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 bee n observed between the cerebellum and retina form the basis for ongoin g investigations into retinal expression of cerebellar-specific protei ns. We have examined the mouse, rat, rabbit, and human retina for expr ession of a protein that is present in parasagittal Purkinje cell stri ps and that is recognized by the antibody Zebrin-II. This protein has recently been identified as a member of the aldolase C isoenzymes. Wes tern blotting and immunocytochemistry have been used. The monoclonal a ntibody Zebrin-II recognized a prominent 36 kDa protein band on immuno blots of both the cerebellum and the retina of the examined species. I mmunocytochemistry showed that, in the three nonhuman species, cells w ere stained in the ganglion cell layer (GCL). In addition, in the mous e and rabbit, cells in the inner nuclear layer (INL) were also labeled . Except for the visual streak, there were more immunopositive cells i n the rabbit GCL and INL than in corresponding areas of the mouse reti na. In the human, in contrast to the other species, the photoreceptor cell layer was strongly aldolase C immunoreactive. In all species exce pt 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. Fu rthermore, the retinal expression is species specific, and this patter n seems to show a good correlation with the oxygenation level of the i ndividual compartments. The indication that this aldolase C isoenzyme has specific developmental functions in the retina provides additional clues for our understanding of cerebellar organization. (C) 1994 Wiie y-Liss, Inc.