Transposable elements drive the evolution of metazoan zinc finger genes

Cys2-His2 Zinc finger genes (ZNFs) form the largest family of transcription factors in metazoans. Zebrafish posess a subfamily characterized by the presence of a domain dubbed Fish N-terminal Zinc finger associated (FiNZ). FiNZ-ZNFs are expressed at the onset of zygotic genome activation in zebrafishh, and blocking FiNZ-ZNF translation using morpholinos during early zebrafish embryogenesis results in a broad de-repression of young, transcriptionally active TEs. Overall design: We designed a single translation-blocking morpholino targeting the translation start site of 400+ FiNZ-ZNF genes on zebrafish chromosome 4. Fertilized, single-celled zygotes were injected with either this morpholino or a scrambled 25N control, and embryos were collected 6h later at shield stage. Injections were repeated in triplicate. Embryos were sent for paired end RNA sequencing, and analysed using DESeq2.