Figure 1. Physical and mathematical model of a FA.
The FA is the grey-colored parallelogram. Binders are shown as double ellipses, either free or bound in complexes. The bound complexes have been depicted to be larger, of length in the
-direction and their elastic response is represented by the springs. The elastic elements have length
along the
-direction. (Note that
is an arbitrary length and has no effect on the potential; see the section titled “Driving force due to elasticity”.) The dotted arrows are actin stress fibers, which transfer force to the attached complexes. The bundle of actin stress fibers transmits total force
. Also shown are the proximal and distal ends,
, the centroid
, length
and domain boundaries
.