桂花OfMYB1R47转录因子在芳香挥发物形成过程中的功能分析  

Functional analysis of OfMYB1R47 transcription factor in Osmanthus fragrans during the formation of aromatic volatiles

作　　者：岳远征[1,2] 胡宏敏 刘家伟 申慧敏 施婷婷[1,2] 杨秀莲[1,2] 王良桂[1,2] YUE Yuanzheng;HU Hongmin;LIU Jiawei;SHEN Huimin;SHI Tingting;YANG Xiulian;WANG Lianggui(College of Landscape Architecture,Nanjing Forestry University,Nanjing 210037,Jiangsu,China;Jiangsu Key Laboratory of Landscape Architecture,Nanjing Forestry University,Nanjing 210037,Jiangsu,China)

机构地区：[1]南京林业大学风景园林学院,江苏南京210037 [2]南京林业大学江苏省风景园林重点实验室,江苏南京210037

出　　处：《浙江农林大学学报》2023年第3期465-474,共10页Journal of Zhejiang A&F University

基　　金：国家自然科学基金资助项目(32071828,31870695);江苏高校优势学科建设工程资助项目。

摘　　要：【目的】花香是桂花Osmanthus fragrans最重要的观赏性状之一,对桂花MYB-related基因家族成员OfMYB1R47在芳香挥发物形成过程中的功能进行鉴定,可为桂花花香合成的转录调控机制研究提供新的基因节点。【方法】以桂花‘日香桂’O. fragans ‘Rixianggui’和本氏烟草Nicotiana benthamiana为材料,以前期的花香转录组数据筛选出的MYB-related家族基因OfMYB1R47为目标基因。通过基因序列和系统进化树、实时荧光定量PCR (RTqPCR)、亚细胞定位、酵母自激活、瞬时超量表达本氏烟草以及气相色谱-质谱联用(GC-MS)测定挥发性代谢物质量分数,对OfMYB1R47基因的特性和功能进行分析。【结果】OfMYB1R47基因开放阅读框长度为1 485 bp,共编码494个氨基酸。系统进化树表明:与OfMYB1R47同源性最高的基因在木犀科Oleaceae的木樨榄Olea europaea subsp.europaea中;RT-qPCR分析发现:OfMYB1R47基因的表达量随着桂花花香的释放呈现先上升后下降的趋势,且在桂花花朵初花期表达量最高;亚细胞定位和酵母自激活实验表明:OfMYB1R47主要定位在细胞核,且具有自激活活性;与转化空载体的植株相比,在瞬时超量表达该基因的本氏烟草叶片中,辛醛、β-紫罗兰酮等芳香挥发性物质量分数均发生了明显改变。【结论】OfMYB1R47具有典型的转录因子特征,其表达模式与桂花花香的释放具有一定的关联性,参与调控了桂花β-紫罗兰酮等花香物质的合成,可作为桂花花香分子育种的基因资源。图7表2参39。[Objective]Fragrance is one of the most important ornamental traits of Osmanthus fragrans.The purpose of this study is to identify the function of OfMYB1R47,a member of the MYB-related gene family of O.fragrans in the formation of aromatic volatiles,so as to provide a new gene node for the study of transcriptional regulation mechanism of aroma synthesis in O.fragrans.[Method]The MYB-related family gene OfMYB1R47 screened from the previous floral transcriptome data was used as the target gene,and O.fragrans‘Rixianggui’and Nicotiana benthamiana were used as materials.The characteristics and functions of OfMYB1R47 gene were analyzed by gene sequence and phylogenetic tree,RT-qPCR,subcellular localization,yeast self-activation,as well as the transient overexpression and GC-MS volatile metabolites test in N.benthamiana.[Result]The length of the open reading frame of OfMYB1R47 gene was 1485 bp,encoding 494 amino acids.Phylogenetic tree analysis showed that OfMYB1R47 had the highest homology gene in Olea europaea subsp.europaea.RT-qPCR analysis showed that the expression pattern of OfMYB1R47 gene increased first,and then decreased with the release of O.fragrans aroma,and the highest expression level was found at the early flowering stage of O.fragrans.Subcellular localization and yeast self-activation tests showed that OfMYB1R47 was mainly distributed in the nucleus and had self-activation activity.Compared with plants transformed into empty vectors,the contents of octanal,β-ionone and other aroma volatiles in the leaves of N.benthamiana with transient over-expression of this gene were significantly changed.[Conclusion]OfMYB1R47 has typical transcription factor characteristics,and its expression pattern is related to the release of O.fragrans,which is involved in the regulation of the synthesis of floral substances such asβ-ionone,and can be used as a gene resource for molecular breeding of O.fragrans.[Ch,7 fig.2 tab.39 ref.]

关 键 词：桂花 MYB-related转录因子 气相色谱-质谱联用(GC-MS) 花香 

分 类 号：S722.3[农业科学—林木遗传育种]