Temporal and spatial expression of RNases from zebrafish (Danio rerio).

We have recently isolated and characterized three zebrafish (Danio rerio) RNases, ZF-RNase-1,-2 and -3, endowed with diverse bioactivities, including microbicidal and angiogenic activities. In the present study we have analyzed their temporal and spatial gene expression profiles. Our results indicate that the three ZF-RNase genes have a differential expression pattern, with ZF-RNase-1 having the most unique and dynamic expression profile. This is characterized by expression in embryonic stages and later on, in larvae, juvenile and adult organisms. In contrast, ZF-RNase-2 and -3 are only expressed either in juvenile or adult organisms. Moreover, analysis of spatial expression of ZF-RNase-1, -2 and -3 detected the three different transcripts in liver, heart, gut and swim bladder tissues. Interestingly, ZF-RNase-1 was the only gene expressed in the brain of embryonic and adult organisms. Collectively, the results suggest that the three ZF-RNases may have potential distinct functional role(s) in zebrafish either during embryonic development and/or later on, in juvenile as well as in adult organisms. Indeed, taking advantage of zebrafish as an excellent viable model to study gene function, this study opens the way to an investigation of the in vivo role(s) of ZF-RNase-1 during embryonic development, as well as, during organogenesis.