ZnO nanoparticles exposure alters transcriptomic profile in Hydra

Abstract

The acute toxicity test for 20 nm ZnO and 100 nm ZnO and comparative transctriptomic profile analysis using hydra exposed to 20 nm ZnO and 100 nm ZnO were carried out. As a result, the LC50 for 72 hours was 8.7 mg/L in 20 nm ZnO exposure and 14.9 mg/L in 100 nm ZnO exposure group. For the microarray experiment we exposed hydra to 20 nm ZnO and 100 nm ZnO as the concentration of 1/50 of LC50 for 12 hours and hybridized those RNAs extracted from the exposed groups with that of control group on the hydra cDNA chips including 17,639 genes. As the results, 137 genes expressions were induced and 106 genes were reduced over 10 fold by 20 nm ZnO exposure. Among them the expression of multidrug-Resistance like Protein 1 CG6214-PM gene increased over 100-fold. In 100 nm ZnO exposure, the expressions of 137 genes were induced over 10 fold and 106 genes were reduced over 10 fold. The upregulated more than 2-fold in both 20 nm and 100 nm ZnO exposures were 886 genes and most of them belonged to cellular processes and signaling category and especially they were related to signal transduction mechanisms. The downregulated more than 2-fold in both 20 nm and 100 nm ZnO exposures were 1006 genes and most of them were related to signal transduction mechanisms. The functional clustering of differentially expressed genes by ZnO nanoparticle exposure showed that those nanoparticles tend to affect the transcripre and 14.9 mg/L in 100 nm ZnO exposure group. For the microarray experiment we exposed hydra to 20 nm ZnO and 100 nm ZnO as the concentration of 1/50 of LC50 for 12 hours and hybridized those RNAs extracted from the exposed groups with that of control group on the hydra cDNA chips including 17,639 genes. As the results, 137 genes expressions were induced and 106 genes were reduced over 10 fold by 20 nm ZnO exposure. Among them the expression of multidrug-Resistance like Protein 1 CG6214-PM gene increased over 100-fold. In 100 nm ZnO exposure