Microspore-derived embryogenesis in pepper (Capsicum annuum L.):: subcellular rearrangements through development
Microspore-derived embryogenesis in pepper (Capsicum annuum L.):: subcellular rearrangements through development
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DOI：
10.1042/bc20040142
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发表时间：
2005-09-01
影响因子：
2.7
通讯作者：
Testillano, PS
中科院分区：
文献类型：
--
作者：
Bárány, I;González-Melendi, P;Testillano, PS
背景信息。体外培养的小孢子经过适当的应激处理后，可以转向胚胎发生途径。这个过程被称为小孢子胚胎发生，是植物育种的重要工具。对经济上有意义的作物，特别是顽固植物中这一过程的基础研究非常有限，并且对事件的顺序知之甚少。原位研究对于小孢子胚胎发生的适当剖析非常方便，小孢子胚胎发生是不同细胞群（诱导和非诱导）的混合物异步发育的过程。结果。在本研究中，研究了辣椒（一种具有农艺价值的园艺作物）早期小孢子胚胎发生过程中特定亚细胞重排的发生与增殖和分化事件的关系。 Capsicum annuum L.（变种 Yolo Wonder B）的单倍体植物已通过在 35 摄氏度下热处理 8 天从体外花药培养物再生。使用低温处理、保存完好的标本，在光学和电子显微镜水平上分析了小孢子衍生胚胎的形态发生。与正常配子体发育的比较揭示了胚胎发生诱导后细胞组织的变化，并允许表征与增殖活性和分化的激活相关的一组结构事件的时间顺序，这些事件以前在辣椒中没有定义。这些变化主要影响质体、液泡室、细胞壁和细胞核。进一步的分化过程模仿了合子发育的过程。结论。所报告的变化可以被认为是小孢子胚胎发生的标志。他们增加了对控制小孢子胚胎发生的转换和进展的机制的理解，这可能有助于提高其效率并指导策略，特别是在农艺学上感兴趣的作物中。
Background information. In vitro-cultured microspores, after an appropriate stress treatment, can switch towards an embryogenic pathway. This process, known as microspore embryogenesis, is an important tool in plant breeding. Basic studies on this process in economically interesting crops, especially in recalcitrant plants, are very limited and the sequence of events is poorly understood. In situ studies are very convenient for an appropriate dissection of microspore embryogenesis, a process in which a mixture of different cell populations (induced and non-induced) develop asynchronically.Results. In the present study, the occurrence of defined subcellular rearrangements has been investigated during early microspore embryogenesis in pepper, an horticultural crop of agronomic interest, in relation to proliferation and differentiation events. Haploid plants of Capsicum annuum L. (var. Yolo Wonder B) have been regenerated from in vitro anther cultures by a heat treatment at 35 degrees C for 8 days. Morphogenesis of microspore-derived embryos has been analysed, at both light and electron microscopy levels, using low-temperature-processed, well-preserved specimens. The comparison with the normal gametophytic development revealed changes in cell organization after embryogenesis induction, and permitted the characterization of the time sequence of a set of structural events, not previously defined in pepper, related to the activation of proliferative activity and differentiation. These changes mainly affected the plastids, the vacuolar compartment, the cell wall and the nucleus. Further differentiation processes mimicked that of the zygotic development.Conclusions. The reported changes can be considered as markers of the microspore embryogenesis. They have increased the understanding of the mechanisms controlling the switch and progression of the microspore embryogenesis, which could help to improve its efficiency and to direct strategies, especially in agronomically interesting crops.