Toxicity Of Beta-cypermethrin To Zebraflsh Embryos

We used zebrafish embryos as a model system. Two-dimensional difference gel electrophoresis(2-D DIGE), MALDI-TOF-MS/MS, microarray and RT-PCR were conducted in seccession. Molecularmechanisms for developmental toxicity of beta-CYP on zebrafish were explored afterwards at the levelof post-transcriptomics, proteomics and bioinformatics. Following works has been done in this paper:Acetone as a solubilizing agent was used to assist in stock solution preparation. The embryos ofzebrafish were exposed to different sub-lethal concentrations of Acetone controlled,0,0.05,0.1,0.2,0.6and1mg/L of beta-CYP solutions for72h. With the help of a microscope we observed themorphological changes and hatchability of zebrafish. Compared with control group, the embryosexposed to beta-CYP showed various morphological deformities, including bent tail/body axes, edemain pericardial sac and cyclopia. The results showed a strong promotion of embryos hatching rate afterexposed to beta-CYP. Also, those embryos displayed an increasing toxicity in a dose-dependent manner.Zebrafish embryos were collected and exposed with0.05mg/L beta-CYP at24hpf for Proteomicsresearch. A total of77proteins were detected as differently expressed in treatment groups compared tocontrols by2D-DIGE. Among the77proteins,55proteins were identified by MALDI-TOF. Thedifferentially expressed proteins were generally classified according to their functions, involvingbinding, catalysis, electron carrier, molecular transducer, structural molecule and translation regulator.The function of these proteins involved in multiple signaling pathways included cell co mMunication,glycolysis, inositol metabolism, a mino acid metabolism, carbon fixation, oxidative phosphorylation andMAPK signaling pathway. The differentially expressed proteins play a vital role in life activities, andalso cause severe effects on zebrafish.Zebrafish embryos at48hpf was collected and exposed to0.05mg/L beta-CYP for transcriptomicsresearch. Differentially expressed genes in embryos of zebrafish treated with beta-CYP were analyzedby microarray method. Microarray analyses revealed the significant difference of409mRNAsexpression with threshold values of>1.5-and>–1.5-fold change between treatment and control samples.Of the409mRNAs,121were significantly up-regulated and288were evidently down-regulated(p<0.05). The expression levels of40mRNAs that include5were significantly up-regulated and35were evidently down-regulated (p<0.05) were significantly by threshold values of>2.0-and <–2.0-foldchange. RT-PCR results showed the consistency of expression in microarray data. The differentiallyexpressed genes were generally classified according to their functions, involving antioxidant, binding,catalytic, electron carrier, enzyme regulator, molecular transducer, structural molecule, transcriptionregulator and transporter. The most regulated genes are tumorigenesis, stress factors, metabolism genesand i mMune factors.The function of these proteins involved multiple signaling pathways includedMAPK signaling pathway, Metabolism of xenobiotics by cytochrome P450, arachidonic acidmetabolism, retinol metabolism, a mino acid metabolism, citrate cycle (TCA cycle) and Wnt signalingpathway. We also observe the expression changes of junD gene at12hpf,24hpf,48hpf,72hpf and96hpf.Our results revealed that junD gene expression decreased after exposure at12hpf,24hpf,72hpf and96hpf, while increased at48hpf. These genes can cause the occurrence of the zebrafish tumor and inhibitthe i mMune function of zebrafish.