Chromatin fiber polymorphism triggered by variations of DNA linker lengths

• DOI: 10.1073/pnas.1315872111
• Publication Date: 2014-05-21T01:53:54Z
• Authors: Rosana Collepardo...; Tamar Schlick
• Keywords: 0301 basic medicine; Polymorphism, Genetic; Static Electricity; Molecular Conformation; DNA; Chromatin; Nucleosomes; Rats; Histones; 03 medical and health sciences; Gene Expression Regulation; Models, Chemical; Animals; Nucleic Acid Conformation; Protein Structure, Quaternary; Algorithms

Significance The structure of the chromatin fiber remains one of the most fundamental open biological questions because structure dictates many template-directed processes. We use coarse-grained modeling to investigate systematically how variations in the linker DNA length that arise naturally for chromatin in different tissues, species, and cell cycle stages affect fiber architecture. We unravel a natural source of fiber polymorphism, in which irregular interdigitated 10-nm and compact 30-nm fibers coexist. These results suggest how structural diversity can be advantageous for gene regulation activity. Interesting DNA design applications also arise.