Expression pattern of integrin beta 1 subunit in Purkinje cells of rat and cerebellar mutant mice

We found that integrin beta 1 subunit (INT beta 1)-immunoreactive Purkinje cells first appeared caudally at postnatal day (PD) 6 of rat and most Purkinje cells gradually became positive by PD 12. The expression of INT beta 1 was then suppressed in some of these cells, so that the positive Purkinje cells in the adult were organized into parasagittal bands interposed by negative cells throughout the vermis and hemispheres. When Purkinje cells were deprived of their climbing fiber innervation by inferior cerebellar pedunculotomy or by transplantation of cerebellar anlagen into the anterior eye chamber, the subsequent patterning of INT beta 1-positive Purkinje cells was not changed. In both reeler and weaver mice, the INT beta 1-positive parasagittal bands were observed, however, the Purkinje cells in the staggerer mice did not express INT beta 1 at any stage. These data suggest that the expression of INT beta 1 in Purkinje cells is genetically programmed in the developing cerebellum, and that the afferent synaptic inputs by climbing and parallel fibers are not prerequisites for INT beta 1 expression in Purkinje cells. Therefore, the unique distribution patterns of INT beta 1-positive Purkinje cells provides a new marker for postnatal development of rodent cerebella. (C) 1996 Wiley-Liss, Inc.