Molecular characterization of the zebrafish ff1b gene

Abstract

The nuclear receptor, Ff1b, has been previously established as the master regulator of the organogenesis and the maintenance of interrenal gland in zebrafish. The molecular studies of Ff1b in relation to its putative target gene promoter, cyp11a1, have ascertained its conserved function as the major transcriptional regulator in the steroidogenesis pathway. To create an in vivo system for the functional studies of Ff1b, a transgenic zebrafish model has been generated using a recombined BAC clone spanning 100 kb of ff1b locus with EGFP reporter inserted into Exon 2. The transgenic GFP expression that faithfully recapitulates the endogenous ff1b expression in zebrafish embryos is useful for the real-time monitoring of interrenal development in response to chemical treatment and morpholino injection. Lastly, a combination of truncating specific genomic fragments from the recombined BAC through Red/ET recombination and microinjecting into zebrafish embryos has located a novel interrenal-specific enhancer to IntronIV of ff1b gene.