Plant Breeding Institute, CB2 2LQ, Trumpington, Cambridge, U.K..
Plant Mol Biol. 1985 Jul;4(4):233-40. doi: 10.1007/BF02418241.
The amounts of a 1.9 kb mitochondrial plasmid relative to sequences in another mitochondrial DNA replicon and also to nuclear ribosomal DNA sequences have been compared in maize leaves and anthers. Similar comparisons have been made between plants with the same nuclear genotype but containing normal, S, or T cytoplasms. The ratio of 1.9 kb plasmid to nuclear rDNA is lower in plants with normal cytoplasm than in plants with S or T cytoplasm. It also differs between leaves and anthers. Furthermore, the relative concentration of the mitochondrial DNA sequences belonging to different replicons differs between leaves and anthers. It is concluded that components of different mitochondrial replicons are not maintained in fixed ratios during development and that the concentration of the 1.9 kb plasmid is regulated, in part, by cytoplasmically-inherited determinants. The 1.9 kb plasmid is absent from lines with the Vg cytoplasm, but related sequences are found in the maize nuclear genome.
已比较了玉米叶片和花粉中 1.9kb 线粒体质体与另一个线粒体 DNA 复制子以及核核糖体 DNA 序列的含量。在具有相同核基因型但含有正常、S 或 T 细胞质的植物之间也进行了类似的比较。具有正常细胞质的植物中 1.9kb 质粒与核 rDNA 的比值低于 S 或 T 细胞质的植物。它在叶片和花粉之间也有所不同。此外，属于不同复制子的线粒体 DNA 序列的相对浓度在叶片和花粉之间也不同。因此得出结论，不同线粒体复制子的组成成分在发育过程中不能保持固定比例，并且 1.9kb 质粒的浓度部分受到细胞质遗传决定因素的调节。具有 Vg 细胞质的系中不存在 1.9kb 质粒，但在玉米核基因组中发现了相关序列。
