Callen J C, Dennebouy N, Mounolou J C
J Cell Sci. 1980 Feb;41:307-20. doi: 10.1242/jcs.41.1.307.
The development of the mitochondrial mass of the previtellogenic oocytes of Xenopus laevis has been analysed by a morphometric method and it has been correlated with the growth of the occyte itself. The study which was performed with oocytes from females of very different ages shows that the relative size of the mitochondrial mass in the smallest oocytes decreases gradually with the age of the females. Cytophotometric analysis of the Feulgen-stained mitochondrial mass enabled the mtDNA content of that structure to be quantified during its development. This development involves about 12 rounds of replication out of the total 16--17 rounds of replication during complete differentiation of large oocytes. It is possible to estimate the mean replication rate of the mtDNA during the course of the previtellogenic period. The calculated rate of replication is very high in the mitochondrial mass of all the growing oocytes of very young females(about 1--2 months old), then it decreases rapidly when the oocytes reach 120 microns in diameter. These results suggest that the mitochondrial masses found in small oocytes of old females do not correspond to sites of active mitochondrial biogenesis but rather they represent a physiologically arrested collection of organelles. Thus the aggregation of mitochondria is the cytological expression of rapid and strictly localized mitochondriogenesis only in very young females.
利用形态测量法分析了非洲爪蟾卵黄生成前卵母细胞线粒体质量的发育情况，并将其与卵母细胞自身的生长进行了关联。对来自不同年龄雌性的卵母细胞进行的研究表明，最小卵母细胞中线粒体质量的相对大小会随着雌性年龄的增长而逐渐减小。对经福尔根染色的线粒体质量进行细胞光度分析，能够在其发育过程中对该结构的线粒体DNA含量进行定量。在大卵母细胞完全分化的总共16 - 17轮复制过程中，这种发育涉及约12轮复制。可以估算卵黄生成前期线粒体DNA的平均复制速率。在非常年轻的雌性（约1 - 2个月大）所有生长中的卵母细胞的线粒体质量中，计算出的复制速率非常高，然后当卵母细胞直径达到120微米时，复制速率迅速下降。这些结果表明，老龄雌性小卵母细胞中的线粒体质量并非活跃线粒体生物发生的部位，而是代表了细胞器在生理上的停滞聚集。因此，线粒体的聚集只是非常年轻雌性中快速且严格定位的线粒体生成的细胞学表现。
