Caveolin-1 affects serotonin binding and cell surface levels of human 5-HT7(a) receptors

FEBS Lett. 2007 Oct 30;581(26):5115-21. doi: 10.1016/j.febslet.2007.09.059. Epub 2007 Oct 8.


Studies using HeLa cells expressing 5-HT7 receptors showed that detergent resistant membranous lipid rafts purified by sucrose gradient centrifugation contained 5-HT7 receptors and caveolin-1. Caveolin-1 siRNA-mediated knockdown or serotonin (5-HT) treatment caused significant reductions of maximum [3H]5-HT binding to 5-HT7 receptors and total immunoreactivity of membranous 5-HT7 receptors in intact cells. Co-treatment with 5-HT, caveolin-1 siRNA and methyl-beta-cyclodextrin had no additive effects on reducing maximum binding of [3H]5-HT to 5-HT7 receptors. 5-HT-mediated reduction of [3H]5-HT binding to 5-HT7 receptors was counteracted by genistein, but not by sucrose. Caveolin-1, specifically localized in cholesterol-enriched lipid rafts, appears to regulate constitutive and agonist-stimulated cell surface levels of 5-HT7 receptors via a clathrin-independent mechanism.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Caveolin 1 / analysis
  • Caveolin 1 / genetics
  • Caveolin 1 / metabolism*
  • Cell Membrane / chemistry
  • Cell Membrane / metabolism*
  • HeLa Cells
  • Humans
  • Membrane Microdomains / chemistry
  • Membrane Microdomains / metabolism*
  • RNA, Small Interfering / pharmacology
  • Receptors, Serotonin / analysis
  • Receptors, Serotonin / genetics
  • Receptors, Serotonin / metabolism*
  • Serotonin / metabolism*


  • Caveolin 1
  • RNA, Small Interfering
  • Receptors, Serotonin
  • serotonin 7 receptor
  • Serotonin