The role of carotenoid cleavage dioxygenases in the regulation of carotenoid profiles during maturation in citrus fruit
The role of carotenoid cleavage dioxygenases in the regulation of carotenoid profiles during maturation in citrus fruit
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DOI：
10.1093/jxb/erj172
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发表时间：
2006-01-01
影响因子：
6.9
通讯作者：
Yano, Masamichi
中科院分区：
文献类型：
--
作者：
Kato, Masaya;Matsumoto, Hikaru;Yano, Masamichi
为了研究类胡萝卜素谱与类胡萝卜素裂解双加氧酶基因表达之间的关系，以3个汁囊中9-顺式紫黄质含量不同的柑橘品种，温州蜜柑（Citrus unshiu Marc.;积累低水平9-顺式-紫黄质的品种）、瓦伦西亚橙子（Citrus sinensis Osbeck;积累高水平9-顺式-紫黄质的品种）和里斯本柠檬（Citrus利蒙Burm.f.;积累了不可检测水平的9-顺式紫黄质的品种）。克隆了三个cDNA（CitCCD 1、CitNCED 2和CitNCED 3）。重组CitCCD 1蛋白在9-10和9 '-10'位置切割β-隐黄质、玉米黄质和全反式紫黄质，在9 '-10'位置切割9-顺式紫黄质。重组CitNCED 2和CitNCED 3蛋白在11-12位切割9-顺式紫黄质以形成脱落酸（阿坝）的前体黄嘌呤（xanthoxin）。CitCCD 1基因在3个品种果实成熟过程中的外果皮和汁囊中表达量增加。在温州蜜柑中，CitNCED 2和CitNCED 3的基因表达显著增加，伴随着大量的阿坝积累在果皮和汁囊中。在瓦伦西亚橙子中，CitNCED 3的基因表达随着果皮中阿坝水平的轻微升高而增加，而CitNCED 2的基因表达和阿坝水平在汁囊中均未显著增加。在里斯本柠檬中，CitNCED 2的基因表达显着增加，伴随着外果皮和汁囊中阿坝水平的增加。这些结果表明，在汁囊中，阿坝合成的高效裂解反应降低了温州蜜柑和里斯本柠檬中的9-顺式紫黄质水平，而低裂解反应保持了瓦伦西亚橙子中主要的9-顺式紫黄质积累。
To investigate the relationship between a carotenoid profile and gene expression for carotenoid cleavage dioxygenases, three citrus varieties that exhibit different 9-cis-violaxanthin levels in their juice sacs, Satsuma mandarin (Citrus unshiu Marc.; a variety accumulating a low level of 9-cis-violaxanthin), Valencia orange (Citrus sinensis Osbeck; variety accumulating a high level of 9-cis-violaxanthin), and Lisbon lemon (Citrus limon Burm.f.; a variety accumulating an undetectable level of 9-cis-violaxanthin) were used. Three cDNAs (CitCCD1, CitNCED2, and CitNCED3) were cloned. The recombinant CitCCD1 protein cleaved beta-cryptoxanthin, zeaxanthin, and all-trans-violaxanthin at the 9-10 and 9'-10' positions and 9-cis-violaxanthin at the 9'-10' position. The recombinant CitNCED2 and CitNCED3 proteins cleaved 9-cis-violaxanthin at the 11-12 position to form xanthoxin, a precursor of abscisic acid (ABA). The gene expression of CitCCD1 increased in the flavedos and juice sacs of the three varieties during maturation. In Satsuma mandarin, the gene expression of CitNCED2 and CitNCED3 increased noticeably, accompanying a massive accumulation of ABA in the flavedo and juice sacs. In Valencia orange, the gene expression of CitNCED3 increased with a slight elevation of the ABA level in the flavedo, whereas neither the gene expression of CitNCED2 nor the ABA level increased noticeably in the juice sacs. In Lisbon lemon, the gene expression of CitNCED2 increased remarkably, accompanying increases in the ABA level in the flavedo and juice sacs. These results suggest that, in the juice sacs, the efficient cleavage reaction for ABA synthesis reduces the 9-cis-violaxanthin level in Satsuma mandarin and Lisbon lemon, whereas the low cleavage reaction maintains the predominant 9-cis-violaxanthin accumulation in Valencia orange.