細(xì)胞要進(jìn)行重要的生理代謝功能，主要的就是得接收與傳遞細(xì)胞內(nèi)外的訊號(hào)，而參與這個(gè)過(guò)程的重要關(guān)鍵角色,，就是位于細(xì)胞膜上的蛋白質(zhì),，科學(xué)家雖然知道，膜上蛋白參與的生理機(jī)能非常的復(fù)雜,，但透過(guò)新一代計(jì)算機(jī)技術(shù)的幫忙,，很可能解開(kāi)一些目前實(shí)驗(yàn)科學(xué)所不能回答的疑問(wèn)。
這次科學(xué)家在著名的科學(xué)期刊 PLoS計(jì)算器生物學(xué) (Computational Biology)上,，發(fā)表一份最新的研究報(bào)告指出,，由 Tristan Ursell博士所領(lǐng)導(dǎo)的研究團(tuán)隊(duì)，透過(guò)計(jì)算機(jī)程序的模擬,，深入的分析膜上蛋白質(zhì)可能存在的動(dòng)力學(xué)行為,，研究人員利用程序仿真膜上蛋白質(zhì)的行為，發(fā)現(xiàn)細(xì)胞膜的表面可以非常的具有彈性,，并且透過(guò)厚薄的改變,，來(lái)包埋膜上的蛋白質(zhì)，輔助膜上蛋白質(zhì)的溝通功能,，甚至像是提供離子通透的孔徑蛋白,，也是透過(guò)細(xì)胞膜的彈性來(lái)輔助變形的過(guò)程。
由這次的研究報(bào)告,，證實(shí)了細(xì)胞膜脂質(zhì)雙層的彈性結(jié)構(gòu),，確實(shí)提供了膜上蛋白質(zhì)的構(gòu)成條件，輔助組織生理功能與代謝的過(guò)程,。
（編譯/許仁旗） (資料來(lái)源 : biocompare)
英文原文鏈接：
http://news.biocompare.com/newsstory.asp?id=181263
原始出處：
Cooperative Gating and Spatial Organization of Membrane Proteins through Elastic Interactions
Tristan Ursell1, Kerwyn Casey Huang2, Eric Peterson3, Rob Phillips1,4*
1 Department of Applied Physics, California Institute of Technology, Pasadena, California, United States of America, 2 Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America, 3 Department of Physics, California Institute of Technology, Pasadena, California, United States of America, 4 Kavli Nanoscience Institute, Pasadena, California, United States of America
Biological membranes are elastic media in which the presence of a transmembrane protein leads to local bilayer deformation. The energetics of deformation allow two membrane proteins in close proximity to influence each other's equilibrium conformation via their local deformations, and spatially organize the proteins based on their geometry. We use the mechanosensitive channel of large conductance (MscL) as a case study to examine the implications of bilayer-mediated elastic interactions on protein conformational statistics and clustering. The deformations around MscL cost energy on the order of 10 kBT and extend 3 nm from the protein edge, as such elastic forces induce cooperative gating, and we propose experiments to measure these effects. Additionally, since elastic interactions are coupled to protein conformation, we find that conformational changes can severely alter the average separation between two proteins. This has important implications for how conformational changes organize membrane proteins into functional groups within membranes.
Funding. The authors received no specific funding for this study.
Competing interests. The authors have declared that no competing interests exist.
Editor: Andrej Sali, University of California San Francisco, United States of America
Citation: Ursell T, Huang KC, Peterson E, Phillips R (2007) Cooperative Gating and Spatial Organization of Membrane Proteins through Elastic Interactions. PLoS Comput Biol 3(5): e81 doi:10.1371/journal.pcbi.0030081
Received: February 5, 2007; Accepted: March 21, 2007; Published: May 4, 2007
Copyright: © 2007 Ursell et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Abbreviations: MscL, mechanosensitive channel of large conductance
* To whom correspondence should be addressed. E-mail: [email protected]
Author Summary
Membranes form flexible boundaries between the interior of a cell and its surrounding environment. Proteins that reside in the membrane are responsible for transporting materials and transmitting signals across these membranes to regulate processes crucial for cellular survival. These proteins respond to stimuli by altering their shape to perform specific tasks, such as channel proteins, which allow the flow of ions in only one conformation. However, the membrane is not just a substrate for these proteins, rather it is an elastic medium that bends and changes thickness to accommodate the proteins embedded in it. Thus, the membrane plays a role in the function of many proteins by affecting which conformation is energetically favorable. Using a physical model that combines membrane elastic properties with the structure of a typical membrane protein, we show that the membrane can communicate structural and hence conformational information between membrane proteins in close proximity. Hence, proteins can “talk” and “respond” to each other using the membrane as a generic “voice.” We show that these membrane-mediated elastic forces can ultimately drive proteins of the same shape to cluster together, leading to spatial organization of proteins within the membrane.
