Pet10p is a yeast perilipin that stabilizes lipid droplets and promotes their assembly

J Cell Biol. 2017 Oct 2;216(10):3199-3217. doi: 10.1083/jcb.201610013. Epub 2017 Aug 11.

Abstract

Pet10p is a yeast lipid droplet protein of unknown function. We show that it binds specifically to and is stabilized by droplets containing triacylglycerol (TG). Droplets isolated from cells with a PET10 deletion strongly aggregate, appear fragile, and fuse in vivo when cells are cultured in oleic acid. Pet10p binds early to nascent droplets, and their rate of appearance is decreased in pet10Δ Moreover, Pet10p functionally interacts with the endoplasmic reticulum droplet assembly factors seipin and Fit2 to maintain proper droplet morphology. The activity of Dga1p, a diacylglycerol acyltransferase, and TG accumulation were both 30-35% lower in the absence of Pet10p. Pet10p contains a PAT domain, a defining property of perilipins, which was not previously known to exist in yeast. We propose that the core functions of Pet10p and other perilipins extend beyond protection from lipases and include the preservation of droplet integrity as well as collaboration with seipin and Fit2 in droplet assembly and maintenance.

MeSH terms

  • Cation Transport Proteins / genetics
  • Cation Transport Proteins / metabolism*
  • GTP-Binding Protein gamma Subunits / genetics
  • GTP-Binding Protein gamma Subunits / metabolism*
  • Glycoproteins / genetics
  • Glycoproteins / metabolism*
  • Lipid Droplets / metabolism*
  • Perilipin-1 / genetics
  • Perilipin-1 / metabolism*
  • Protein Domains
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*

Substances

  • Cation Transport Proteins
  • FIT2 protein, S cerevisiae
  • GTP-Binding Protein gamma Subunits
  • Glycoproteins
  • Perilipin-1
  • Saccharomyces cerevisiae Proteins
  • seipin protein, S cerevisiae