A) Representative histology images of cerebella from 3-months-old mice stained with anti-calbindin antibody, which specifically labels Purkinje cells (Sequier et al, 1988). Note the presence of an intact Purkinje-cell layer in cerebella of wild-type, Ttll1-/-, Ttll7-/- and Ccp1-/-Ttll1-/- mice, in contrast to the complete absence of these cells in Ccp1-/- and Ccp1-/-Ttll7-/- mice. 