Sensing Membrane Stresses by Protein Insertions
Figure 3
Stress sensing by hydrophobic insertions for laterally uncoupled monolayers.
The elastic binding energy of insertion was computed using the elastic model of a lipid bilayer for the insertion length of 2 nm, the insertion cross-sectional radius of 0.5 nm and the insertion embedding depth of 0.8 nm, as it has been estimated based on structural data for typical amphipathic helices. The monolayer thickness is taken to be 2 nm. The membrane stress was generated in five ways, as presented in Fig. 4 below. (A) The elastic binding energy
as a function of the void energy
, all points laying approximately on a straight line of slope one (black line). (B) The relative binding constant
as a function of the void energy
. The black line shows the expected exponential profile. (C) The elastic binding energy
(left) and the relative binding constant
(right) as functions of the void energy
for two different physiologically relevant cross-sectional radii (
in blue, and
in black) and the embedding depth
. (D) The elastic binding energy
(left) and the relative binding constant
(right) as functions of the void energy
for the insertion cross-sectional radius
and different biologically feasible values of the embedding depth (
in blue,
in black, and
in red).