ATGL has a key role in lipid droplet/adiposome degradation in mammalian cells.
Lipid droplets (LDs), also called adiposomes, are found in many eukaryotic cells, and are highly upregulated in lipid-storage cells, such as adipocytes. The mechanism by which adiposomes and their component neutral lipids are degraded is an important health issue with the rapidly spreading epidemic of obesity. Recently, a novel triglyceride lipase (adipose triglyceride lipase (ATGL)) that catalyses the initial step in triglyceride hydrolysis in adipocyte LDs was identified. Here, we show that ATGL also functions in non-adipocyte cells, and has an important role in LD degradation in these cells. Overexpression of wild-type ATGL causes a marked decrease in LD size, whereas a catalytically inactive mutant retains the ability to localize to LDs, but is unable to decrease their size. Depletion of ATGL by RNA interference leads to a significant increase in the size of LDs. These results show that ATGL has an important role in LD/adiposome turnover in mammalian cells.
Smirnova
Elena
E
Cell Biology and Metabolism Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA.
Goldberg
Elysa B
EB
Makarova
Kira S
KS
Lin
Lin
L
Brown
William J
WJ
Jackson
Catherine L
CL
D017667:Adipocytes / Q000166:cytology / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D004268:DNA-Binding Proteins / Q000378:metabolism; D005456:Fluorescent Dyes / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D008049:Lipase / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D008055:Lipids / Q000737:chemistry; D008969:Molecular Sequence Data; D009765:Obesity / Q000378:metabolism; D000070796:Perilipin-3; D010802:Phylogeny; D011257:Pregnancy Proteins / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D033921:Vesicular Transport Proteins
D004268:DNA-Binding Proteins; D005456:Fluorescent Dyes; D047908:Intracellular Signaling Peptides and Proteins; D008055:Lipids; C038196:PLIN3 protein, human; D000070796:Perilipin-3; D011257:Pregnancy Proteins; D034741:RNA, Small Interfering; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D033921:Vesicular Transport Proteins; D008049:Lipase; C476342:TGL3 protein, S cerevisiae