Compromised two-start zigzag chromatin folding in immature mouse retina cells driven by irregularly spaced nucleosomes with short DNA linkers.

ABSTRACT: The formation of condensed heterochromatin is critical for establishing cell-specific transcriptional programs. To reveal structural transitions underlying heterochromatin formation in maturing mouse rod photoreceptors, we apply cryo-electron microscopy (cryo-EM) tomography, AI-assisted denoising, and molecular modeling. We find that chromatin isolated from immature retina cells contains many closely apposed nucleosomes with extremely short or absent nucleosome linkers, which are inconsistent with the typical two-start zigzag chromatin folding. In mature retina cells, the fraction of short-linker nucleosomes is much lower, supporting stronger chromatin compaction. By cryo-EM-assisted nucleosome interaction capture, we observe that chromatin in immature retina is enriched with i ± 1 interac

SUBMITTER: Kable B 

PROVIDER: S-EPMC12135184 | biostudies-literature | 2025 May

REPOSITORIES: biostudies-literature