(B, C) Electron microscopy of p27+/+ (a, c and e) and p27−/− (b, d and f) MEFs treated with (c and d), or without (a and b) AICAR (1 mM), or without glucose (e and f) for 14 h. Magnified images of the boxed areas were shown on the left (a′, b′, c′, d′, e′ and f′) with arrowheads indicating autophagic vacuoles including autolysosomes (black arrowheads). The scale bars represent 10 μm in a-f and 0.5 μm in a′-f′. N, nucleus. Autophagic vacuoles were counted for three randomly selected cells from each electron microscopy section and data represent mean ± s.d. (C). 