AI Article Synopsis
- Gene regulation is mainly influenced by the structure of individual chromatin molecules, but most studies have focused on broad samples rather than on specific molecules.
- Researchers created a new method called Fiber-seq to capture the precise structure of single chromatin fibers by using DNA methyltransferases for detailed analysis.
- This technique revealed significant flexibility in how chromatin fibers are organized and provided insights into how regulatory elements interact, nucleosomes are positioned, and transcription factors bind.
Article Abstract
Gene regulation is chiefly determined at the level of individual linear chromatin molecules, yet our current understanding of cis-regulatory architectures derives from fragmented sampling of large numbers of disparate molecules. We developed an approach for precisely stenciling the structure of individual chromatin fibers onto their composite DNA templates using nonspecific DNA N-adenine methyltransferases. Single-molecule long-read sequencing of chromatin stencils enabled nucleotide-resolution readout of the primary architecture of multikilobase chromatin fibers (Fiber-seq). Fiber-seq exposed widespread plasticity in the linear organization of individual chromatin fibers and illuminated principles guiding regulatory DNA actuation, the coordinated actuation of neighboring regulatory elements, single-molecule nucleosome positioning, and single-molecule transcription factor occupancy. Our approach and results open new vistas on the primary architecture of gene regulation.
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| http://dx.doi.org/10.1126/science.aaz1646 | DOI Listing |
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