Nucleosomes are the basic unit of chromatin, but genome-scale maps of nucleosome positioning along chromatin fibers do not exist for brain and many other complex tissues. Conventional chromatin accessibility assays designed to map nucleosome-depleted regions via nucleolytic digestion face major limitations such as limited resolution and sequence bias, with additional shortcomings from PCR-generated short-read libraries including poor annotation for an estimated 50% of the human genome. To address this, we tested a brain-adapted single-molecule chromatin fiber sequencing (Fiber-seq) protocol designed for amplification-free adenine-methyltransferase tagging of extranucleosomal DNA in neuronal and, separately, non-neuronal nuclei in situ.
Journal: Cell Symposia
DOI: 10.1016/j.crmeth.2024.100911
Year: 2024