(c) Labelling intensity of PtdIns(3) P in wild-type yeast cultured in S(-NC) for 4 h (average±s.e.m.). PtdIns(3) P was found in both leaflets of the autophagosome and autophagic body membrane, and the labelling was much stronger in the EF than in the PF. In the vacuolar membrane, significant labelling was found in the EF, albeit at much lower levels than in the PF. The experiment was repeated three times, and the number of colloidal gold particles per μm2 was measured in more than ten randomly selected images. 