Densin-180: revised membrane topology, domain structure and phosphorylation status

J Neurochem. 2009 Apr;109(2):297-302. doi: 10.1111/j.1471-4159.2009.05951.x. Epub 2009 Feb 2.

Abstract

Densin-180 is a core component of post-synaptic densities, the highly complex molecular assemblies that mediate signaling between neuronal cells. It is a multi-domain scaffold protein characterized by multiple leucine-rich repeat domains plus a single Psd95/Discs large/Zona occludens-1 domain. In its original topology model a single transmembrane segment was proposed with an extracellular N-terminus and an intracellular C-terminus. However, recently discovered in vivo phosphorylation sites are incompatible with this topology. Here, we discuss an all-intracellular and membrane-associated localization of Densin-180 that is consistent with and supported by all the latest experimental data. This revised topology which now includes also a phosphorylation-rich area will have deciding influence on future research involving Densin-180 and its signaling.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Cell Membrane / chemistry
  • Cell Membrane / metabolism
  • Humans
  • Intracellular Membranes / chemistry*
  • Intracellular Membranes / metabolism*
  • Phosphorylation
  • Protein Structure, Tertiary / physiology
  • Sialoglycoproteins / chemistry*
  • Sialoglycoproteins / metabolism*

Substances

  • LRRC7 protein, human
  • Sialoglycoproteins