title: Cross-linking of DNA in situ as a probe for chromatin structure.
abstract: The photochemical cross-linking of DNA in situ in chromatin is blocked over short intervals. Electron microscopy of DNA cross-linked in chromatin reveals the lengths of protected regions and provides a map of their sites along the DNA. Protected regions occur most frequently in tandem and have a basic length of 160 to 200 base pairs.
mesh_terms: D000818:Animals; D002843:Chromatin / Q000648:ultrastructure*; D003374:Coumarins; D004247:DNA; D004330:Drosophila; D005363:Ficusin; D008854:Microscopy, Electron; D010777:Photochemistry
chemical_list: D002843:Chromatin; D003374:Coumarins; D004247:DNA; D005363:Ficusin