The ABA1 gene and carotenoid biosynthesis are required for late skotomorphogenic growth in Arabidopsis thaliana
The ABA1 gene and carotenoid biosynthesis are required for late skotomorphogenic growth in Arabidopsis thaliana
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DOI：
10.1111/j.1365-3040.2007.01759.x
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发表时间：
2008-02-01
影响因子：
7.3
通讯作者：
Micol, Jose Luis
中科院分区：
文献类型：
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作者：
Barrero, Jose Maria;Rodriguez, Pedro L.;Micol, Jose Luis
几种植物激素，包括生长素、油菜素类固醇和赤霉素，是种子形态发生所必需的，种子形态发生是幼苗在没有光的情况下经历的黄化生长。为了研究脱落酸（阿坝）缺陷突变体在黑暗中的生长，我们分析了几个aba 1功能丧失的等位基因，这是缺乏玉米黄质环氧酶。aba 1突变体表现出部分去黄化的表型，包括减少下胚轴生长，子叶扩展和真叶的发展，在后期skotomorphogenic增长。与此相反，只有小的差异下胚轴生长被发现之间的野生型幼苗和ABA-缺陷的突变体受损的后续步骤的途径，即nced 3，aba 2，aba 3和aao 3。有趣的是，当野生型幼苗在补充有氟啶酮（八氢番茄红素去饱和酶抑制剂，因此也是类胡萝卜素生物合成的抑制剂）的培养基上黑暗生长时，获得了aba 1突变体部分去黄化表型的表型。阿坝补充没有恢复正常skotomorphogenic生长的aba 1突变体或氟立酮处理的野生型植物，表明氟立酮类胡萝卜素生物合成的直接抑制作用。此外，aba 1突变体表现出受损的β-胡萝卜素衍生的叶黄素，新黄质，紫黄质和花药黄质的生产。由于氟啶酮治疗野生型植物phenocopied暗生长的aba 1突变体的表型，受损的类胡萝卜素的生物合成在aba 1突变体可能是负责观察skotomorphogenic表型。因此，ABA 1是skotomorphogenic生长所必需的，β-胡萝卜素衍生的叶黄素是skotomorphogenesis的假定调节剂。
Several plant hormones, including auxin, brassinosteroids and gibberellins, are required for skotomorphogenesis, which is the etiolated growth that seedlings undergo in the absence of light. To examine the growth of abscisic acid (ABA)-deficient mutants in the dark, we analysed several aba1 loss-of-function alleles, which are deficient in zeaxanthin epoxidase. The aba1 mutants displayed a partially de-etiolated phenotype, including reduced hypocotyl growth, cotyledon expansion and the development of true leaves, during late skotomorphogenic growth. In contrast, only small differences in hypocotyl growth were found between wild-type seedlings and ABA-deficient mutants impaired in subsequent steps of the pathway, namely nced3, aba2, aba3 and aao3. Interestingly, phenocopies of the partially de-etiolated phenotype of the aba1 mutants were obtained when wild-type seedlings were dark-grown on medium supplemented with fluridone, an inhibitor of phytoene desaturase, and hence, of carotenoid biosynthesis. ABA supplementation did not restore the normal skotomorphogenic growth of aba1 mutants or fluridone-treated wild-type plants, suggesting a direct inhibitory effect of fluridone on carotenoid biosynthesis. In addition, aba1 mutants showed impaired production of the beta-carotene-derived xanthophylls, neoxanthin, violaxanthin and antheraxanthin. Because fluridone treatment of wild-type plants phenocopied the phenotype of dark-grown aba1 mutants, impaired carotenoid biosynthesis in aba1 mutants is probably responsible for the observed skotomorphogenic phenotype. Thus, ABA1 is required for skotomorphogenic growth, and beta-carotene-derived xanthophylls are putative regulators of skotomorphogenesis.