天然和重组染色质中核小体的稳定性

Germond J E, Bellard M, Oudet P, Chambon P

Nucleic Acids Res. 1976 Nov;3(11):3173-92. doi: 10.1093/nar/3.11.3173.

The stability of nucleosomes of SV40 minichromosomes extracted from infected cells or reconstituted by association of SV40 DNA and the four histones H2A, H2B, H3 and H4 was studied as a function of the ionic strength. As a measure of the stability of the nucleosome, we followed the disappearance of the nucleosomes from the original chromatin and their appearance on a "competing" DNA. We show here that the DNA and the histone components of the nucleosomes do not apprecially dissociate below 800 mM NaCl. At 800 mM and above, the histone moiety of the nucleosomes can dissociate from the DNA and efficiently participate to the formation of nucleosomes on a "competing" DNA.

研究了从感染细胞中提取的或通过SV40 DNA与四种组蛋白H2A、H2B、H3和H4结合重建的SV40微型染色体的核小体稳定性与离子强度的关系。作为核小体稳定性的一种衡量方法，我们跟踪了原始染色质中核小体的消失以及它们在“竞争”DNA上的出现。我们在此表明，在低于800 mM NaCl的情况下，核小体的DNA和组蛋白成分不会明显解离。在800 mM及以上时，核小体的组蛋白部分可以从DNA上解离，并有效地参与在“竞争”DNA上形成核小体。