INVESTIGADORES
SIGAUT Lorena
congresos y reuniones científicas
Título:
Focal adhesion protein zyxin aggregation state in response to mechanical stress using an equibiaxial stretching device
Autor/es:
CATALINA VON BILDERLING; LORENA SIGAUT; LAURA ESTRADA; LÍA PIETRASANTA
Reunión:
Congreso; II Latin American Federation of Biophysical Societies Congreso / xxxVII Congreso of the Brazilian Biophysical Society; 2012
Resumen:
Mechanical forces play an important role in the
organization, growth, maturation, and function of living tissues. Mechanotransduction,
the process by which cells sense and respond to mechanical signals, is mediated
by extracellular matrix, transmembrane integrin receptors, cytoskeletal
structures and associated signaling molecules organized in flat, elongated and
transient structures known as focal adhesions (FAs). In the presence of a
mechanical stimulus, FAs are dynamically assembled and disassembled and this
constant remodeling is presumably governed by the modulation of temporary
interactions between its constituent proteins [Nat. Rev. Mol. Cell. Biol., 7:265-275, 2006]. The
understanding of the biophysical and molecular mechanisms underlying these
events requires the development of techniques to identify the organization and
dynamics of the FAs proteins in response to a mechanical stimulus. These
techniques may have a high spatio-temporal resolution to detect transient and
strongly localized events that occur in a region of the cell.
In this work, we introduce a stretching device
(BMC Cell Biology 10:55-68, 2009) that allows both live fluorescence
imaging and mechanical equibiaxial stretching of the cells cultured on silicone
elastic membranes. Careful characterization of the device described herein
shows its capability of delivering up to 12% of two-dimensional homogeneous
strain to silicone membranes. We were able to study the distribution and
stoichiometry of the FA protein zyxin in response to stretching. We have
expressed in epithelial mammalian living cells (HC11) zyxin protein tagged with
green fluorescent protein (GFP) and obtained, as a function of an applied
force, the stoichiometry of the zyxin aggregates by Number and Brightness
(Biophys. J. 94:2320-2332, 2008) analysis.