A mechanism of raft formation on both plasma membrane layers

¹ Biophysics Group, Department of Physics, Faculty of Science, Mahidol University, Bangkok 10400, Thailand
² Institute for Innovative Learning, Mahidol University, Nakhon Pathom 73170, Thailand
³ ThEP Center, CHE, 328 Si Ayutthaya Road, Bangkok 10400, Thailand
⁴ Department of Chemistry, Faculty of Science, Mahidol University, Bangkok 10400, Thailand

^a e-mail: kans.mu@gmail.com
^b e-mail: narinnuttavut@gmail.com

Received: 24 April 2013
Revised: 22 August 2013
Accepted: 23 August 2013
Published online: 8 October 2013

Abstract

A double-layered membrane model is proposed to explain raft formation and induction on extracellular (outer) and cytoplasmic (inner) leaflets of plasma membranes in a situation where only the outer layer has a tendency to phase-separate. In the model, lipid exchange with the surrounding medium is allowed on both layers, but lipid exchange between layers is not allowed. Simulations display domain stabilization on both layers. The effect of the lipid recycling frequencies on stationary domain sizes is also investigated. It is found that stationary domain sizes decrease when lipid recycling frequencies are stronger. Linear stability analysis is used to verify the results.