Original Publication Date
The Biophysical Journal
DOI of Original Publication
Date of Submission
Phosphoinositides like phosphatidylinositol 4,5-bisphosphate (PIP2) are negatively charged lipids that play a pivotal role in membrane trafficking, signal transduction, and protein anchoring. We have designed a force field for the PIP2 headgroup using quantum mechanical methods and characterized its properties inside a lipid bilayer using molecular dynamics simulations. Macroscopic properties such as area/headgroup, density profiles, and lipid order parameters calculated from these simulations agree well with the experimental values. However, microscopically, the PIP2 introduces a local perturbation of the lipid bilayer. The average PIP2 headgroup orientation of 45° relative to the bilayer normal induces a unique, distance-dependent organization of the lipids that surround PIP2. The headgroups of these lipids preferentially orient closer to the bilayer normal. This perturbation creates a PIP2 lipid microdomain with the neighboring lipids. We propose that the PIP2 lipid microdomain enables the PIP2 to function as a membrane-bound anchoring molecule.
From The Biophysical Journal, Lupyan, D., Mezei, M., Logothetis, D.E., et al., A Molecular Dynamics Investigation of Lipid Bilayer Perturbation by PIP2, Vol. 98, Page 240. Copyright © 2010 Biophysical Society. Published by Elsevier Inc. Reprinted with permission.
Is Part Of
VCU Physiology and Biophysics Publications