Angle between DNA linker and nucleosome core particle regulates array compaction revealed by individual-particle cryo-electron tomography.

ABSTRACT: The conformational dynamics of nucleosome arrays generate a diverse spectrum of microscopic states, posing challenges to their structural determination. Leveraging cryogenic electron tomography (cryo-ET), we determine the three-dimensional (3D) structures of individual mononucleosomes and arrays comprising di-, tri-, and tetranucleosomes. By slowing the rate of condensation through a reduction in ionic strength, we probe the intra-array structural transitions that precede inter-array interactions and liquid droplet formation. Under these conditions, the arrays exhibite irregular zig-zag conformations with loose packing. Increasing the ionic strength promoted intra-array compaction, yet we do not observe the previously reported regular 30-nanometer fibers. Interestingly, the presence of H1

SUBMITTER: Zhang M 

PROVIDER: S-EPMC11116431 | biostudies-literature | 2024 May

REPOSITORIES: biostudies-literature