Alteration of Golgi Structure in Senescent Cells and Its Regulation by a G Protein γ Subunit

Cell Signal. 2011 May;23(5):785-93. doi: 10.1016/j.cellsig.2011.01.001. Epub 2011 Jan 14.

Abstract

Cellular senescence is a process wherein proliferating cells undergo permanent cell cycle arrest while remaining viable. Senescence results in enhanced secretion of proteins that promote cancer and inflammation. We report here that the structure of the Golgi complex which regulates secretion is altered in senescent cells. In cells where senescence is achieved by replicative exhaustion or in cells wherein senescence has been induced with BrdU treatment dependent stress, the Golgi complex is dispersed. The expression of a G protein γ subunit, γ11, capable of translocation from the plasma membrane to the Golgi complex on receptor activation increases with senescence. Knockdown of γ11 or overexpression of a dominant negative γ3 subunit inhibits Golgi dispersal induced by senescence. Overall these results suggest that in cellular senescence an upregulated G protein gamma subunit mediates alterations in the structure of the Golgi.

Publication types

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

MeSH terms

  • Bromodeoxyuridine / pharmacology
  • Cellular Senescence*
  • GTP-Binding Protein beta Subunits / genetics
  • GTP-Binding Protein beta Subunits / metabolism
  • GTP-Binding Protein gamma Subunits / genetics
  • GTP-Binding Protein gamma Subunits / metabolism*
  • GTP-Binding Protein gamma Subunits / physiology
  • Golgi Apparatus / metabolism
  • Golgi Apparatus / ultrastructure*
  • HeLa Cells
  • Humans
  • Interleukin-8 / metabolism
  • RNA Interference
  • RNA, Small Interfering / metabolism

Substances

  • GTP-Binding Protein beta Subunits
  • GTP-Binding Protein gamma Subunits
  • Interleukin-8
  • RNA, Small Interfering
  • Bromodeoxyuridine