Specific RNAi mediated gene knockdown in zebrafish cell lines.

Here we demonstrate highly efficient RNA interference in ZFL, SJD and ZF4 cell lines derived from adult and embryonic zebrafish Danio rerio. Microinjection of siRNAs resulted in silencing in almost 100% of cells while transfection using cationic liposomes led to silencing in 30%. Use of siRNAs against zebrafish lamin A, lamin B2 and the motor protein Eg5, led to knockdown of the target genes with the specific phenotypes expected from prior studies in mammalian cells. In contrast injection of lamin A, GL2 and eGFP siRNAs into zebrafish embryos resulted in morphological defects, abnormal development and early death of most embryos. The results indicate unspecific responses to siRNAs in the embryo but a fully developed and active RNAi machinery in cell lines.