TY - JOUR TI - The ER–Golgi intermediate compartment is a key membrane source for the LC3 lipidation step of autophagosome biogenesis AU - Ge, Liang AU - Melville, David AU - Zhang, Min AU - Schekman, Randy A2 - Levine, Beth VL - 2 PY - 2013 DA - 2013/08/06 SP - e00947 C1 - eLife 2013;2:e00947 DO - 10.7554/eLife.00947 UR - https://doi.org/10.7554/eLife.00947 AB - Autophagy is a catabolic process for bulk degradation of cytosolic materials mediated by double-membraned autophagosomes. The membrane determinant to initiate the formation of autophagosomes remains elusive. Here, we establish a cell-free assay based on LC3 lipidation to define the organelle membrane supporting early autophagosome formation. In vitro LC3 lipidation requires energy and is subject to regulation by the pathways modulating autophagy in vivo. We developed a systematic membrane isolation scheme to identify the endoplasmic reticulum–Golgi intermediate compartment (ERGIC) as a primary membrane source both necessary and sufficient to trigger LC3 lipidation in vitro. Functional studies demonstrate that the ERGIC is required for autophagosome biogenesis in vivo. Moreover, we find that the ERGIC acts by recruiting the early autophagosome marker ATG14, a critical step for the generation of preautophagosomal membranes. KW - autophagy KW - ER–Golgi intermediate compartment KW - LC3 lipidation KW - autophagosome JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -