Rinehart F P, Ritch T G, Deininger P L, Schmid C W
Biochemistry. 1981 May 26;20(11):3003-10. doi: 10.1021/bi00514a003.
We have investigated the renaturation kinetics of a single family of cloned interspersed repeated sequences isolated from human DNA. Cross-renaturation studies of individual cloned sequences reveal heterogeneity in both the renaturation rate and the thermal stability of heteroduplexes formed from members of this family of sequences. However, cloned members of this family all renature with approximately the same number of copies in the human genome, demonstrating that they are a single family of sequences by the criterion of DNA renaturation kinetics. When a single cloned member of the family is renatured with total human DNA as a function of temperature, the thermal stability of the renatured heteroduplexes is found to be independent of the renaturation temperature over the range 25 degrees C below to 4 degrees C above the melting temperature. Further, the number of genomic copies with which this cloned family member reacts is also independent of the renaturation temperature from 25 degrees C below up to the melting temperatures. These observations demonstrate a remarkable degree of homogeneity in the evolutionary sequence divergence of members of this family. These results also demonstrate that renaturation kinetics can accurately measure the number of genomic copies of interspersed repeated DNA sequences.
我们研究了从人类DNA中分离出的单个克隆散布重复序列家族的复性动力学。对单个克隆序列的交叉复性研究表明，该序列家族成员形成的异源双链体在复性速率和热稳定性方面均存在异质性。然而，该家族的克隆成员在人类基因组中的复性拷贝数大致相同，这表明根据DNA复性动力学标准，它们是一个单一的序列家族。当该家族的单个克隆成员与总人类DNA一起随温度进行复性时，发现复性异源双链体的热稳定性在低于解链温度25摄氏度至高于解链温度4摄氏度的范围内与复性温度无关。此外，该克隆家族成员与之反应的基因组拷贝数在低于25摄氏度直至解链温度的范围内也与复性温度无关。这些观察结果表明该家族成员在进化序列分歧方面具有显著的同质性。这些结果还表明，复性动力学可以准确测量散布重复DNA序列的基因组拷贝数。
