Sensing of Heavy Metals Using Caenorhabditis elegans DNA Microarray

Previously we reported that the possibility of sensing of chemical substances using gene expression patterns analyzed by DNA microarray using Caenorhabditis elegans (C. elegans) as a sensor (Matsuno et al., 2002, 2006). In this study, we evaluated sensitivity and selectivity of above system using a customized DNA microarray for heavy metal responded genes. The results showed that this system showed high sensitivity and selectivity for heavy metals (cadmium chloride, mercury chloride and arsenate). The threshold value for heavy metals is shown to be less than 1 nM. The accumulation of gene expression patterns and responded gene information by this assay system enable us to provide not only the quantities and/or qualities of known chemicals but also those of unknown chemicals in environment samples. It is possible that this system can evaluate total biological and physiological effect level in pollution, since gene expressions reflect composite effects of sources in pollution.