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Updated: Jun 26, 2026
Deciphering Molecular Mechanism of Histone Assembly by DNA Curtain Technique
Published on: March 9, 2022
High-resolution dynamic mapping of histone-DNA interactions in a nucleosome
Michael A Hall1, Alla Shundrovsky, Lu Bai
1Department of Physics-Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA.
Abstract:
The nature of the nucleosomal barrier that regulates access to the underlying DNA during many cellular processes is not fully understood. Here we present a detailed map of histone-DNA interactions along the DNA sequence to near base pair accuracy by mechanically unzipping single molecules of DNA, each containing a single nucleosome. This interaction map revealed a distinct approximately 5-bp periodicity that was enveloped by three broad regions of strong interactions, with the strongest occurring at the dyad and the other two about +/-40-bp from the dyad. Unzipping up to the dyad allowed recovery of a canonical nucleosome upon relaxation of the DNA, but unzipping beyond the dyad resulted in removal of the histone octamer from its initial DNA sequence. These findings have important implications for how RNA polymerase and other DNA-based enzymes may gain access to DNA associated with a nucleosome.
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