Department of Biology, University of York, York Y01 5DD, United Kingdom.
Plant Physiol. 1982 Jun;69(6):1387-91. doi: 10.1104/pp.69.6.1387.
Plastids at different stages of development were isolated from light-grown wheat (Triticum aestivum, var. Maris Dove) seedling leaves, and the average chloroplast DNA (cpDNA) per plastid at each developmental stage was measured directly. In the earliest stages of development, the number of plastids per cell and the amount of cpDNA per cell increased with cell age, but cpDNA per plastid remained constant at between 800 and 1,000 genome copies per plastid. After this phase, plastids per cell continued to increase, but cpDNA per plastid decreased. Subsequently, both plastids per cell and cpDNA per plastid remained constant as cell age increased, the final DNA content being approximately 300 genome copies per plastid. These results are related to previous reports of cpDNA changes during the development of dicotyledonous plants, and to theories about the regulation of chloroplast numbers per cell.
从光培养的小麦（Triticum aestivum，var. Maris Dove）幼苗叶片中分离出处于不同发育阶段的质体，并直接测量每个发育阶段每个质体的平均叶绿体 DNA（cpDNA）。在发育的最早阶段，每个细胞中的质体数量和每个细胞中的 cpDNA 量随着细胞年龄的增加而增加，但每个质体中的 cpDNA 保持不变，每个质体中有 800 到 1000 个基因组拷贝。在此阶段之后，每个细胞中的质体数量继续增加，但每个质体中的 cpDNA 减少。随后，随着细胞年龄的增加，每个细胞中的质体数量和每个质体中的 cpDNA 数量保持不变，最终每个质体中的 DNA 含量约为 300 个基因组拷贝。这些结果与以前关于双子叶植物发育过程中 cpDNA 变化的报告以及关于每个细胞中叶绿体数量调节的理论有关。
