Cross-linking of DNA in situ as a probe for chromatin structure

Science  02 Jul 1976:
Vol. 193, Issue 4247, pp. 62-64
DOI: 10.1126/science.935855


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.