Takechi, M. and Kawamura, S. (2005). Temporal and spatial changes in the expression pattern of multiple red and green subtype opsin genes during zebrafish development. The Journal of Experimental Biology, 208 (7):1337-1345.

We showed by in situ hybridization the dynamic expression patterns of the opsin subtypes in the zebrafish retina. Expression of red type opsins is initiated with the shorter-wavelength subtype LWS-2, followed by the longer-wavelength subtype LWS-1. In the adult retina, LWS-2 was expressed in the central to dorsal area and LWS-1 in the ventral and peripheral areas. Expression patterns of green type opsins were similar to those of the red type opsins. The expression started with the shortest wavelength subtype RH2-1 followed by the longer wavelength ones, and in the adult retina, the shorter wavelength subtypes (RH2-1 and RH2-2) were expressed in the central to dorsal area and longer wavelength subtypes (RH2-3 and RH2-4) in the ventral and peripheral areas. These results provide a framework for subsequent studies of opsin gene regulation and for probing functional rationale of the developmental changes by using the power of zebrafish genetics.