Modeling the Novel Gene in Zebra Fish: EXD2 (Exonuclease 3'-5' Domain Containing 2)
EXD2 (Exonuclease 3'-5' Domain Containing 2) is a known gene and reported to be an essential tool in repairing DNA double-strand breaks (DSBs) by homologous recombination through its 3′–5′ exonuclease activity. At this time, there is no report indicating any relation to human disease resulting from alteration in the EXD2 gene. However, several laboratories works illustrated that EXD2 has critical roles in cell function. Zebra fish facilitated the functional study of novel genes as a model for human diseases by utilizing morpholinos as knocking down agents. Disturbing the EXD2 gene showed multiple deformities in the body, which may reflect the critical role in animal tissues and development at the early stages. The expression profile of the exd2 differed in several organs from an adult AB-zebra fish, and also the expression of exd2 increased with an advance in age. Disturbing exd2 caused multiple defects and embryos dead at five-days old. Human RNA suppressed the phenotypes and helped the embryos to grow normally.