FIT2 organizes lipid droplet biogenesis with ER tubule-forming proteins and septins

© 2021 Chen et al..

Lipid droplets (LDs) are critical for lipid storage and energy metabolism. LDs form in the endoplasmic reticulum (ER). However, the molecular basis for LD biogenesis remains elusive. Here, we show that fat storage-inducing transmembrane protein 2 (FIT2) interacts with ER tubule-forming proteins Rtn4 and REEP5. The association is mainly transmembrane domain based and stimulated by oleic acid. Depletion of ER tubule-forming proteins decreases the number and size of LDs in cells and Caenorhabditis elegans, mimicking loss of FIT2. Through cytosolic loops, FIT2 binds to cytoskeletal protein septin 7, an interaction that is also required for normal LD biogenesis. Depletion of ER tubule-forming proteins or septins delays nascent LD formation. In addition, FIT2-interacting proteins are up-regulated during adipocyte differentiation, and ER tubule-forming proteins, septin 7, and FIT2 are transiently enriched at LD formation sites. Thus, FIT2-mediated nascent LD biogenesis is facilitated by ER tubule-forming proteins and septins.

Medienart:

E-Artikel

Erscheinungsjahr:

2021

Erschienen:

2021

Enthalten in:

Zur Gesamtaufnahme - volume:220

Enthalten in:

The Journal of cell biology - 220(2021), 5 vom: 03. Mai

Sprache:

Englisch

Beteiligte Personen:

Chen, Fang [VerfasserIn]
Yan, Bing [VerfasserIn]
Ren, Jie [VerfasserIn]
Lyu, Rui [VerfasserIn]
Wu, Yanfang [VerfasserIn]
Guo, Yuting [VerfasserIn]
Li, Dong [VerfasserIn]
Zhang, Hong [VerfasserIn]
Hu, Junjie [VerfasserIn]

Links:

Volltext

Themen:

EC 3.6.1.-
FITM2 protein, human
Journal Article
Membrane Proteins
Nogo Proteins
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
Septins

Anmerkungen:

Date Completed 28.09.2021

Date Revised 05.11.2021

published: Print

Citation Status MEDLINE

doi:

10.1083/jcb.201907183

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM324160151