Vimentin is involved in regulation of mitochondrial motility and membrane potential by Rac1.

Autor: Matveeva EA; Institute of Protein Research, Russian Academy of Sciences, Department of Cell Biology, Moscow 119988, Russia., Venkova LS; Institute of Protein Research, Russian Academy of Sciences, Department of Cell Biology, Moscow 119988, Russia., Chernoivanenko IS; Institute of Protein Research, Russian Academy of Sciences, Department of Cell Biology, Moscow 119988, Russia., Minin AA; Institute of Protein Research, Russian Academy of Sciences, Department of Cell Biology, Moscow 119988, Russia alexminin@gmail.com.
Jazyk: angličtina
Zdroj: Biology open [Biol Open] 2015 Sep 14; Vol. 4 (10), pp. 1290-7. Date of Electronic Publication: 2015 Sep 14.
DOI: 10.1242/bio.011874
Abstrakt: In this study we show that binding of mitochondria to vimentin intermediate filaments (VIF) is regulated by GTPase Rac1. The activation of Rac1 leads to a redoubling of mitochondrial motility in murine fibroblasts. Using double-mutants Rac1(G12V, F37L) and Rac1(G12V, Y40H) that are capable to activate different effectors of Rac1, we show that mitochondrial movements are regulated through PAK1 kinase. The involvement of PAK1 kinase is also confirmed by the fact that expression of its auto inhibitory domain (PID) blocks the effect of activated Rac1 on mitochondrial motility. The observed effect of Rac1 and PAK1 kinase on mitochondria depends on phosphorylation of the Ser-55 of vimentin. Besides the effect on motility Rac1 activation also decreases the mitochondrial membrane potential (MMP) which is detected by ∼20% drop of the fluorescence intensity of mitochondria stained with the potential sensitive dye TMRM. One of important consequences of the discovered regulation of MMP by Rac1 and PAK1 is a spatial differentiation of mitochondria in polarized fibroblasts: at the front of the cell they are less energized (by ∼25%) than at the rear part.
(© 2015. Published by The Company of Biologists Ltd.)
Databáze: MEDLINE