摘要 : 2017年7月26日,国际顶尖学术期刊《Science》旗下《Science Advances》杂志上在线发表了日本农业和食品产业技术综合研究机构野田尚信等人利用转基因技术第一次在世界上培育出一种“真正蓝色”的菊花。
2017年7月26日,国际顶尖学术期刊《Science》旗下《Science Advances》杂志上在线发表了日本农业和食品产业技术综合研究机构野田尚信等人利用转基因技术第一次在世界上培育出一种“真正蓝色”的菊花。
蓝色花卉给人高贵、冷艳的感觉,但人们常见的观赏花卉却少见蓝色。自然界中的天然蓝色花卉通常产生被称为花翠素的蓝色色素。但此前研究发现,利用人工方法让常见观赏花卉含有花翠素,培育出的不是蓝色花,而是紫色或紫罗兰色花。
野田尚信等人此次的新方法涉及两种基因。首先,他们把蓝色风铃草的一种基因“插”入菊花,修改花翠素让花朵呈紫色;然后,他们“插”入来自蝶豆花的第二种基因,这种基因给花翠素增加了一种糖分子,结果菊花就变成了“真正的蓝色”。
“这是此前从未报告过的发现,”研究人员在论文中写道,“这种简单方法是培育各种观赏植物开蓝色花的一种很有前景的途径。”
原文链接:
Generation of blue chrysanthemums by anthocyanin B-ring hydroxylation and glucosylation and its coloration mechanism
原文摘要:
Various colored cultivars of ornamental flowers have been bred by hybridization and mutation breeding; however, the generation of blue flowers for major cut flower plants, such as roses, chrysanthemums, and carnations, has not been achieved by conventional breeding or genetic engineering. Most blue-hued flowers contain delphinidin-based anthocyanins; therefore, delphinidin-producing carnation, rose, and chrysanthemum flowers have been generated by overexpression of the gene encoding flavonoid 3′,5′-hydroxylase (F3′5′H), the key enzyme for delphinidin biosynthesis. Even so, the flowers are purple/violet rather than blue. To generate true blue flowers, blue pigments, such as polyacylated anthocyanins and metal complexes, must be introduced by metabolic engineering; however, introducing and controlling multiple transgenes in plants are complicated processes. We succeeded in generating blue chrysanthemum flowers by introduction of butterfly pea UDP (uridine diphosphate)–glucose:anthocyanin 3′,5′-O-glucosyltransferase gene, in addition to the expression of the Canterbury bells F3′5′H. Newly synthesized 3′,5′-diglucosylated delphinidin-based anthocyanins exhibited a violet color under the weakly acidic pH conditions of flower petal juice and showed a blue color only through intermolecular association, termed “copigmentation,” with flavone glucosides in planta. Thus, we achieved the development of blue color by a two-step modification of the anthocyanin structure. This simple method is a promising approach to generate blue flowers in various ornamental plants by metabolic engineering.