Journal Article

TANGO1 membrane helices create a lipid diffusion barrier at curved membranes

Pincet, Frederic, Malhotra, Vivek, Ernst, Andreas M, Campelo, Felix, Raote, Ishier, Rothman, James E

2020

Overview

We have previously shown TANGO1 organises membranes at the interface of the endoplasmic reticulum (ER) and ERGIC/Golgi (Raote et al., 2018). TANGO1 corrals retrograde membranes at ER exit sites to create an export conduit. Here the retrograde membrane is, in itself, an anterograde carrier. This mode of forward transport necessitates a mechanism to prevent membrane mixing between ER and the retrograde membrane. TANGO1 has an unusual membrane helix organisation, composed of one membrane-spanning helix (TM) and another that penetrates the inner leaflet (IM). We have reconstituted these membrane helices in model membranes and shown that TM and IM together reduce the flow of lipids at a region of defined shape. We have also shown that the helices align TANGO1 around an ER exit site. We suggest this is a mechanism to prevent membrane mixing during TANGO1-mediated transfer of bulky secretory cargos from the ER to the ERGIC/Golgi via a tunnel.

• Publisher: eLife Science Publications, Ltd,eLife Sciences Publications Ltd,eLife Sciences Publication,eLife Sciences Publications, Ltd
• Subject: Aryl Hydrocarbon Receptor Nuclear Translocator - chemistry / Aryl Hydrocarbon Receptor Nuclear Translocator - metabolism / Biosynthesis / Cell Biology / Cellular Biology / collagen / Diffusion / Endoplasmic reticulum / Endoplasmic Reticulum - metabolism / Golgi apparatus / HeLa Cells / Humans / intramembrane / Life Sciences / lipid / Lipid Metabolism / Lipids / Machinery / membrane curvature / Membranes / Microscopy / Proteins / Research Advance / secretion / Structural Biology and Molecular Biophysics / transmembrane