Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

Lipid droplets (LDs) are the major fat storage organelles in eukaryotic cells, but how their size is regulated is unknown. Using genetic screens in C. elegans for LD morphology defects in intestinal cells, we found that mutations in atlastin, a GTPase required for homotypic fusion of endoplasmic reticulum (ER) membranes, cause not only ER morphology defects, but also a reduction in LD size. Similar results were obtained after depletion of atlastin or expression of a dominant-negative mutant, whereas overexpression of atlastin had the opposite effect. Atlastin depletion in Drosophila fat bodies also reduced LD size and decreased triglycerides in whole animals, sensitizing them to starvation. In mammalian cells, co-overexpression of atlastin-1 and REEP1, a paralog of the ER tubule-shaping protein DP1/REEP5, generates large LDs. The effect of atlastin-1 on LD size correlates with its activity to promote membrane fusion in vitro. Our results indicate that atlastin-mediated fusion of ER membranes is important for LD size regulation.

Original publication

DOI

10.1016/j.celrep.2013.04.015

Type

Journal article

Journal

Cell Rep

Publication Date

30/05/2013

Volume

3

Pages

1465 - 1475

Keywords

Animals, COS Cells, Caenorhabditis elegans, Caenorhabditis elegans Proteins, Chlorocebus aethiops, Cytoplasmic Vesicles, Drosophila, Endoplasmic Reticulum, GTP Phosphohydrolases, GTP-Binding Proteins, Humans, Membrane Proteins, Membrane Transport Proteins, Mutation, RNA Interference, RNA, Small Interfering