surface receptors essential for parasitic invasion.
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