Format

Send to

Choose Destination
J Cell Sci. 2017 Jul 15;130(14):2277-2291. doi: 10.1242/jcs.192781. Epub 2017 Jun 2.

Low-intensity pulsed ultrasound promotes cell motility through vinculin-controlled Rac1 GTPase activity.

Author information

1
Wellcome Trust Centre for Cell-Matrix Research, University of Manchester, Manchester M13 9PT, USA.
2
Bioventus Cooperatief, Taurusavenue 31, 2132 LS Hoofddorp, The Netherlands.
3
Wellcome Trust Centre for Cell-Matrix Research, University of Manchester, Manchester M13 9PT, USA christoph.ballestrem@manchester.ac.uk.

Abstract

Low-intensity pulsed ultrasound (LIPUS) is a therapy used clinically to promote healing. Using live-cell imaging we show that LIPUS stimulation, acting through integrin-mediated cell-matrix adhesions, rapidly induces Rac1 activation associated with dramatic actin cytoskeleton rearrangements. Our study demonstrates that the mechanosensitive focal adhesion (FA) protein vinculin, and both focal adhesion kinase (FAK, also known as PTK2) and Rab5 (both the Rab5a and Rab5b isoforms) have key roles in regulating these effects. Inhibiting the link of vinculin to the actin-cytoskeleton abolished LIPUS sensing. We show that this vinculin-mediated link was not only critical for Rac1 induction and actin rearrangements, but was also important for the induction of a Rab5-dependent increase in the number of early endosomes. Expression of dominant-negative Rab5, or inhibition of endocytosis with dynasore, also blocked LIPUS-induced Rac1 signalling events. Taken together, our data show that LIPUS is sensed by cell matrix adhesions through vinculin, which in turn modulates a Rab5-Rac1 pathway to control ultrasound-mediated endocytosis and cell motility. Finally, we demonstrate that a similar FAK-Rab5-Rac1 pathway acts to control cell spreading upon fibronectin.

KEYWORDS:

Endocytosis; LIPUS; Migration; Rac1; Vinculin

PMID:
28576970
PMCID:
PMC5536914
DOI:
10.1242/jcs.192781
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center