单 位：
海南大学农学院;中国热带农业科学院热带作物品种资源研究所农业部木薯种质资源保护与利用重点实验室
关键词：
木薯叶片;脱落酸;β-胡萝卜素含量;β-胡萝卜素合成途径;基因表达
摘 要：
探究不同浓度外源ABA对木薯叶片β-胡萝卜素合成途径相关基因的影响。用HPLC测定β-胡萝卜素含量的变化,用q RT-PCR的方法研究木薯胡萝卜素合成途径相关基因的表达水平。喷施20 mg/L外源ABA,木薯叶片β-胡萝卜素含量升高,叶片中涉及类胡萝卜素合成的基因LYCB上调表达,而类胡萝卜素裂解的CCD1基因下调表达。同时,核心酶PSY1与PSY2基因的下调表达与类胡萝卜素含量的变化无关联。而分别采用10 mg/L与80 mg/L浓度喷施后β-胡萝卜素含量均降低,涉及β-胡萝卜素合成通路类胡萝卜素合成相关基因表达水平下降,而经10 mg/L的外源ABA处理催化类胡萝卜素裂解的CCD1基因上调表达。研究表明太低和太高浓度的外源ABA处理木薯叶片导致β-胡萝卜素积累降低,但外源ABA浓度为20 mg/L时能显著提高叶片β-胡萝卜素含量。
译 名：
Effects of Exogenous ABA on the Expression of Genes Associated with β-carotene Synthesis Pathway in Cassava Leaves
作 者：
DENG Changzhe;QIN Yuling;LI Kaimian;CHEN Songbi;College of Agronomy,Hainan University;Tropical Crops Genetic Resources Institute,Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Germplasm Resources Conservation and Utilization of Cassava,Ministry of Agriculture;
关键词：
Cassava leaves;;abscisic acid;;β-carotene content;;β-carotene synthesis pathway;;genes expression
摘 要：
The effects of different concentrations of exogenous ABA on the genes regarding β-carotene biosynthesis pathways on cassava leaves were investigated. HPLC was used to detect the change of β-carotene content, and RT-PCR method was applied to analyze the change of the gene expression regarding β-carotene biosynthetic pathway. Under the treatment with 20 mg/L of exogenous ABA, β-carotene content increased in cassava leaves, in which LYCB gene, associated with carotenoid synthesis, was up-regulated, and CCD1 gene related with carotenoid cleavage was down-regulated. Meanwhile, the down-regulation of core-enzyme genes PSY1 and PSY2 expressions was no correlation with the change of carotenoid content. The treatments with 10 mg/L and 80 mg/L of exogenous ABA, respectively, resulted in the decrease of β-carotene content in cassava leaves. The genes involved in the carotenoid biosynthetic were down-regulated, and CCD1 gene regarding carotenoid cleavage was up-regulated using10 mg/L of exogenous ABA. The results showed that the treatments with too low and too high concentrations of exogenous ABA led to the decrease of β-carotene accumulation, however, using 20 mg/L of exogenous ABA could significantly increase the β-carotene content.
