Ahmed Nasar Uddin, Park Jong-In, Jung Hee-Jeong, Hur Yoonkang, Nou Ill-Sup
Department of Horticulture, Sunchon National University, 413 Jungang-ro, Suncheon, Jeonnam, 540-950, Republic of Korea.
Funct Integr Genomics. 2015 Jul;15(4):383-94. doi: 10.1007/s10142-014-0427-7. Epub 2014 Dec 12.
Flavonoids are divided into several structural classes, including anthocyanins, which provide flower and leaf colors and other derivatives that play diverse roles in plant development and interactions with the environment. This study characterized four anthocyanidin synthase (ANS) genes of Brassica rapa, a structural gene of the anthocyanin biosynthetic pathway, and investigated their association with pigment formation, cold and freezing tolerance in B. rapa. Sequences of these genes were analyzed and compared with similar gene sequences from other species, and a high degree of homology with their respective functions was found. Organ-specific expression analysis revealed that these genes were only expressed in the colored portion of leaves of different lines of B. rapa. Conversely, B. rapa anthocyanidin synthase (BrANS) genes also showed responses to cold and freezing stress treatment in B. rapa. BrANSs were also shown to be regulated by two transcription factors, BrMYB2-2 and BrTT8, contrasting with anthocyanin accumulation and cold stress. Thus, the above results suggest the association of these genes with anthocyanin biosynthesis and cold and freezing stress tolerance and might be useful resources for development of cold-resistant Brassica crops with desirable colors as well.
黄酮类化合物可分为几个结构类别，包括赋予花朵和叶片颜色的花青素，以及在植物发育和与环境相互作用中发挥多种作用的其他衍生物。本研究对芜菁的四个花青素合酶（ANS）基因进行了表征，这是花青素生物合成途径中的一个结构基因，并研究了它们与芜菁色素形成、耐寒性和耐冻性的关系。对这些基因的序列进行了分析，并与其他物种的相似基因序列进行了比较，发现它们与其各自功能具有高度同源性。器官特异性表达分析表明，这些基因仅在不同芜菁品系叶片的有色部分表达。相反，芜菁花青素合酶（BrANS）基因在芜菁中也表现出对低温和冷冻胁迫处理的响应。BrANSs还显示受两个转录因子BrMYB2-2和BrTT8的调控，这与花青素积累和低温胁迫形成对比。因此，上述结果表明这些基因与花青素生物合成以及耐寒性和耐冻性相关，并且可能也是培育具有理想颜色的抗寒芜菁作物的有用资源。
