超表达草生欧文氏菌crtB基因促进转基因番茄类胡萝卜素合成的研究

Overexpression of crtB Gene from Erwinia herbicola Improved Carotenoids Synthesis in Transgenic Tomato

利用重组PCR技术,将草生欧文细菌八氢番茄红素合成酶基因crtB与豌豆质体定位序列ts-rbcS融合,插入质粒载体PMV中,构建了植物表达载体pBI-ts-rbcS-crtB,并通过根瘤农杆菌EHA105介导转化番茄。PCR检测、Southern杂交和RT-PCR分析表明,外源基因crtB已整合到番茄基因组中,并在转基因植株中得到表达。转基因番茄果实中的类胡萝卜素总量增加1.3～2.5倍,八氢番茄红素、番茄红素、β–胡萝卜素和α–胡萝卜素分别增加了4.3、1.8、2.2和2.3倍。转化株系中内源类胡萝卜素合成基因的表达也受到广泛的影响。crtB基因过量表达有效促进了番茄果实中类胡萝卜素的合成和积累。

The fused pea ts-rbcS fragment and crtB gene from Erwinia herbicola was inserted into the PMV plasmid vector,resulting the plant expression vector pBI-ts-rbcS-crtB,which was transformed into tomato by Agrobacterium-mediated transformation.The result of PCR,Southern blot and RT-PCR revealed that foreign crtB gene was integrated and expressed in the transgenic tomato lines.Total carotenoids contents in the fruits of transgenic lines were 1.3–2.5 times higher than that of the control,the phytoene,lycopene,β-carotene and α-carotene contents were 4.3,1.8,2.2,and 2.3 times higer respectively.In addition,the expression of endogenous genes involved in carotenoid synthesis was affected in the transgenic lines.These results suggested that overexpression of crtB significantly enhanced the carotenoids biosynthesis and accumulation in transgenic tomato fruits.