Vesicle formation within endosomes: An ESCRT marks the spot

Abstract

Vesicle-mediated cargo transport within the endomembrane system requires precise coordination between adaptor molecules, which recognize sorting signals on substrates, and factors that promote changes in membrane architecture. At endosomal compartments, a set of protein complexes collectively known as the ESCRT machinery sequesters transmembrane cargoes that harbor a ubiquitin modification and packages them into vesicles that bud into the endosome lumen. Several models have been postulated to describe this process. However, consensus in the field remains elusive. Here, we discuss recent findings regarding the structure and function of the ESCRT machinery, highlighting specific roles for ESCRT-0 and ESCRT-III in regulating cargo selection and vesicle formation.

Keywords: :

• intralumenal vesicle
• membrane curvature
• membrane scission
• membrane trafficking
• multivesicular endosome
• phosphatidylinositol 3-phosphate
• ubiquitin

Acknowledgments

We thank members of the Audhya lab for critically reading the manuscript. This work was supported by a grant from the NIH (1R01GM088151–01A1) to A.A.