Open AccessEntamoeba histolytica modulates a complex repertoire of novel genes in response to oxidative and nitrosative stresses: implications for amebic pathogenesis
Author(s) -
Vicente João B.,
Ehrenkaufer Gretchen M.,
Saraiva Lígia M.,
Teixeira Miguel,
Singh Upinder
Publication year - 2009
Publication title -
cellular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.542
H-Index - 138
eISSN - 1462-5822
pISSN - 1462-5814
DOI - 10.1111/j.1462-5822.2008.01236.x
Subject(s) - entamoeba histolytica , biology , gene , oxidative stress , gene expression , microbiology and biotechnology , reactive oxygen species , genome , genetics , dna microarray , phenotype , regulation of gene expression , biochemistry
Summary Upon host infection, the protozoan parasite Entamoeba histolytica is confronted with reactive oxygen and nitrogen species and must survive these stresses in order to cause invasive disease. We analysed the parasite's response to oxidative and nitrosative stresses, probing the transcriptional changes of trophozoites of a pathogenic strain after a 60 min exposure to H 2 O 2 (1 mM) or a NO donor (dipropylenetriamine‐NONOate, 200 μM), using whole‐genome DNA microarrays. Genes encoding reactive oxygen and nitrogen species detoxification enzymes had high transcriptional levels under basal conditions and upon exposure to both stresses. On a whole‐genome level, there was significant modulation of gene expression by H 2 O 2 (286 genes regulated) and dipropylenetriamine‐NONOate (1036 genes regulated) with a significant overlap of genes modulated under both conditions (164 genes). A number of transcriptionally regulated genes were in signalling/regulatory and repair/metabolic pathways. However, the majority of genes with altered transcription encode unknown proteins, suggesting as yet unraveled response pathways in E. histolytica . Trophozoites of a non‐pathogenic E. histolytica strain had a significantly muted transcriptional response to H 2 O 2 compared with the pathogenic strain, hinting that differential response to oxidative stress may be one factor that contributes to the pathogenic potential of E. histolytica .