Yeast nucleosomes allow thermal untwisting of DNA.
AUTOR(ES)
Morse, R H
RESUMO
Thermal untwisting of DNA is suppressed in vitro in nucleosomes formed with chicken or monkey histones. In contrast, results obtained for the 2 micron plasmid in Saccharomyces cerevisiae are consistent with only 30% of the DNA being constrained from thermal untwisting in vivo. In this paper, we examine thermal untwisting of several plasmids in yeast cells, nuclei, and nuclear extracts. All show the same quantitative degree of thermal untwisting, indicating that this phenomenon is independent of DNA sequence. Highly purified yeast plasmid chromatin also shows a large degree of thermal untwisting, whereas circular chromatin reconstituted using chicken histones is restrained from thermal untwisting in yeast nuclear extracts. Thus, the difference in thermal untwisting between yeast chromatin and that assembled with chicken histones is most likely due to differences in the constituent histone proteins.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=339946Documentos Relacionados
- Nucleosome core particles suppress the thermal untwisting of core DNA and adjacent linker DNA.
- Formation of nucleosomes on positively supercoiled DNA.
- Thermal stability of DNA.
- Transferring DNA from electrophoretically resolved nucleosomes to diazobenzyloxymethyl cellulose: properties of nucleosomes along mouse satellite DNA.
- Strand breakage by the DNA untwisting enzyme results in covalent attachment of the enzyme to DNA.
