Light-dependent changes in plastid differentiation influence carotenoid gene expression and accumulation in carrot roots
Light-dependent changes in plastid differentiation influence carotenoid gene expression and accumulation in carrot roots
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DOI：
10.1007/s11103-012-9893-2
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发表时间：
2012-05-01
影响因子：
5.1
通讯作者：
Stange, Claudia
中科院分区：
文献类型：
--
作者：
Fuentes, Paulina;Pizarro, Lorena;Stange, Claudia
胡萝卜是一种重要的营养作物，因为在二次生长过程中，胡萝卜的储藏根部中积累了高水平的类维生素A胡萝卜素(β-胡萝卜素和较低程度的α-胡萝卜素)。在这项工作中，我们表明，在胡萝卜中，与其他植物的地上器官相反，光通过抑制根的加厚，阻止有色体的分化，最终抑制β-胡萝卜素和α-胡萝卜素生物合成所需的大多数基因的表达，以及次要程度的叶黄素和类胡萝卜素生物合成基因的表达，对根的发育产生深刻的影响。我们观察到在光照或黑暗条件下生长的胡萝卜根段发育过程中类胡萝卜素的分布与基因表达模式的相关性，这表明胡萝卜根发育过程中类胡萝卜素的合成存在转录调控。此外，我们的工作支持了地下贮藏根发育后期，有色体的分化与类胡萝卜素的积累相一致的结论。
Carrot is an important nutritional crop due to the high levels of pro-vitamin A carotenoids (beta-carotene and, to a lower extent, alpha-carotene) that accumulate in its storage root during secondary growth. In this work we show that in carrots, contrary to that reported for aerial organs of other plant species, light has a profound effect on root development by inhibiting root thickening, preventing the differentiation of chromoplasts and eventually repressing the expression of most genes required for the biosynthesis of beta-carotene and alpha-carotene and to a lesser extent genes for xanthophylls and apocarotenoids biosynthesis. We observed a correlation in the carotenoid profile and the patterns of gene expression during the development of root segments grown either in the light or in the dark, which suggests a transcriptional regulation for carotenoid synthesis during carrot root development. Furthermore, our work supports the conclusion that the differentiation of chromoplasts coincides with carotenoid accumulation during the later stages of development of underground storage roots.