posted on 2023-12-28, 13:05authored byPeter Pajtinka, Robert Vácha
Curvature sensing
is an essential ability of biomolecules
to preferentially
localize to membrane regions of a specific curvature. It has been
shown that amphipathic helices (AHs), helical peptides with both hydrophilic
and hydrophobic regions, could sense a positive membrane curvature.
The origin of this AH sensing has been attributed to their ability
to exploit lipid-packing defects that are enhanced in regions of positive
curvature. In this study, we revisit an alternative framework where
AHs act as sensors of local internal stress within the membrane, suggesting
the possibility of an AH sensing a negative membrane curvature. Using
molecular dynamics simulations, we gradually tuned the hydrophobicity
of AHs, thereby adjusting their insertion depth so that the curvature
preference of AHs is switched from positive to negative. This study
suggests that highly hydrophobic AHs could preferentially localize
proteins to regions of a negative membrane curvature.