Mechanisms of Gating of Mechanosensitive Channels of Large Conductance (MscL)

Xi Chen
Columbia University, USA

The gating pathways of mechanosensitive channels of large conductance (MscL) in E.coli are studied using a molecular dynamics-decorated finite element method. The phenomenological model treats transmembrane helices as elastic rods and the lipid membrane as an elastic sheet of finite thickness. the interactions between various continuum components are derived from atomistic energy calculations. The continuum model is established within the Abaqus FEA product suite (with user interaction). The picture shows the conformational changes and gating mechanisms of MscL when the membrane is under equi-biaxial tension (with t=0 as closed state under zero strain, and t=0 as the fully opened state under a membrane strain of 28%). The rods are various transmembrane and cytoplasmic helices and the lines are loops connecting them. The images generated by the Abaqus FEA product suite were featured as the cover of Biophysical Journal (August 2006).