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Genetic and dietary regulation of lipid droplet expansion in Caenorhabditis elegans.

ABSTRACT: Dietary fat accumulates in lipid droplets or endolysosomal compartments that undergo selective expansion under normal or pathophysiological conditions. We find that genetic defects in a peroxisomal beta-oxidation pathway cause size expansion in lipid droplets that are distinct from the lysosome-related organelles in Caenorhabditis elegans. Expansion of lipid droplets is accompanied by an increase in triglycerides (TAG) that are resistant to fasting- or TAG lipase-triggered lipolysis. Nevertheless, in mutant animals, a diet poor in vaccenic acid reduced the TAG level and lipid droplet size. Our results implicate peroxisomal dysfunction in pathologic lipid droplet expansion in animals and illustrate how dietary factors modulate the phenotype of such genetic defects.

SUBMITTER: Zhang SO

PROVIDER: S-EPMC2842062 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature

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Genetic and dietary regulation of lipid droplet expansion in Caenorhabditis elegans.

Zhang Shaobing O SO Box Andrew C AC Xu Ningyi N Le Men Johan J Yu Jingyi J Guo Fengli F Trimble Rhonda R Mak Ho Yi HY

Proceedings of the National Academy of Sciences of the United States of America 20100222 10

Dietary fat accumulates in lipid droplets or endolysosomal compartments that undergo selective expansion under normal or pathophysiological conditions. We find that genetic defects in a peroxisomal beta-oxidation pathway cause size expansion in lipid droplets that are distinct from the lysosome-related organelles in Caenorhabditis elegans. Expansion of lipid droplets is accompanied by an increase in triglycerides (TAG) that are resistant to fasting- or TAG lipase-triggered lipolysis. Nevertheles ...[more]

PMID: 20176933

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