A cluster of thin tubular structures mediates transformation of the endoplasmic reticulum to autophagic isolation membrane.

ABSTRACT: Recent findings have suggested that the autophagic isolation membrane (IM) might originate from a domain of the endoplasmic reticulum (ER) called the omegasome. However, the morphological relationships between ER, omegasome, and IM remain unclear. In the present study, we found that hybrid structures composed of a double FYVE domain-containing protein 1 (DFCP1)-positive omegasome and the IM accumulated in Atg3-deficient mouse embryonic fibroblasts (MEFs). Moreover, correlative light and electron microscopy and immunoelectron microscopy revealed that green fluorescent protein (GFP)-tagged DFCP1 was localized on tubular or vesicular elements adjacent to the IM rims. Through detailed morphological analyses, including optimization of a fixation method and electron tomography, we observed a clu

SUBMITTER: Uemura T 

PROVIDER: S-EPMC3993601 | biostudies-literature | 2014 May

REPOSITORIES: biostudies-literature