摘要
利用生物信息鉴定百子莲MYB家族成员,挖掘并验证了调控百子莲蓝色花色形成的关键基因。以全长转录组测序数据作为参考序列,鉴定得到百子莲123个MYB家族成员,包括60个R2R3-MYB、4个3R-MYB、2个4R-MYB和57个1R-MYB基因。对调控类黄酮生物合成的主要亚家族R2R3-MYB进行分析发现,R2-和R3-repeats的序列较为保守,根据系统进化关系分为22个亚组(A1~A22)。特殊的是,相较拟南芥的25个亚组,百子莲缺乏正向调控花色素苷合成的典型亚组S6。与花色形成相关的其他亚组有A18、A17和A16,其成员ApMYB4、ApMYB6、ApMYB7、ApMYB12和ApMYB111定位于细胞核,ApMYB123集中分布于核仁中。在蓝色百子莲花瓣着色过程中,ApMYB12显著上调表达,而ApMYB111显著下调表达。ApMYB4、ApMYB6和ApMYB7在蓝花各发育阶段的表达量均低于白花,预示这些基因可能是百子莲蓝色形成的负调控因子。ApMYB123在白花的开放前期大量表达,说明该基因可能在此阶段促进花瓣合成原花青素。在烟草中过表达ApMYB12,烟草花瓣颜色较野生型变浅,花色素苷含量减少54.55%~62.50%,而黄酮醇含量提高125%~170%,证实ApMYB12调控辅助色素黄酮醇的生物合成,从而影响蓝色的形成。
MYB gene family members of Agapanthus praecox were identified by bioinformatics methods and the function of key genes that regulate blue flower coloration was verified.In total,123 ApMYBs were identified based on full-length transcriptome sequencing data,including 60 R2R3-MYBs,four 3R-MYBs,two 4R-MYBs and 571R-MYBs.Then,the R2R3-MYBs that regulate flavonoid biosynthesis were further analyzed.R2R3-MYBs were divided into 22 subgroups(A1-A22),together with A18(S4),A17(S5)and A16(S7)subgroups were all related to flower coloration,except for S6 subgroup.ApMYB4,ApMYB6,ApMYB7,ApMYB12,ApMYB111 and ApMYB123 were all localized in the nuclei.Whereas,ApMYB123 was especially concentrated in the nucleolus.During blue flower coloration,ApMYB12 was significantly up-regulated,while ApMYB111 was opposite.White flowers showed increased expression of ApMYB4,ApMYB6 and ApMYB7 compared to blue flowers,indicating them as the negative regulators of coloration.A specific expression peak of ApMYB123 was arisen in bloom stage of white flowers,suggesting biosynthesis of proanthocyanidins.Further ectopic expression of ApMYB12 in tobacco found that the petal color turned lighter than wild type plants.In addition,the anthocyanin content reduced by 54.55%-62.50%while the flavonols content increased by 125%-170%.These results demonstrated that ApMYB12 regulated the biosynthesis of auxiliary pigment flavonols,thereby regulating the coloration of blue flower.
作者
贺威智
雷伟奇
郭祥鑫
李蕊莲
陈冠群
HE Weizhi;LEI Weiqi;GUO Xiangxin;LI Ruilian;CHEN Guanqun(Department of Landscape Architecture,School of Design,Shanghai Jiao Tong University,Shanghai 200240,China;School of Agriculture and Biology,Shanghai Jiao Tong University,Shanghai 200240,China;Shanghai Administration Affairs Center of Parks,Shanghai 200023,China)
出处
《园艺学报》
CAS
CSCD
北大核心
2023年第6期1255-1268,共14页
Acta Horticulturae Sinica
基金
上海市自然科学基金项目(22ZR1428600)
国家自然科学基金项目(31901351)
上海市科技创新行动计划农业科技领域项目(22N11900500)。
关键词
百子莲
转录因子
MYB家族
蓝色花形成
黄酮醇
Agapanthus praecox
transcription factor
MYB gene family
blue flower coloration
flavonol
