Distribution of Purkinje cell‐specific Zebrin‐II/aldolase C immunoreactivity in the mouse, rat, rabbit, and human retina

The developmental, genetic, and biochemical similarities that have been observed between the cerebellum and retina form the basis for ongoing investigations into retinal expression of cerebellar‐specific proteins. We have examined the mouse, rat, rabbit, and human retina for expression of a protein that is present in parasagittal Purkinje cell strips and that is recognized by the antibody Zebrin‐II. This protein has recently been identified as a member of the aldolase C isoenzymes. Western blotting and immunocytochemistry have been used. The monoclonal antibody Zebrin‐II recognized a prominent 36 kDa protein band on immunoblots of both the cerebellum and the retina of the examined species. Immunocytochemistry showed that, in the three nonhuman species, cells were stained in the ganglion cell layer (GCL). In addition, in the mouse and rabbit, cells in the inner nuclear layer (INL) were also labeled. Except for the visual streak, there were more immunopositive cells in the rabbit GCL and INL than in corresponding areas of the mouse retina. In the human, in contrast to the other species, the photoreceptor cell layer was strongly aldolase C immunoreactive. In the h all species except for the rat, the photoreceptor inner segments also displayed a weak labeling. The results show that this aldolase C isoenzyme is another protein that is selectively expressed by the cerebellum: and retina. Furthermore, the retinal expression is species specific, and this pattern seems to show a good correlation with the oxygenation level of the individual compartments. The indication that this aldolase C isoenzyme has specific developmental functions in the retina provides additional clues for our understanding of cerebellar organization. © 1994 Wiley‐Liss, Inc.