| Autor: |
Ulanovsky LE, Trifonov EN |
| Jazyk: |
angličtina |
| Zdroj: |
Cell biophysics [Cell Biophys] 1983 Dec; Vol. 5 (4), pp. 281-3. |
| DOI: |
10.1007/BF02788626 |
| Abstrakt: |
Winding DNA in a superhelix can be considered a process consisting of two smooth deformations: bending and twisting. The extra twist angle introduced by winding DNA into the nucleosomal superhelix is calculated by means of the Crick formula to be -0.5 degrees per base pair (bp). This is equivalent to a change of -0.15 +/- 0.015 bp in the DNA double-helical repeat. Free DNA in solution is known to have a helical repeat of 10.55 +/- 0.1 bp. On the other hand, a weighted average of various estimates of the DNA repeat in the nucleosome is 10.38 +/- 0.02. The difference happens to be perfectly accounted for by the superhelicity of the nucleosomal DNA. This implies that the latter is essentially nonconstrained . |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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