DNA-STRUCTURE - EVIDENCE FROM ELECTRON-MICROSCOPY
DNA-STRUCTURE - EVIDENCE FROM ELECTRON-MICROSCOPY
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DOI：
10.1126/science.663672
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发表时间：
1978-01-01
期刊：
影响因子：
56.9
通讯作者：
GRIFFITH, JD
中科院分区：
文献类型：
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作者：
GRIFFITH, JD
用几种常用的EM技术测量了vphi.X174 DNA双链和RNA-DNA杂化分子的轮廓长度。杂化分子的外周长度对应于2.5-2.6 ng/碱基对的上升，如对于A构象的预期，而类似测量的vphi.X174双链DNA的长度对应于2.9 ANG.上升，与经典B型的3.4ANG.非常不同。因此，任何基于EM和上升3.4ANG.的染色质结构参数都必须重新评估。讨论了DNA在稀溶液中也有2.9°上升和一个10.5碱基对/转的螺杆的可能性。
The contour lengths of .vphi.X174 DNA duplex and RNA-DNA hybrid molecules were measured by several commonly used EM techniques. The countour length of the hybrid molecules corresponds to a rise of 2.5-2.6 .ANG./base pair, as expected for the A conformation, while the length of .vphi.X174 duplex DNA similarly measured corresponds to a 2.9 .ANG. rise, very different from 3.4 .ANG. of the classic B form. Thus any chromatin structure parameter based on EM and a rise of 3.4 .ANG. must be reappraised. The possibility that DNA in dilute solution also has a rise of 2.9 .ANG. and a screw of 10.5 base pairs/turn is discussed.