Organization and transcriptional activity of brain chromatin subunits

Digestion of brain nuclei with micrococcal nuclease produces 11.2-S chromatin subunits which comprise up to 80% of the total nuclear DNA. Hybridization studies with excess subunit DNA demonstrate that subunits are distributed throughout the repeated and nonrepeated sequences of the genome. No class of nonrepeated DNA appears to be excluded from subunits. Transcribed DNA is present in chromatin subunits since in vitro labelled poly(A+)-mRNA hybridizes to excess subunit DNA with kinetics identical to that for total DNA.