Hemifusomes and Interacting Proteolipid Nanodroplets Mediate Multi-Vesicular Body Formation.

ABSTRACT: The complex, pleiomorphic membrane structure of the vesicular components within the endolysosomal system has been appreciated through decades of classical electron microscopy. However, due to the heavy fixation and staining required in these approaches, in situ visualization of fragile intermediates between early endosomes, late endosomes and ultimately multivesicular bodies (MVBs), remains elusive, raising the likelihood that other structures may have also been overlooked. Here, using in situ cryo-electron tomography in four mammalian cell lines, we discover heterotypic hemifused vesicles that share an extended hemifusion diaphragm, associated with a 42nm proteolipid nanodroplet (PND). We term this previously undescribed vesicular organelle-complex, "hemifusome". Hemifusomes make up appro

SUBMITTER: Tavakoli A 

PROVIDER: S-EPMC11537336 | biostudies-literature | 2024 Oct

REPOSITORIES: biostudies-literature