In the present study, toxicity of multi-wall carbon nanotube (MWCNT) was investigated in Caenohabditis elegans using microarray and mutant analyses. Whole genome microarray was conducted to screen the global changes in C. elegans transcription profiles 4 and 24 h after MWCNT exposure. Interactome analysis was subsequently conducted on differentially expressed genes using Ingenuity Pathways Analysis (IPA) software. After 4 h exposure to MWCNT, 846 genes were differentially expressed in C.elegans, whereas 24 h after exposure, 2247 genes were affected. Interactive gene networks corresponding to Eukaryotic Initiation Factors 4 (EIF4) pathways were highly overexpressed 4 h after MWCNT exposure, whereas NF-kB pathways were downregulated 24 h after exposure. Toxicity of MWCNT was also investigated on 27 potentially stress response C.elegans mutants using survival and reproduction as endpoints. Among the tested mutants, akt-1
(AKT signaling), nsy-1
MAPK signaling) and cep-1
) mutants showed more sensitive response to MWCNT exposure than wildtype did, in terms of reproduction potential. Gene expression analysis, subsequently conducted on selected genes in MAPK, AKT, Apoptosis signaling pathways, revealed that expression of nsy, mpk-2
genes was increased in C.elegans exposed to MWCNT. Overall results suggest that MWCNT possess considerable potential of causing toxicity in C.elegans, and stress signaling pathways seem to be involved in it. Acknowledgement: This work was supported by National Research Foundation of Korea (NRF) grant (2010-0016195).