The Drosophila homolog of yeast Aut1, CG6877/Draut1, is a ubiquitously expressed cytosolic protein. Draut1 loss of function was achieved by expression of an inverted repeat transgene inducing RNA interference. The effect is temperature-dependent and resembles an allelic series as described by Fortier, E. and Belote, J.M. (Genesis 26 (2000) 240-244). Draut1 loss of function larvae are unable to induce autophagy and heterophagy in fat body cells before pupariation and die during metamorphosis. To our knowledge, this is the first report of a multicellular animal lacking the function of a gene participating in the protein conjugation systems of autophagy.