Lipolysis-stimulated lipoprotein receptor: a novel membrane protein of tricellular tight junctions

Ann N Y Acad Sci. 2012 Jun;1257:54-8. doi: 10.1111/j.1749-6632.2012.06486.x.

Abstract

Tricellular tight junctions (tTJs) are specialized structural variants of tight junctions that restrict the free diffusion of solutes at the extracellular space of tricellular contacts. Their presence at cell corners, situated in the angles between three adjacent epithelial cells, was identified early by electron microscopy, but despite their potential importance, tTJs have been generally ignored in epithelial cell biology. Tricellulin was the first molecular component of tTJs shown to be involved in their formation and in epithelial barrier function. However, the precise molecular organization and function of tTJs are still largely unknown. Recently, we identified the lipolysis-stimulated lipoprotein receptor (LSR) as a tTJ-associated membrane protein. LSR recruits tricellulin to tTJs, suggesting that the LSR-tricellulin system plays a key role in tTJ formation. In this paper, we summarize the identification and characterization of LSR as a molecular component of tTJs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Epithelial Cells / metabolism*
  • Extracellular Space / metabolism
  • Humans
  • Lipolysis
  • Lipoproteins / metabolism*
  • MARVEL Domain Containing 2 Protein / metabolism*
  • Membrane Proteins / chemistry
  • Membrane Proteins / metabolism*
  • Microscopy, Electron
  • Protein Transport / physiology*
  • Receptors, LDL / metabolism*
  • Tight Junctions / metabolism*

Substances

  • Lipoproteins
  • MARVEL Domain Containing 2 Protein
  • MARVELD2 protein, human
  • Membrane Proteins
  • Receptors, LDL
  • lipolysis-stimulated receptor