Braun B A, Schanke K E, Graham D E
Nucleic Acids Res. 1978 Nov;5(11):4283-304. doi: 10.1093/nar/5.11.4283.
Sequences that did or did not reassociate at 75 dagrees C (stable and unstable, respectively) were isolated from total repetitive Xenopus laevis DNA. Sequence complexities or frequencies were determined by self (minicot) or DNA excess (slave minicot) reassociations at 60 degrees C. Stable sequences were five times shorter and four times more frequent than unstable sequences. Reassociations at 75 degrees C or at 50 degrees C were used to establish apparent sequence frequencies at these criteria. Interspersion curves at either 60 degrees C or 75 degrees C and low Cot reassociation of long fragments of total X. laevis DNA at either 60 degrees C or 75 degrees C, followed by S1 digestion and agarose chromatography, were used to determine genome arrangement of the stable and unstable classes of sequence. Reassociation at high temperature was found to permit the fractionation of repetitive sequences into two populations of differing characteristics.
从非洲爪蟾总的重复DNA中分离出在75℃时发生或未发生重新缔合的序列（分别为稳定序列和不稳定序列）。通过在60℃下进行自身（微量）或DNA过量（从属微量）重新缔合来确定序列复杂性或频率。稳定序列比不稳定序列短五倍且频率高四倍。在75℃或50℃下的重新缔合用于确定这些条件下的表观序列频率。在60℃或75℃下的散布曲线以及在60℃或75℃下对非洲爪蟾总DNA长片段进行的低Cot重新缔合，随后进行S1消化和琼脂糖层析，用于确定稳定和不稳定序列类别的基因组排列。发现高温下的重新缔合能够将重复序列分成具有不同特征的两个群体。
