Novel functions of lipid-binding protein 5 in Caenorhabditis elegans fat metabolism

J Biol Chem. 2011 Aug 12;286(32):28111-8. doi: 10.1074/jbc.M111.227165. Epub 2011 Jun 22.


The lipid-binding protein (LBP) family is conserved from Caenorhabditis elegans to mammals and essential for fatty acid homeostasis. RNAi-mediated knockdown of nine C. elegans lbp family members revealed that lbp-5 regulates fat accumulation. C. elegans LBP-5 bound directly to various fatty acids with varying affinities. lbp-5 expression in nhr-49(nr2041) worms was much lower than in N2 worms. Nhr-49 transcriptional activity also decreased with lbp-5 deletion, suggesting that they may work together as functional partners in fat metabolism. In support of this notion, LBP-5 translocated into nuclei, where it appeared to influence C. elegans NHR-49 target genes involved in energy metabolism. Interestingly, LBP-5 is required for stearic acid-induced transcription of NHR-49 target genes. Thus, this knowledge could help identify therapeutic targets to treat obesity and diseases associated with nematode-host interactions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Active Transport, Cell Nucleus / physiology
  • Animals
  • Caenorhabditis elegans / genetics
  • Caenorhabditis elegans / metabolism*
  • Caenorhabditis elegans Proteins / genetics
  • Caenorhabditis elegans Proteins / metabolism*
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Cell Nucleus / genetics
  • Cell Nucleus / metabolism*
  • Energy Metabolism / physiology
  • Fatty Acid-Binding Proteins / genetics
  • Fatty Acid-Binding Proteins / metabolism*
  • Lipid Metabolism / physiology*
  • Protein Binding
  • Receptors, Cytoplasmic and Nuclear / genetics
  • Receptors, Cytoplasmic and Nuclear / metabolism
  • Stearic Acids / metabolism*
  • Transcription, Genetic / physiology*


  • Caenorhabditis elegans Proteins
  • Carrier Proteins
  • Fatty Acid-Binding Proteins
  • NHR-49 protein, C elegans
  • Receptors, Cytoplasmic and Nuclear
  • Stearic Acids
  • lipid-binding protein 5, C elegans
  • stearic acid