Superstructure and CD spectrum as probes of chromatin integrity.
AUTOR(ES)
de Murcia, G
RESUMO
Two types of chromatin were extracted from the same stock of rat liver nuclei by a short exposure to micrococcal nuclease and by shearing respectively. These two materials which are identical in their protein/DNA content and by the presence of the five histones, were compared by means of circular dichroism and electron microscopy. Under the electron microscope and in absence of any divalent cation a superstructure of the unfixed chromatin fiber can be viewed only with native material but is no more present in sheared one. The increase of CD signal at 280 nm (from 2000 to about 4000 cm2 deg.dmole-1) in the case of sheared chromatin is not related to the loss of superstructure but to the structural changes of DNA inside the nucleosomal core which are always produced by shearing. These two correlated observations offer new sensitive probes of the integrity of any native or reconstituted chromatin.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=341999Documentos Relacionados
- 'Superstructure and CD spectrum as probes of chromatin integrity'
- Professional integrity.
- Solenoidal model for superstructure in chromatin.
- Aflatoxin contamination in soybeans: role of proteinase inhibitors, zinc availability, and seed coat integrity.
- The 4th World Conference on Research Integrity. Research Integrity and Rewards: Improving Systems to Promote Responsible Research
