An evolutionary view of plant tissue culture: somaclonal variation and selection
An evolutionary view of plant tissue culture: somaclonal variation and selection
复制标题
植物组织培养的进化观点：体细胞克隆变异和选择
DOI：
10.1007/s00299-012-1281-5
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发表时间：
2012-09-01
影响因子：
6.2
通讯作者：
Wang, Li
中科院分区：
文献类型：
--
作者：
Wang, Qin-Mei;Wang, Li
从离体培养物再生的植物具有一系列遗传和表观遗传变化。这种现象被称为“体细胞克隆变异”，体细胞克隆变异（SV）的频率通常远远超出自然界的预期。最初，发现培养时间和检测到的SV之间的关系支持SV随培养时间积累的普遍看法。然而，一些研究表明，旧的文化产生的再生少SV。是什么导致了这种看似矛盾的现象？本文提出了一种新的愈伤组织离体选择假说--分化瓶颈（D-bottleneck）和去分化瓶颈（Dd-bottleneck），认为自然选择理论适用于离体细胞群体。随着离体培养时间的延长，愈伤组织或再生体中SV频率的增加或减少取决于真型细胞与有害细胞之间的增殖竞争结果，本文讨论了用进化理论解释与时间相关的SV复杂情况的可能性。此外，还提出了SV阈值、空间决定假说和D瓶颈来解释植物组织培养过程中再生能力的丧失。
Plants regenerated from in vitro cultures possess an array of genetic and epigenetic changes. This phenomenon is known as 'somaclonal variation' and the frequency of somaclonal variation (SV) is usually elevated far beyond that expected in nature. Initially, the relationship between time in culture and detected SV was found to support the widespread belief that SV accumulates with culture age. However, a few studies indicated that older cultures yielded regenerants with less SV. What leads to this seemed contradiction? In this article, we have proposed a novel in vitro callus selection hypothesis, differentiation bottleneck (D-bottleneck) and dedifferentiation bottleneck (Dd-bottleneck), which consider natural selection theory to be fit for cell population in vitro. The results of multiplication races between the cells with the true-to-type phenotype and the deleterious cells determine the increase/decrease of SV frequencies in calli or regenerants as in vitro culture time goes on. The possibility of interpreting the complex situation of time-related SV by the evolutionary theory is discussed in this paper. In addition, the SV threshold, space-determined hypothesis and D-bottleneck are proposed to interpret the loss of the regenerability through a long period of plant tissue culture (PTC).