FEBS Lett 2013 Jun 11;587(13):1988-96. Epub 2013 May 11.
Department of Medical Genetics, University of Cambridge, Cambridge Institute for Medical Research, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0XY, UK.
Autophagy is a highly conserved intracytoplasmic degradation pathway for proteins, oligomers, organelles and pathogens. It initiates with the formation of a cup-shaped double membrane structure called the phagophore. The membrane origin for autophagosomes has been a key question for the field. ATG9 and ATG16L1, or their yeast orthologues, are key proteins that regulate autophagosome biogenesis, and may be associated with distinct membrane sources. Here we review the biology of autophagy with a focus on ATG16L1 and ATG9, and we summarise the current knowledge of their trafficking in relation to autophagic stimuli and autophagosome formation.