c, Loss of Purkinje cells in Atg5flox/flox; nestin-Cre mice. Purkinje cells were counted in comparable areas for each mouse, and three fields were counted in each area for each mouse. Data are normalized against values from control mice (Atg5flox/+; nestin-Cre). Values represent mean ± s.d. of three mice. Asterisk, P 0.01 (t-test). 