Developmental Toxicology - Re - Lated Studies with Zebrafish Embryos

lt is widely believed that embryos and infants during devetopment are highly sensitiye to chemicals that cause serious damage to growth. However, knowledge on the mechanisms of developmenta1 toxicity is scarce. One reason for this is limited convenient model system other than organ cultures using rodents to study the various aspects of developmentat toxicology. Cuttured cells are not always adequate for this purpose, since events in morphogenesis are processed through interactions with other tissues. We focused on zebrafish embryo (Danio rerio), one of the most important organisms in deyelopmental biology. Saturation mutagenesis, applied to drosophila and nematode to define the functions of genes, has been carried out in zebrafish but almost no other vertebrate, and seyeral thousand lines are available due to the rapid growth and transparent body of this embryo. Enhanced databases for the geneme and ESTs are ayailable at websites with abundant genetic and biologica) background. By targeted gene knock-down with morpholinomodified antisense oligonucleotieds Received April 3, 2003; revised and accepted May IS, 2003. mechanism of congenital anomaly, which arises from genetic mutation.