Tserkovnyak Yaroslav, Nelson David R
Lyman Laboratory of Physics, Harvard University, Cambridge, MA 02138, USA.
Proc Natl Acad Sci U S A. 2006 Oct 10;103(41):15002-7. doi: 10.1073/pnas.0606992103. Epub 2006 Sep 28.
We study protein diffusion in multicomponent lipid membranes close to a rigid substrate separated by a layer of viscous fluid. The large-distance, long-time asymptotics for Brownian motion are calculated by using a nonlinear stochastic Navier-Stokes equation including the effect of friction with the substrate. The advective nonlinearity, neglected in previous treatments, gives only a small correction to the renormalized viscosity and diffusion coefficient at room temperature. We find, however, that in realistic multicomponent lipid mixtures, close to a critical point for phase separation, protein diffusion acquires a strong power-law dependence on temperature and the distance to the substrate H, making it much more sensitive to cell environment, unlike the logarithmic dependence on H and very small thermal correction away from the critical point.
我们研究了在靠近刚性基底的多组分脂质膜中的蛋白质扩散，该刚性基底由一层粘性流体隔开。通过使用包含与基底摩擦效应的非线性随机纳维 - 斯托克斯方程来计算布朗运动的大距离、长时间渐近性。在先前的处理中被忽略的平流非线性，在室温下对重整化粘度和扩散系数仅给出很小的修正。然而，我们发现，在实际的多组分脂质混合物中，接近相分离临界点时，蛋白质扩散对温度和到基底的距离(H)呈现出强烈的幂律依赖性，这使其对细胞环境更为敏感，这与远离临界点时对(H)的对数依赖性以及非常小的热修正不同。
