학술논문

TANGO1 membrane helices create a lipid diffusion barrier at curved membranes
Document Type
Academic Journal
Source
eLife. May 26, 2020, Vol. 9
Subject
Lipids
Biological sciences
International economic relations
Language
English
ISSN
2050-084X
Abstract
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.
Byline: Ishier Raote, Andreas M Ernst, Felix Campelo, James E Rothman, Frederic Pincet, Vivek Malhotra Introduction Intracellular membrane trafficking is key for the homeostatic regulation of compositional gradients of proteins [...]