Role of histone H1 in the conformation of oligonucleosomes as a function of ionic strength

Thyroid hormone receptor-containing fragment released from chromatin by deoxyribonuclease I and micrococcal nuclease

Limited deoxyribonuclease I and micrococcal nuclease digestion of hepatic nuclei from euthyroid rats injected with 125I-labeled triiodothyronine ([125I]T3) releases a discrete [125I]T3-labeled chromatin fragment (5.8S) which is larger than the T3 receptor (3.5S). These results suggest the T3 receptor is associated with a restricted fraction of hepatic chromatin that has a nuclease sensitivity characteristic of transcriptionally active chromatin.

On the chromatin structure of Trypanosoma cruzi

The chromatin structure of Trypanosoma cruzi was investigated. It was found that, as in other eukaryotes, the chromatin is organized in repeating units, the nucleosomes containing about 200 base pairs of DNA associated with histones. While there is no difference in the DNA size in nucleosomes from T. cruzi and from rat liver nuclei, the histone population of T. cruzi differs in various aspects. Of particular interest is the presence of two basic proteins, possibly histone H1 subcomponents, with very high electrophoretic mobilities.