Chromatin Accessibility as a Strategy to Detect Changes Associated With Development, Disease, and Exposure and Susceptibility to Chemical Toxins

Abstract In addition to their role in chromatin architecture, nucleosomes create a barrier to DNA-templated processes. The placement of nucleosomes creates organization in the chromatin that influences transcriptional activation, DNA damage repair, replication, RNA processing, and nuclear organization. However, nucleosome positioning is not random. Multiple cellular factors converge to control precise nucleosomal location and spacing. Intricately linked to the overall regulatory environment specific to each cell lineage, chromatin organization offers an unbiased overview of the epigenetic influences associated with cellular replication, development, differentiation, and disease. Here, we review the utility of chromatin architecture in understanding both intrinsic and extrinsic mechanisms affecting normal development and diseases and outline assays that are currently available to interrogate in vivo chromatin accessibility.