| Autor: |
Osipova, Tatyana N., Pospelov, Valeri A., Svetlikova, Svetlana B., Vorob'ev, Vladimir I. |
| Předmět: |
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| Zdroj: |
European Journal of Biochemistry; 12/15/80, Vol. 113 Issue 1, p183-188, 6p |
| Abstrakt: |
The dependence of sedimentation coefficients of oligonucleosomes on the number of nucleosomes in the chain in solutions of different ionic strength has been studied for oligonucleosomes both containing and lacking histone H 1. The analysis of these dependencies has shown that oligo- nucleosomes with H I at low concentration (1=0.01 mol/l) may be described by the model of a short cylinder with an average length of the chain per nucleosome l0 =11 nm where the neighbouring nucleosomes are in close contact, Oligonucleosomes without H I at 1=0.01 mol/1 can be described by the model of a worm-like chain with l0 =27 nm. This suggests that when H 1 is removed the linker DNA unfolds completely. In 0.15 M NaCl the oligonucleosome chain without H 1 folds up to a compact configuration typical of oligonucleosomes with H I at 1=0.01 mol/l. Thus, the linker DNA, with charges being screened, may fold due to interactions with core histones. Oligonucleosomes with H 1 in 0.15 M NaCl form a supercoiled structure, whose stable conformation is accounted for by cooperative interactions of no less than five nucleosomes. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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