FAT/CD36-mediated long-chain fatty acid uptake in adipocytes requires plasma membrane rafts

Mol Biol Cell. 2005 Jan;16(1):24-31. doi: 10.1091/mbc.e04-07-0616. Epub 2004 Oct 20.

Abstract

We previously reported that lipid rafts are involved in long-chain fatty acid (LCFA) uptake in 3T3-L1 adipocytes. The present data show that LCFA uptake does not depend on caveolae endocytosis because expression of a dominant negative mutant of dynamin had no effect on uptake of [3H]oleic acid, whereas it effectively prevented endocytosis of cholera toxin. Isolation of detergent-resistant membranes (DRMs) from 3T3-L1 cell homogenates revealed that FAT/CD36 was expressed in both DRMs and detergent-soluble membranes (DSMs), whereas FATP1 and FATP4 were present only in DSMs but not DRMs. Disruption of lipid rafts by cyclodextrin and specific inhibition of FAT/CD36 by sulfo-N-succinimidyl oleate (SSO) significantly decreased uptake of [3H]oleic acid, but simultaneous treatment had no additional or synergistic effects, suggesting that both treatments target the same mechanism. Indeed, subcellular fractionation demonstrated that plasma membrane fatty acid translocase (FAT/CD36) is exclusively located in lipid rafts, whereas intracellular FAT/CD36 cofractionated with DSMs. Binding assays confirmed that [3H]SSO predominantly binds to FAT/CD36 within plasma membrane DRMs. In conclusion, our data strongly suggest that FAT/CD36 mediates raft-dependent LCFA uptake. Plasma membrane lipid rafts might control LCFA uptake by regulating surface availability of FAT/CD36.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3T3-L1 Cells
  • Adipocytes / metabolism*
  • Animals
  • Blotting, Western
  • CD36 Antigens / metabolism
  • CD36 Antigens / physiology*
  • Caveolae / metabolism
  • Cell Membrane / metabolism
  • Cells, Cultured
  • Cholera Toxin / metabolism
  • Cholera Toxin / pharmacology
  • Detergents / pharmacology
  • Dynamin II / genetics
  • Endocytosis
  • Fatty Acid Transport Proteins
  • Fatty Acids / metabolism
  • Genes, Dominant
  • Humans
  • Lipids / chemistry
  • Membrane Microdomains / metabolism*
  • Membrane Transport Proteins / metabolism
  • Mice
  • Microscopy, Fluorescence
  • Mutation
  • Oleic Acid / metabolism
  • Oleic Acids / pharmacology
  • Protein Structure, Tertiary
  • Succinimides / pharmacology
  • Time Factors

Substances

  • CD36 Antigens
  • Detergents
  • Fatty Acid Transport Proteins
  • Fatty Acids
  • Lipids
  • Membrane Transport Proteins
  • Oleic Acids
  • SLC27A1 protein, human
  • SLC27A4 protein, human
  • Slc27a1 protein, mouse
  • Slc27a4 protein, mouse
  • Succinimides
  • sulfo-N-succinimidyl oleate
  • Oleic Acid
  • Cholera Toxin
  • Dynamin II