Electrical properties of plasma membrane modulate subcellular distribution of K-Ras

GOMEZ G.A.; DANIOTTI J.L.

FEBS JOURNAL

Published by Blackwell Pub. on behalf of the Federation of European Biochemical Societies

Lugar: Londres; Año: 2007 vol. 274 p. 2210 - 2210

1742-464X

p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt; LINE-HEIGHT: 200%; TEXT-ALIGN: justify; tab-stops: 21.6pt 43.2pt">K-Ras is a small G-protein, localized mainly at the inner leaflet of the plasma membrane. The membrane targeting signal of this protein consists of a polybasic C-terminal sequence of six contiguous lysines and a farnesylated cysteine. Results from biophysical studies in model systems suggest that hydrophobic and electrostatic interactions are responsible for the membrane binding properties of K-Ras. To test this hypothesis in a cellular system, we first evaluated in vitro the effect of electrolytes on K-Ras membrane binding properties. Results demonstrated the electrical and reversible nature of K-Ras binding to anionic lipids in membranes. We next investigated membrane binding and subcellular distribution of K-Ras after disruption of the electrical properties of the outer and inner