Purchase this article with an account.
A. J. Moldstad, J. M. Fadool; Photoreceptor Development and Visual Response in the Bluefin Killifish, Lucania Goodei. Invest. Ophthalmol. Vis. Sci. 2008;49(13):1258. doi: https://doi.org/.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
The bluefin killifish, Lucania goodei, inhabits a variety of photic environments, including clear springs and turbid swamps. Our previous work has shown that opsin mRNA expression varies across these two spectral environments and this neural plasticity can be replicated in the laboratory (Fuller et al 2004, Fuller et al 2005). The goal of this study is to characterize the photoreceptor cell development and onset of vision in the bluefin killifish to better understand the mechanisms of this neuronal plasticity.
Photoreceptor cell differentiation was characterized on histological sections of embryos and larvae ranging in age from 4 to 12 days post-fertilization (dpf). Sections were immunolabeled with markers for rods (zpr-3) and cones (zpr-1) and counter stained with DAPI. Whole mount in situ hybridization using digoxigenin-labeled riboprobes for green, blue, violet, and UV cone opsins and rhodopsin was performed at 10dpf. The optokinetic response was measured in larvae 8-14 dpf. Larvae were immobilized in methylcellulose and placed on a stage in the center of a rotating drum illuminated by white light.
Immunolabeling of histological sections for rod or cone specific antigens demonstrated that cones could first be detected in the central retina at 5dpf, and markers for rods and cones labeled the central retina at 6dpf. During the next several days, the labeling pattern for both rods and cones spread from the central to the peripheral retina. In situ hybridization for the cone and rod opsins demonstrated that all could be detected by 10dpf. The optokinetic response elicited by rotating vertical stripes was defined as either a pursuit alone, or a pursuit with a saccade. At 8dpf, 8% of fish responded with pursuit alone. At 9dpf, 64% of fish responded, but only 37% presented both a pursuit and a saccade. Response increased steadily until 13dpf, at which stage 98% of fish responded with both a pursuit and a saccade.
These data provide a time-course of photoreceptor cell development in the bluefin killifish. The onset of the optokinetic response corresponds to the onset of photoreceptor cell development and opsin expression. These data form the basis for determining the underlying cellular mechanism contributing to the environmentally induced plasticity in opsin expression.
This PDF is available to Subscribers Only