Purchase this article with an account.
Tadao Maeda, Janis Lem, Krzysztof Palczewski, Françoise Haeseleer; A Critical Role of CaBP4 in the Cone Synapse. Invest. Ophthalmol. Vis. Sci. 2005;46(11):4320-4327. doi: https://doi.org/10.1167/iovs.05-0478.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
purpose. CaBP4, a photoreceptor-specific protein of the rods and cones, is essential for the development and maintenance of the mouse photoreceptor synapse. In this study, double CaBP4/rod α-transducin knockout (Cabp4 –/– Gnat1 –/–) mice lacking the rod-mediated component of electrophysiologic responses were generated and analyzed to investigate the role of CaBP4 in cones.
methods. The retinal morphology and physiologic function of 2-month-old Cabp4 –/– Gnat1 –/– mice were analyzed using immunocytochemistry, electron microscopy, and single-flash and flicker electroretinography (ERG).
results. The thickness of the outer plexiform layer and the number of photoreceptor terminals in Cabp4 –/– Gnat1 –/– mice were reduced to levels similar to those of Cabp4 –/– mice. Single-flash and flicker ERG showed that the amplitude and sensitivity of the b-wave in the Cabp4 –/– Gnat1 –/– mice were severely attenuated compared with those in wild-type and Gnat1 –/– mice.
conclusions. Results indicate that the cone synaptic function in Cabp4 –/– Gnat1 –/– mice was severely disrupted, whereas the morphologic defects observed in Cabp4 –/– Gnat1 –/– mice were similar to those of single Cabp4 –/– knockout mice. This and a previous study reveal that CaBP4 is critical for signal transmission from rods and cones to second-order neurons.
This PDF is available to Subscribers Only