Use of the ND evidence code for Gene Ontology (GO) terms
bZIP transcription factor zip-2 mediates an early response to Pseudomonas aeruginosa infection in Caenorhabditis elegans.
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Defines the "infection response gene" (irg) class as genes specifically induced by virulent P. aeruginosa but not by an attenuated gacA mutant; irg-2 is a member of this class.
"We focused on genes that are induced in C. elegans by infection with the bacterial pathogen Pseudomonas aeruginosa, but are not induced by an isogenic attenuated gacA mutant."
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The bZIP transcription factor ZIP-2 is required for inducing irg-1 and several other infection-response genes and is important for defense against P. aeruginosa.
"This screen identified zip-2, a bZIP transcription factor that is required for inducing irg-1, as well as several other genes, and is important for defense against infection by P. aeruginosa."
p38 MAPK regulates expression of immune response genes and contributes to longevity in C. elegans.
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irg-2 (C49G7.5) is among the top P. aeruginosa-induced genes and is induced via a PMK-1 (p38 MAPK)-independent pathway.
"The remaining two genes (C49G7.5 and F53E10.4) must therefore be induced via a PMK-1–independent pathway"
C. elegans detects pathogen-induced translational inhibition to activate immune signaling.
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The zip-2/irg surveillance pathway is activated by pathogen-induced inhibition of host mRNA translation, sensed via endocytosed Exotoxin A, which raises ZIP-2 protein levels.
"P. aeruginosa infection inhibits mRNA translation in the intestine via the endocytosed translation inhibitor Exotoxin A, which leads to an increase in ZIP-2 protein levels."
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The zip-2/irg-1 pathway is also induced by disruption of core host processes including translational inhibition, independent of infection.
"In the absence of infection we find that the zip-2/irg-1 pathway is upregulated following disruption of several core host processes, including inhibition of mRNA translation."
A cellular surveillance and defense system that delays aging phenotypes in C. elegans.
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irg-2 is a bona fide ZIP-2 target whose expression rises strongly with age; the age-dependent increase is largely ZIP-2-dependent.
"the expression of the ZIP-2 targets irg-1 (Figure 2A) and irg-2 (Figure 2B) increased 24.0-fold and 15.5-fold, respectively, from day 1 to day 8 of adulthood"
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The age-dependent increases in irg-1 and irg-2 depend on ZIP-2.
"indicating that the age-dependent increases in irg-1 and irg-2 expression were largely dependent on ZIP-2."
A conserved role for a GATA transcription factor in regulating epithelial innate immune responses.
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Genome-wide study identifying the endodermal GATA factor ELT-2 as a major regulator of the intestinal infection-response transcriptional program that includes irg-2.
"Gene expression and functional RNAi-based analyses identified the tissue-specific GATA transcription factor ELT-2 as a major regulator of an early intestinal protective response to infection with the human bacterial pathogen Pseudomonas aeruginosa."