Molecular Cloning and Expression of Carotenogenic Genes in Yellowish and Mutant Whitish Loquat (Eriobotrya japonica) Fruits  

枇杷黄肉和白肉突变体类胡萝卜素基因的克隆和表达分析(英文)

作　　者：孙淑霞[1] 谢红江[1] 陈栋[1] 李靖[1] 涂美艳[1] 江国良[1] 

机构地区：[1]四川省农业科学院园艺研究所/农业部西南地区园艺作物生物学与种质创制重点实验室,四川成都610066

出　　处：《Agricultural Science & Technology》2013年第7期941-945,共5页农业科学与技术（英文版）

基　　金：Supported by Special Fund for Agro-scientific Research in the Public Interest of China(201003073);Key Laboratory Program of Agriculture Ministry of China(2013JCYJ-004);Applied Basic Research Program of Chengdu City Science and Technology Bureau(11DXYB039NC);Youth Foundation of Sichuan Province(2011QNJJ-010)~~

摘　　要：ObjectiveThe study aimed to explore the factors regulating carotenoid accumulation in flesh color. MethodA loquat mutation （red-or orange-fleshed plant emerged a bud mutation of white-flesh in trunk） was used as material; HPLC analysis of β-carotene content was conducted. ResultThe β-carotene concentration in the flesh of wild and mutant types was 60.9 and 4.6 μg/g fresh weight, respectively. According to the conserved regions of genes from rose family genome, carotenogenic gene fragments in wild and mutant types were obtained. No nucleotide variation of the carotenogenic gene fragments was observed between wild and mutant genome. Real-time quantitative polymerase chain reaction （Q-PCR） was compared and one carotenogenic gene, β-ring hydroxylase （HYB） were considerably suppressed in mature mutant loquat fruits compared with that in wild. The other six carotenogenic genes were also expressed but the expression patterns appeared to be not correlated with the amount of β-carotene concentration in wild loquat flesh. ConclusionThe mutant whitish loquat lacks the ability to synthesize β-carotene because of the transcriptional down-regulation of carotenogenic gene HYB.[目的]探索黄肉枇杷果实类胡萝卜积累的调控机制。[方法]该研究以枇杷突变体(黄肉枇杷一枝芽变结出白肉果实)为供试材料,利用高效液相色谱测定成熟果肉中β-胡萝卜素的积累,对野生型和突变型枇杷类胡萝卜素合成途径基因进行同源克隆及表达分析。[结果]野生型黄肉和突变体白肉枇杷成熟果肉中β-胡萝卜素含量分别为60.9和4.6μg/g;利用同源克隆获得的5个枇杷类胡萝卜素合成基因编码区序列在野生型和突变型没有发现核苷酸变异;实时荧光定量PCR分析显示类胡萝卜素β环羟化酶基因在突变体白肉果实中的表达显著降低,其它6个类胡萝卜素合成途径基因在两供试材料中的表达水平没有差异,与β-胡萝卜素的积累没有直接关联。[结论]突变体白肉枇杷缺少β-胡萝卜素的积累可能与类胡萝卜素β环羟化酶基因表达量下调有关。

关 键 词：Β-CAROTENE β-ring hydroxylase Flesh colour Gene expression LOQUAT 

分 类 号：S667.3[农业科学—果树学]