大分子拥挤对DNA结构的影响  

The Impact of Macromolecular Crowding Effect on the Formation of DNA Structure

作　　者：钟文涛[1] 洪美亚[1] 龚兴国[1] 

机构地区：[1]浙江大学生命科学学院生物大分子与酶工程研究所,杭州310027

出　　处：《细胞生物学杂志》2004年第6期583-586,共4页Chinese Journal of Cell Biology

摘　　要：大分子拥挤(macromolecular crowding effect)代表了细胞内高度拥挤状态,其源于非特异性容积排斥效应,是细胞内与pH、离子强度等同等重要的生理因素。生物大分子介导的拥挤环境对于DNA-DNA、DNA-蛋白质的相互作用以及DNA高级结构、细胞核或核区结构的稳定具有重要作用。在拥挤环境中,大分子总浓度的增加将增强溶质的浓缩倾向,从而降低溶液的自由能。拥挤效应是胞内大分子环境的,总体反映,具有高度的缓冲性,保证了胞内反应的稳定进行及细胞功能的正常行使。Macromolecular crowding effect, which developed from the theory of volume excluded effect, represents a ubiquitous highly crowded condition in living cells and plays an equally important role in cellular physiology with pH value, ionic strength, etc. Crowding agents, such as polyethylene glycol (PEG), significantly functions in the interactions of DNA-DNA or DNA-protein, and stabilizes the formation of higher-order structure of DNA and nucleolus or nuclear area. Macromolecules in crowded environment have an intrinsic tendency of association and aggregation, which arises with the concentration of the macromolecules and reduces the free energy of the solvent by leading solutes to smaller volume. The buffering capacity of macromolecular crowding exceedingly maintains the intracellular physiological condition, ensuring the normal function of living cells.

关 键 词：大分子拥挤 DNA结构 拥挤效应 生物大分子 拥挤试剂 缓冲性 

分 类 号：Q523[生物学—生物化学]