Condensation of polynucleosome by histone H1 binding

FEBS Letters

Watanabe, Fumiyuki¹ 

[1] Department of Biophysical Chemistry, Biocenter, University of Basel, Klingelbergstrasse 70, CH-4056 Basel, Switzerland

关键词: Polynucleosome;    Histone H1;    Cooperativity;    Kinetics;   

DOI  :  10.1016/0014-5793(84)81360-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The cooperative binding of histone H1 to polynucleosome was studied quantitatively. The equilibrium and kinetic data were satisfactorily described in terms of the large ligand model. The binding constant K and the cooperativity parameter q showed remarkable salt effects: K = 7.5 × 10⁷ M⁻¹ and q = 1.3 × 10⁴ at 0.2 M NaCl, pH 7.5 and 20°C. This considerably strong cooperativity reveals that the polynucleosome state, condensed or not, is sensitive to small changes in he free histone H1 concentration around the value of 1/K. The association rate constant was of the order of 10⁷ M⁻¹·s⁻¹ and had a small salt concentration dependence, indicating a diffusion-controlled association process.

【 授权许可】

Unknown