PAP2(Production of anthocyanin pigment 2)编码MYB转录因子,与bHLH、WD40形成MYB-bHLH-WD40复合体来调控花青素合成。本研究从埃塞俄比亚芥和黑芥中分别克隆出2个和1个PAP2基因拷贝,分别命名为BcaB.PAP2、BcaC.PAP2、BniB.PAP2,这三...PAP2(Production of anthocyanin pigment 2)编码MYB转录因子,与bHLH、WD40形成MYB-bHLH-WD40复合体来调控花青素合成。本研究从埃塞俄比亚芥和黑芥中分别克隆出2个和1个PAP2基因拷贝,分别命名为BcaB.PAP2、BcaC.PAP2、BniB.PAP2,这三个基因均由3个外显子和2个内含子组成,均编码247个氨基酸。基于本研究克隆的PAP2基因序列和已报道的其他芸薹属PAP2基因序列,设计了3对能分别检测A、B、C基因组PAP2基因的引物,通过等位特异PCR可以区分芸薹属禹氏三角中的6个物种PAP2的基因组来源。选取芥菜型油菜B基因组的BjuB.PAP2基因构建过表达载体,转化拟南芥,其叶片变紫,表明PAP2基因正调控花青素合成。遮光处理10天后紫叶埃塞俄比亚芥的叶片紫色变淡,花青素含量下降了41.22%。荧光定量PCR和转录组研究表明,遮光处理植株叶片中BcaB.PAP2和BcaC.PAP2表达量均下降,花青素合成的结构基因查尔酮合成酶基因(CHS)、查尔酮异构酶基因(CHI)、黄烷酮3-羟化酶基因(F3H)、二氢黄酮醇还原酶基因(DFR)、花青素合成酶基因(ANS)、类黄酮3-葡糖基转移酶基因(UFGT)等基因的表达量也下降。本研究完成了对芸薹属植物中埃塞俄比亚芥和黑芥PAP2基因的克隆,并对其进行进化分析。根据本实验中克隆及其他已报道的PAP2基因序列设计等位基因特异性PCR引物,为芸薹属种间杂交后代PAP2基因的基因组传递鉴定提供了分子标记。通过BjuB.PAP2基因转拟南芥植株结果表明PAP2基因参与花青素的积累。紫叶埃塞俄比亚芥经遮光处理后,发现BcaPAP2基因及花青素合成结构基因的表达受光照的诱导。本研究在芸薹属中克隆PAP2基因,并初步验证PAP2的功能,为进一步解析芸薹属植物花青素合成的调控机制提供参考。展开更多
Anthocyanins confer the wide range of colors for plants and also play beneficial health roles as potentially protective factors against heart disease and cancer. Brassica juncea is cultivated as an edible oil resource...Anthocyanins confer the wide range of colors for plants and also play beneficial health roles as potentially protective factors against heart disease and cancer. Brassica juncea is cultivated as an edible oil resource and vegetable crop worldwide, thus elucidating the anthocyanin biosynthetic pathway would be helpful to improve the nutritional quality of Brassica juncea through the breeding and cultivating of high anthocyanin content varieties. Herein, 129 genes in B. juncea were identified as orthologs of 41 anthocyanin biosynthetic genes(ABGs) in Arabidopsis thaliana by comparative genomic analyses. The B. juncea ABGs have expanded by whole genome triplication and subsequent allopolyploidizatoin, but lost mainly during the whole genome triplication between B. rapa/B. nigra and A. thaliana, rather than the allopolyploidization process between B. juncea and B. rapa/B. nigra, leading to different copy numbers retention of A. thaliana homologous genes. Although the overall expansion levels ABGs were similar to the whole genome, more negative regulatory genes were retained in the anthocyanin biosynthesis regulatory system. Transcriptional analysis of B. juncea with different anthocyanin accumulation showed that BjDFR, BjTT19, BjTT8 are significantly up-regulated in plants with purple leaves as compared with green leaves. The overexpression of BjTT8 and these target genes which were involved in late anthocyanin biosynthesis and transport might account for increasing levels of anthocyanin accumulation in purple leaves. Our results could promote the understanding of the genetic mechanism of anthocyanin biosynthesis in B. juncea.展开更多
文摘PAP2(Production of anthocyanin pigment 2)编码MYB转录因子,与bHLH、WD40形成MYB-bHLH-WD40复合体来调控花青素合成。本研究从埃塞俄比亚芥和黑芥中分别克隆出2个和1个PAP2基因拷贝,分别命名为BcaB.PAP2、BcaC.PAP2、BniB.PAP2,这三个基因均由3个外显子和2个内含子组成,均编码247个氨基酸。基于本研究克隆的PAP2基因序列和已报道的其他芸薹属PAP2基因序列,设计了3对能分别检测A、B、C基因组PAP2基因的引物,通过等位特异PCR可以区分芸薹属禹氏三角中的6个物种PAP2的基因组来源。选取芥菜型油菜B基因组的BjuB.PAP2基因构建过表达载体,转化拟南芥,其叶片变紫,表明PAP2基因正调控花青素合成。遮光处理10天后紫叶埃塞俄比亚芥的叶片紫色变淡,花青素含量下降了41.22%。荧光定量PCR和转录组研究表明,遮光处理植株叶片中BcaB.PAP2和BcaC.PAP2表达量均下降,花青素合成的结构基因查尔酮合成酶基因(CHS)、查尔酮异构酶基因(CHI)、黄烷酮3-羟化酶基因(F3H)、二氢黄酮醇还原酶基因(DFR)、花青素合成酶基因(ANS)、类黄酮3-葡糖基转移酶基因(UFGT)等基因的表达量也下降。本研究完成了对芸薹属植物中埃塞俄比亚芥和黑芥PAP2基因的克隆,并对其进行进化分析。根据本实验中克隆及其他已报道的PAP2基因序列设计等位基因特异性PCR引物,为芸薹属种间杂交后代PAP2基因的基因组传递鉴定提供了分子标记。通过BjuB.PAP2基因转拟南芥植株结果表明PAP2基因参与花青素的积累。紫叶埃塞俄比亚芥经遮光处理后,发现BcaPAP2基因及花青素合成结构基因的表达受光照的诱导。本研究在芸薹属中克隆PAP2基因,并初步验证PAP2的功能,为进一步解析芸薹属植物花青素合成的调控机制提供参考。
基金funded by the National Key Research and Development Program of China(2016YFD0100202)the Natural Science Foundation of Hunan Province,China(2016JJ1010)the Scientific Research Fund of Hunan Provincial Education Department,China(18C0305,17K035,17C0652,and 17C0653)。
文摘Anthocyanins confer the wide range of colors for plants and also play beneficial health roles as potentially protective factors against heart disease and cancer. Brassica juncea is cultivated as an edible oil resource and vegetable crop worldwide, thus elucidating the anthocyanin biosynthetic pathway would be helpful to improve the nutritional quality of Brassica juncea through the breeding and cultivating of high anthocyanin content varieties. Herein, 129 genes in B. juncea were identified as orthologs of 41 anthocyanin biosynthetic genes(ABGs) in Arabidopsis thaliana by comparative genomic analyses. The B. juncea ABGs have expanded by whole genome triplication and subsequent allopolyploidizatoin, but lost mainly during the whole genome triplication between B. rapa/B. nigra and A. thaliana, rather than the allopolyploidization process between B. juncea and B. rapa/B. nigra, leading to different copy numbers retention of A. thaliana homologous genes. Although the overall expansion levels ABGs were similar to the whole genome, more negative regulatory genes were retained in the anthocyanin biosynthesis regulatory system. Transcriptional analysis of B. juncea with different anthocyanin accumulation showed that BjDFR, BjTT19, BjTT8 are significantly up-regulated in plants with purple leaves as compared with green leaves. The overexpression of BjTT8 and these target genes which were involved in late anthocyanin biosynthesis and transport might account for increasing levels of anthocyanin accumulation in purple leaves. Our results could promote the understanding of the genetic mechanism of anthocyanin biosynthesis in B. juncea.
