Expression of recoverin mRNA in the human retina: localization by in situ hybridization.

The localization of mRNA encoding recoverin in the human retina was examined by in situ hybridization. The riboprobe utilized in this study was transcribed from a cDNA clone containing the complete coding region of human recoverin. The riboprobe hybridized extensively with the photoreceptor inner segments, and the outer nuclear layer. Specific hybridization was also seen in a subpopulation of cells in the inner nuclear layer, and occasionally in cells of the ganglion cell layer (GCL). Recoverin-like immunoreactivity was observed in all photoreceptors, and in a subpopulation of bipolar cells. Very robust immunolabeling was observed in a small population of cells in the GCL. This study suggests that recoverin, or a recoverin-like protein, is produced by at least three different cell types in the human retina: photoreceptors, bipolars and rare cells in the ganglion cell layer.