We established the transgenic lines of zebrafish carrying green fluorescent
protein (GFP) gene under the 1.1-kb and 3.7-kb upstream regions of the
rod-opsin gene (RH1). In transgenic fishes GFP expression initiated and
proceeded in the same spatiotemporal pattern with rod-opsin gene. The retinal
section from adult transgenic fish showed GFP expression throughout the
rod cell layer. These results indicate that the proximal 1.1-kb region
is sufficient to drive gene expression in all rod photoreceptor cells.
These transgenic fish should facilitate screening of mutants affected specifically
with rod-opsin expression or rod cell development by visualization of rod
cells by GFP.