芸薹属同源异源六倍体(B^(c)B^(c)C^(c)C^(c)C^(o)C^(o))染色体片段缺失的鉴定及其在色泽形成基因定位中的应用  

Identification of chromosome deletion in synthesized Brassica auto-allohexaploids and its application in mapping genes of pigment synthesis

作　　者：邱杰 王泰 蔡博伟 段圣省 徐林珊 陈晓迪 王晶 葛贤宏[1] 李再云[1] QIU Jie;WANG Tai;CAI Bo-Wei;DUAN Sheng-Xing;XU Lin-Shan;CHEN Xiao-Di;WANG Jing;GE Xian-Hong;LI Zai-Yun(College of Plant Science and Technology,Huazhong Agricultural University,Wuhan 430070,Hubei,China)

机构地区：[1]华中农业大学植物科学技术学院,湖北武汉430070

出　　处：《作物学报》2023年第11期2902-2912,共11页Acta Agronomica Sinica

基　　金：国家重点研发计划项目(2021YFD1600505)资助。

摘　　要：多倍化导致物种的基因组趋于复杂,基因拷贝数增多,为性状的遗传解析及基因定位、功能分析带来挑战。染色体片段缺失往往导致相应的表型变化,而控制这些表型的基因就位于缺失片段内。根据这个原理可以利用染色体缺失品系迅速、准确地将相关基因定位于特定染色体上/染色体区段内。本研究以紫株、黄花埃塞俄比亚芥(Brassica carinata,B^(c)B^(c)C^(c)C^(c),2n=34)为母本与绿株、白花芥蓝(Brassica oleracea,C^(o)C^(o),2n=18)杂交合成同源异源六倍体(B^(c)B^(c)C^(c)C^(c)C^(o)C^(o))。在杂种幼胚培养、加倍过程中,同一个幼胚愈伤组织中分化出2种表型不同的六倍体植株:紫株、淡黄花与绿株、白花。细胞学观察、荧光原位杂交、基因组重测序分析表明与紫株相比,绿株基因组B04染色体存在大片段缺失。转录组分析表明,缺失区段内的DFR基因以及位于参考基因组B03染色体上的MYB90基因可能为控制紫株六倍体紫色形成的关键基因;而位于缺失区段内的Z-ISO以及CRTISO2则是控制黄色花瓣形成的关键基因。Polyploidy leads to the complexity of individual genomes and an increase of gene copies,which brings challenges to the genomic and genetic analysis.The deletion of a chromosome or chromosome fragment often leads to corresponding phenotypic changes,and the genes controlling these traits are located within the deleted fragments.According to this principle,chromosome dele-tion was usually used to map genes in a specific chromosome or chromosome fragment.In this study,a Brassica auto-allohexaploid(B^(c)B^(c)C^(c)C^(c)C^(o)C^(o))was synthesized by the hybridization between B.carinata(2n=34,B^(c)B^(c)C^(c)C^(c))and B.oleracea(C^(o)C^(o),2n=18).Two young hexaploid plants were differentiated from the callus of the same immature embryo during embryo rescue on MS medium with colchicine and hormone.However,while one plant showed purple leaves and stems and light-yellow flowers as its maternal parent B.carinata,the other plant had green leaves and stems and white flowers like the paternal parent B.oleracea.Cytological observation,fluorescence in situ hybridization(FISH),and genome re-sequencing analysis showed that a large fragment of chromosome B04 was absent in green plant.Transcriptome analysis showed DFR gene in the deletion region and MYB90 on the reference genome B03 chromosome may be the key genes controlling the purple color formation on leaves and stems,while Z-ISO and CRTISO2 were two genes within deletion region determining the formation of yellow flowers in hexaploids.

关 键 词：芸薹属 六倍体 染色体缺失 花青素 类胡萝卜素 

分 类 号：Q943.2[生物学—植物学]