通过核酸酶消化研究可渗透肉瘤细胞中的复制性DNA合成和非程序性DNA合成。

Replicative DNA synthesis and unscheduled DNA synthesis in permeable sarcoma cells studied by nuclease digestion.

作者信息

Seki S, Watanabe S, Oda T

出版信息

Biochim Biophys Acta. 1980 Mar 28;607(1):36-42. doi: 10.1016/0005-2787(80)90218-x.

Abstract

About 20% of DNA replicated in vitro in permeable mouse ascites sarcoma cells showed higher sensitivity to staphylococcal nuclease than the sensitivity of bulk DNA, and the remaining part showed the same nuclease sensitivity as that of parental chromatin DNA. The sensitivity of DNA replicated in permeable cells was higher than that of DNA newly replicated in vivo in intact cells, and close to that of DNA newly replicated in vivo in the presence of cycloheximide. Bleomycin-induced unscheduled DNA synthesis in permeable cells was highly sensitive to the nuclease. The results suggest that DNA replicated in vitro and parental nuclear protein form immature nucleosomes, probably in the same way as in vivo chromatin replication in the presence of protein synthesis inhibitors. It also appears that bleomycin-induced, unscheduled DNA synthesis occurs largely in the internucleosomal region.

摘要

在可渗透的小鼠腹水肉瘤细胞中体外复制的DNA，约20%对葡萄球菌核酸酶的敏感性高于总体DNA，其余部分对核酸酶的敏感性与亲本染色质DNA相同。在可渗透细胞中复制的DNA的敏感性高于完整细胞中体内新复制的DNA，且接近在环己酰亚胺存在下体内新复制的DNA的敏感性。博来霉素诱导的可渗透细胞中的DNA非预定合成对核酸酶高度敏感。结果表明，体外复制的DNA与亲本核蛋白形成未成熟的核小体，可能与存在蛋白质合成抑制剂时体内染色质复制的方式相同。还似乎博来霉素诱导的DNA非预定合成主要发生在核小体间区域。