The photoaddition of trimethylpsoralen to Drosophila melanogaster nuclei: a probe for chromatin substructure.
The photoaddition of trimethylpsoralen to Drosophila melanogaster nuclei: a probe for chromatin substructure.
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三甲基补骨脂素与果蝇细胞核的光加成：染色质亚结构的探针。
DOI：
10.1021/bi00624a018
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发表时间：
1977
期刊：
影响因子：
2.9
通讯作者：
J. Hearst
中科院分区：
文献类型：
--
作者：
G. P. Wieshahn;J. E. Hyde;J. Hearst
呋喃并香豆素的衍生物，即香豆素，可以穿透完整的细胞或细胞核，并在长波长紫外光的影响下交联染色体DNA的相对链。本文研究了trioxsalen（4，5 ′，8-trimethylpepsilen）作为染色质结构探针的可能性。发现相对于纯化的DNA，来自黑腹果蝇的胚胎细胞核和组织培养细胞中的DNA被保护约90%免于三氧沙林结合。通过微球菌核酸酶消化经三恶沙林处理的细胞核，并对所得DNA进行凝胶电泳，得到相同类型的带型，这是天然未处理细胞核消化的特征。因此，使用核酸酶消化来检查结合的trioxsalen在DNA中的分布。通过放射性测量和定量电子显微镜分析所得DNA片段。核酸酶切割完整的光反应的细胞核，以这样一种方式，优先切除的trioxsalen含有区域的DNA发生，但是，当作用于纯化的DNA，含有bount trioxsalen，它攻击的trioxsalen的自由区域优先。因此得出结论，曲沙仑结合在对应于细胞核中染色质的常规核酸酶敏感区域的位点。
Derivatives of the furocoumarin, psoralen, can penetrate intact cells or nuclei and cross-link opposite strands of the chromosomal DNA under the influence of long wave-length ultraviolet light. The potential of trioxsalen (4,5',8-trimethylpsoralen) as a probe for chromatin structure has been investigated. The DNA in both embryo nuclei and tissue culture cells from Drosophila melanogaster was found to be about 90% protected from trioxsalen binding relative to purified DNA. Digestion of trioxsalen-treated nuclei by micrococcal nuclease and gel electrophoresis of the resulting DNA gave the same type of band pattern that is characteristic of native, untreated nuclei are digestion. Nuclease digestion was therefore used to examine the distribution of bound trioxsalen in the DNA. The resulting DNA fragments were analyzed both by radioactivity measurements and quantitative electron microscopy. The nuclease cleaved intact photoreacted nuclei in such a way that preferential excision of trioxsalen containing regions of the DNA occurred, but, when acting upon purified DNA that contained bount trioxsalen, it attacked the trioxsalen-free regions preferentially. It was thus concluded that trixosalen binds at the sites corresponding to the regular nuclease-sensitive regions of the chromatin in nuclei.