Blamire J, Flechtner V R, Sager R
Proc Natl Acad Sci U S A. 1974 Jul;71(7):2867-71. doi: 10.1073/pnas.71.7.2867.
The experiments described in this paper implicate chloroplast protein synthesis in the regulation of nuclear DNA replication. The inhibition of nuclear DNA replication in the lower eukaryote, Chlamydomonas reinhardi strain 21gr, was examined after growth of cells with a series of antibiotics (streptomycin, neamine, spectinomycin, cleocin, chloramphenicol, and rifampicin) each of which has a known effect upon chloroplast RNA or protein synthesis in this organism. Each antibiotic inhibited nuclear DNA replication at drug concentrations at which there was little or no inhibition of adenine incorporation into chloroplast DNA. That chloroplast DNA was replicating under these conditions rather than merely being repaired, was shown first by the high incorporation rates and second by a (14)N-(15)N density transfer experiment in which chloroplast DNA doubled in the presence of streptomycin, while no incorporation into nuclear DNA was detected. A small DNA peak, Component III, located between nuclear and chloroplast DNA's in CsCl gradients, possibly mitochondrial, was more pronounced in DNA from antibiotic-inhibited cultures than from controls.
本文所述实验表明叶绿体蛋白质合成参与了核DNA复制的调控。在用一系列抗生素（链霉素、新霉素、壮观霉素、氯洁霉素、氯霉素和利福平）培养莱茵衣藻21gr菌株（一种低等真核生物）的细胞后，研究了核DNA复制的抑制情况，这些抗生素对该生物体的叶绿体RNA或蛋白质合成均有已知的作用。每种抗生素在几乎不抑制腺嘌呤掺入叶绿体DNA的药物浓度下，均能抑制核DNA复制。首先，通过高掺入率表明在这些条件下叶绿体DNA正在复制而非仅仅被修复；其次，通过一项（14）N - （15）N密度转移实验表明，在链霉素存在的情况下叶绿体DNA加倍，而未检测到腺嘌呤掺入核DNA。在CsCl梯度中位于核DNA和叶绿体DNA之间的一个小DNA峰（组分III），可能是线粒体DNA峰，在抗生素处理的培养物的DNA中比在对照中更明显。
