Genetic analysis of the toxic effect of Tachyplesin I on the embryonic development of zebrafish

Tachyplesin I (TP-I) is an antimicrobial peptide isolated from the hemocytes of the horseshoe crab, Tachypleus tridentatus. In recent years, a series of biochemical analysis has been performed to gain insight into the mechanism of its strong antimicrobial and anticancer activity. With the development of microarray technology, the genetic analysis of the toxic effect of TP-I on embryo is originally considered in our recent study. Based on our microarray data of the embryonic samples treated with the different doses of TP-I, we perform a series of statistical data analysis to explore the biological process of TP-I on genomic level. In this paper, we employ the hexaMplot to illustrate the continuous variation of the gene expressions with the different dose. The hexaMplot was proved to be an intuitive and effective tool to illustrate the interrelations of genes within the different phenotypes. The strength of gradual alternation in gene expression can be implied in the modified hexaMplot by comparing the microarray data among the different doses of TP-I. The probabilistic model-based Hough transform (HT) is used to classify these co-expressed genes. Three line rays supported with the corresponding 174 genes are detected in our analysis. The feature genes identified on the same line ray of hexaMplot may show the similar expression patterns in varying the doses of TP-I. The functional groups of these genes, such as antigen processing, nuclear chromatin, structural constituent of eye lens, show the coherent biological function with the high significant as detected by Gene Ontology analysis.