Studies on the mode of separation of chloroplast genomes in parasexual hybrid calli
Studies on the mode of separation of chloroplast genomes in parasexual hybrid calli
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拟性杂种愈伤组织叶绿体基因组分离模式的研究
DOI：
10.1266/jjg.61.437
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发表时间：
1986
期刊：
影响因子：
--
通讯作者：
A. Hirai
中科院分区：
文献类型：
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作者：
S. Akada;A. Hirai
在青花烟草和朗斯多夫烟草之间的准有性杂种愈伤组织中，两种亲本类型的叶绿体在愈伤组织发育过程中分离。研究分离模式的系统涉及 N. glauca 和 N. langsdorfii 之间的杂交愈伤组织的激素独立生长作为性旁杂种的选择标记，以及 Fraction I 蛋白大亚基 (LS) 的等电聚焦模式作为叶绿体遗传标记。我们通过利用戈赛猪笼草作为叶绿体供体改进了该系统，因为来自戈赛猪笼草和兰斯多夫猪笼草的LS的等电聚焦模式可以清楚地区分。通过有性杂交将青绿猪笼草的核基因组转入戈赛猪笼草，恢复了适合在小愈伤组织状态下选择杂种的激素独立性。使用改进的系统，对叶绿体分离模式进行了更详细的研究。研究发现，两个月大的准有性杂交愈伤组织中 84% 的细胞仅具有一种或另一种亲本类型的叶绿体，16% 的细胞具有两种类型。我们基于两种类型的叶绿体通过愈伤组织中的细胞分裂随机分离的假设，使用公式计算了分离率。计算得到的结果与两个月龄副性杂种愈伤组织分析得到的实验数据一致，说明我们的假设是合理的。
In the parasexual hybrid callus between Nicotiana glauca and N. langsdorfii, the two parental types of chloroplasts separate during callus development. The system to investigate the mode of separation involves the hormone independent growth of the hybrid callus between N. glauca and N. langsdorfii as a selective marker for the parasexal hybrid and the isoelectrofocusing patterns of the large subunit (LS) of Fraction I protein as a chloroplast genetic marker. We improved this system by utilizing N. gossei as a chloroplast donor, because the isoelectrofocusing patterns of LS from N. gossei and that from N. langsdorfii can be distinguished clearly. The hormone independency which is suitable for selecting hybrids in the state of small calli was restored by transmitting the nuclear genome of N. glauca into N. gossei by means of sexual hybridization. Using the improved system, the mode of chloroplast separation was investigated in more detail. It was found that 84% of the cells in a two month old parasexual hybrid callus have only one or the other parental type of chloroplasts and 16% of the cells have two types.We calculated the rate of separation using the formulae based on the assumption that the two types of chloroplasts separate at random by cell divisions in the callus. The result obtained by the calculation turned out to be consistent to the experimental data obtained by the analysis of the two month old parasexual hybrid callus, showing that our assumption is reasonable.