Attardi B, Attardi G
Proc Natl Acad Sci U S A. 1972 Jan;69(1):129-33. doi: 10.1073/pnas.69.1.129.
Several hybrid lines between human and mouse somatic cells, containing one or two complements of mouse chromosomes and a reduced complement of human chromosomes, have been examined for the presence of mouse and human mitochondrial DNAs. For this analysis, advantage was taken of the fact that these two types of mitochondrial DNA have a buoyant density difference in CsCl gradients of 0.008 g/cm(3). In all the hybrid clones analyzed, which retained an average number of human chromosomes estimated conservatively to vary from 5 to 23, only mitochondrial DNA of mouse character was detected. It seems likely that either repression of relevant human genes by the mouse genome or loss of human chromosomes is responsible for these results. If the latter explanation is true, since chromosome loss under the conditions used here was substantially a random process, one would have to assume that the activity of nuclear genes distributed in many chromosomes is required for the survival of mitochondrial DNA.
人们已经对几种人与小鼠体细胞的杂交细胞系进行了检测，这些细胞系含有一或两套小鼠染色体以及数量减少的人类染色体，以确定其中是否存在小鼠和人类的线粒体DNA。在这项分析中，利用了这样一个事实：这两种类型的线粒体DNA在氯化铯梯度中的浮力密度相差0.008 g/cm³。在所有分析的杂交克隆中，保守估计保留的人类染色体平均数在5到23条之间，结果只检测到了具有小鼠特征的线粒体DNA。这些结果似乎可能是由于小鼠基因组对相关人类基因的抑制作用，或者是人类染色体的丢失所致。如果后一种解释是正确的，由于在这里所用条件下染色体丢失基本上是一个随机过程，那么就必须假定，分布在许多染色体上的核基因的活性是线粒体DNA存活所必需的。
