Genome-wide screening identifies new genes required for stress-induced phase 2 detoxification gene expression in animals

Table 1 Activators of stress-induced gcs-1p::gfp expression and their effects on stress-induced phase 2 gene expression, stress resistance, PMK-1 and SKN-1

Functional classification of gene targeted by RNAi			Intestinalgst-4p::gfpexpression		mRNA (Figure2B)		Arsenite resistance	PMK-1 activation	Nuclear levels of SKN-1^S393A::GFP
Functional classification of gene targeted by RNAi			WT (N2) (Additional file1: Table S3)	prdx-2(Additional file2: Figure S3)	gcs-1	gst-7	(Figure2C)	(Figure4)	(Figure6A)
Gene expression	Human orthologue	Proposed function
C17G10.1	OGFOD1	Regulates translation	-	-	↓	-	-	↓	-
C35C5.1 sdc-2	GOLGA6L5	Sex determination/dosage compensation	↓	ND	ND	ND	↓***	↓	-
F47A4.2 dpy-22	MED12	Mediator subunit	-	-	↓*	↓	-	↓	-
C16A3.8 thoc-2	THOC2	Transcriptional elongation	-	↓***	↓***	↓*	↓**	↓	↓***
K04G7.11	SYF2	Pre-mRNA-splicing factor	-	↓**	↓	↓	↓	↓	↓***
Protein homeostasis
Y102A5A.1 cand-1	CAND1	Cullin-associated NEDD8-dissociated	-	↓***	↓*	-	↓*	↓	-
B0025.2 csn-2	CSN2	Cop9 signalosome subunit	↓	↓***	↓	↓***	↓*	-	↓***
T05H10.5 ufd-2	UBE4B	E4 ubiquitin conjugating enzyme	↓	↓***	↓	↓*	↓	-	↓***
Signal transduction
F13B10.1 tir-1	SARM1	Pathogen responses	-	↓***	↓	↓*	↓***	↓***	-
T28H11.2 srm-1	-	Serpentine receptor	-	-	↓**	-	↓	↓	-
ZK792.3 inx-9	-	Innexin	-	-	ND	ND	ND	ND	-
Growth/metabolism
C06A8.1 mthf-1	MTHFR	Methylenetetrahydrofolate reductase	-	↓***	↓**	↓*	↓	↓	-
C34F11.3	AMPD2	AMP deaminase 2	-	↓***	ND	ND	ND	ND	-
Structural
F46E10.11 hpo-26	-	Hypersensitive to pore-forming toxin	-	↓***	ND	ND	↓	↓	↓***
Transport/trafficking
R11A5.1 apb-3	AP3B1/2	Adaptin	-	-	↓**	↓***	-	↓	↓***
Unknown function
F22F7.4	-		-	-	↓*	↓*	-	-	-

Sixteen RNAi that prevented any detectable intestinal gcs-1p::gfp expression in prdx-2 mutant animals and in more than 50% of wild-type animals treated with 1 mM arsenite for 90 min (N2 gcs-1p::gfp) on each of three occasions on which they were screened, following quantitative analysis, but which did not reduce intestinal expression of a non-phase 2 reporter gene, F09E5.3::gfp (Additional file 1: Table S3). These genes were placed into categories based on gene ontology [15]. Where RNAi affected gst-4p::gfp expression in wild-type (Additional file 1: Table S3) or prdx-2 mutant animals (Additional file 2: Figure S3) the effect is indicated by an arrow. Where RNAi produced a greater than 10% change in gcs-1 or gst-7 mRNA levels in arsenite-treated animals (Figure 2B), arsenite resistance (Figure 2A,C), PMK-1 phosphorylation in arsenite-treated animals (Figure 4) or levels of SKN-1^S393A::GFP in intestinal nuclei (Figure 6A) this is indicated. Statistically significant differences from control animals are indicated (*P < 0.05; **P < 0.01; ***P < 0.001). ND, not determined; RNAi, RNA interference; WT, wild type.

ISSN: 1741-7007