Two-piconewton slip bond between fibronectin and the cytoskeleton depends on talin.
Nature. 2003-07-01; 424(6946): 334-337
Lire sur PubMed
1. Nature. 2003 Jul 17;424(6946):334-7.
Two-piconewton slip bond between fibronectin and the cytoskeleton depends on
Jiang G(1), Giannone G, Critchley DR, Fukumoto E, Sheetz MP.
(1)Department of Biological Sciences, Columbia University, 1212 Amsterdam Avenue,
New York, New York 11027, USA.
Mechanical forces on matrix-integrin-cytoskeleton linkages are crucial for cell
viability, morphology and organ function. The production of force depends on the
molecular connections from extracellular-matrix-integrin complexes to the
cytoskeleton. The minimal matrix complex causing integrin-cytoskeleton
connections is a trimer of fibronectin’s integrin-binding domain FNIII7-10 (ref.
4). Here we report a specific, molecular slip bond that was broken repeatedly by
a force of 2 pN at the cellular loading rate of 60 nm x s(-1); this occurred with
single trimer beads but not with monomer. Talin1, which binds to both integrins
and actin filaments in vitro, is required for the 2-pN slip bond and rapid
cytoskeleton binding. Further, inhibition of fibronectin binding to alpha(v)beta3
and deletion of beta3 markedly decreases the 2-pN force peak. We suggest that
talin1 initially forms a molecular slip bond between closely packed
fibronectin-integrin complexes and the actin cytoskeleton, which can apply a low
level of force to fibronectin until many bonds form or a signal is received to
activate a force response.
PMID: 12867986 [Indexed for MEDLINE]