摘要
以不结球白菜紫色品系NJZX1-3和其绿色突变体NJZX1-0及其后代F_2的2个株系NJZX2-1和NJZX2-2为材料,研究花色苷合酶基因在紫色不结球白菜叶片花色苷合成途径中的作用。利用同源克隆的方法,分别在NJZX1-3及NJZX1-0中克隆到花色苷合酶基因;经序列比对发现,花色苷合酶基因的核苷酸和氨基酸序列在2种材料和大白菜中完全一致,长度为1077 bp,编码358个残基,第211~第307肽段具有2OG-Fe(Ⅱ)双加氧酶家族基因的结构域,被命名为BrcANS。BrcANS蛋白与同科芥菜的同源性高达99%,进化关系亦与其最相近。在全部4种材料鲜叶中,总花色苷的含量(TAC)与叶片紫色程度是一致的,其中,NJZX1-3叶片中总花色苷含量最高,达到80.15±5.74 mg 100g^(–1) FW;BrcANS表达量为NJZX1-0<NJZX2-1<NJZX2-2<NJZX1-3,与其总花色苷含量呈正相关。BrcANS的mRNA在NJZX1-3和NJZX1-0两种材料的不同组织中特异性表达:在叶片中高度表达,而在其他组织中表达较弱;另外,在两种材料间的表达亦存在显著差异,在NJZX1-3叶片中的表达丰度显著高于NJZX1-0。随着叶龄的增大,紫色不接球白菜叶片紫色变浅,BrcANS的表达量下降,且在NJZX1-3和NJZX1-0间的表达差异亦明显减小。以上结果表明,BrcANS基因是紫色不结球白菜中花色苷合成的关键基因之一,其mRNA表达量与叶片紫色直接相关,可能在其转录水平上调控叶片中紫色的形成。
Purple non-heading Chinese cabbage cultivar NJZX1-3, its green leaf mutant line NJZX1-0, and their progeny F_2： NJZX2-1 and NJZX2-2 were used to study the function of anthocyanidin synthase gene in the anthocyanin biosynthesis of non-heading Chinese cabbage leaf. Homology-based cloning was used and anthocyanidin synthase gene was respectively cloned from two cultivars（NJZX1-3 and NJZX1-0）. The gene nucleotides and amino acids sequences found in the two materials and Chinese cabbage were exactly the same, with a length of 1077 bp and encoding a peptide with 358 residues. Furthermore, a 2OG-Fe（Ⅱ） dioxygenase super family domain was found in the amino acid sequence from the 211 th to the 307 th amino acids and the gene was named as BrcANS. The homology between BrcANS protein and Bj ANS protein was up to 99%, in accordance with the close relationship between them. Their total anthocyanin content（TAC） was consistent with the degree of purple in fresh leaves of the four materials, of which total anthocyanin content in cultivar NJZX1-3 leaves was the highest, up to 80.15±5.74 mg 100 g^（–1） FW. Simultaneously, the expression level of BrcANS（NJZX1-0 〈NJZX2-1 〈NJZX2-2 〈NJZX1-3） was positively correlated with the increasing trend of TAC. The mRNA of BrcANS exhibited tissue-specific expression in both materials, showing high level in leaves and lower level in other organs. In addition, the expression of two materials was significantly different, indicating that the expression of BrcANS in cultivar NJZX1-3 leaves was obviously higher than that in mutant line NJZX1-0. With the in-creasing of leaf age, the leaf color became shallow and the expression of BrcANS reduced. Meanwhile, the difference of expression between NJZX1-3 and NJZX1-0 decreased significantly. These results indicated that BrcANS gene is one of the key genes in the anthocyanin biosynthesis of non-heading Chinese cabbage leaf, and its expression level is directly related to the purple color of leaves, thus the gene might regulate the formation of the purple color in leaves at transcriptional level.
出处
《作物学报》
CAS
CSCD
北大核心
2016年第6期850-859,共10页
Acta Agronomica Sinica
基金
江苏省农业科技自主创新项目[CX(15)1015]
江苏省科技支撑计划项目(BE2013429)资助~~
关键词
不结球白菜
花色苷合酶
同源克隆
序列分析
总花色苷含量
基因表达
Non-heading Chinese cabbage
Anthocyanidin synthase
Homology-based cloning
Sequence analysis
Total anthocyanin content
Gene expression
