茶树SBP-box转录因子的比较基因组学与遗传分析

Comparative Genomics and Genetic Analysis of SBP-box Transcription Factors in Camellia sinensis

SQUAMOSA启动子结合蛋白(SBP-box)是植物特异性转录因子,在植物生长发育中发挥重要作用。该研究利用生物信息学分析方法,对不同‘铁观音’、‘黄棪’、‘舒茶早’和‘龙井43’茶树基因组的SBP基因进行鉴定和比较,通过qRT-PCR技术分析CsTGY_SBP家族成员在不同茶树品种中的表达模式,为探究SBP基因在茶树杂种和亲本上的遗传规律提供参考。结果显示:(1)在茶树品种‘铁观音’、‘黄棪’、‘舒茶早’和‘龙井43’基因组中分别鉴定出21个、25个、24个和23个SBP家族基因。(2)系统进化树将其分为8个亚家族,共线性分析发现茶树和拟南芥、葡萄的SBP基因共线性关系与水稻相比更强,同物种内发现‘铁观音’与‘黄棪’的共线性关系更显著。(3)qRT-PCR结果表明,CsTGY_SBP5、CsTGY_SBP9和CsTGY_SBP14在F1‘金观音’中呈中亲表达的模式;大部分CsTGY_SBPs基因在F1‘黄观音’呈低于双亲表达模式,CsTGY_SBP5和CsTGY_SBP8在F1‘金牡丹’中显著高于亲本;CsTGY_SBP5、CsTGY_SBP7、CsTGY_SBP12、CsTGY_SBP16和CsTGY_SBP18在F1‘紫玫瑰’中的表达量显著高于亲本,呈超高亲表达的模式;CsTGY_SBPs基因在F1‘紫牡丹’中整体表达趋于亲本铁观音,在F1‘瑞香’中整体呈现低于亲本‘黄棪’的表达模式。研究表明,CsTGY_SBP5在F1‘金牡丹’和F1‘紫玫瑰’中的表达均显著高于亲本,推测CsTGY_SBP5可能是茶树杂种优势的重要调控因子。

SQUAMOSA promoter binding protein(SBP-box)genes encode a family of plant-specific transcription factors that play vital roles in plant growth and development.In this study,we used bioinformatics analysis methods to identify and compare the SBP gene family in different tea plant genomes of‘Tieguanyin’,‘Huangdan’,‘Shuchazao’and‘Longjing 43’.We used qRT-PCR technology to analysis the expression patterns of CsTGY_SBP gene family in different tea plants.This study provides a reference for exploring the inheritance of SBP genes in tea hybrids and parents.The results showed that:(1)there are 21,25,24 and 23 SBP genes were identified in the reference genome of Camellia sinensis‘Tieguanyin’,C.sinensis‘Huangdan’,C.sinensis‘Shuchazao’and C.sinensis‘Longjing 43’,respectively.(2)The SBP genes were phylogenetically classified into 8 subgroups.Collinearity analysis indicated that the orthology of CsTGY_SBP genes in Arabidopsis thaliana and Vitis vinifera was higher than that of Oryza sativa.The collinearity between C.sinensis‘Tieguanyin’and C.sinensis‘Huangdan’was found to be more significant in the same species.(3)The results of qRT-PCR showed that CsTGY_SBP5,CsTGY_SBP9 and CsTGY_SBP14 showed middle-affinity expression patterns in F1‘Jinguanyin’.Most of CsTGY_SBP genes showed a lower expression pattern than their parents in F1‘Huangguanyin’,while CsTGY_SBP5 and CsTGY_SBP8 were significantly higher than their parents in F1‘Jinmudan’.The expression levels of CsTGY_SBP5,CsTGY_SBP7,CsTGY_SBP12,CsTGY_SBP16 and CsTGY_SBP18 were significantly higher than their parents in F1‘Zimeigui’,showing a pattern of ultra-high parental expression.The expression of CsTGY_SBP genes in F1‘Zimudan’tends to be the famale parent‘Tieguanyin’on the whole,and the expression of CsTGY_SBP genes in F1‘Ruixiang’is lower than the male parent‘Huangdan’generally.CsTGY_SBP5,which is significantly higher than the parent in F1‘Jinmudan’and F1‘Zimeigui’,may be an important regulatory factor of tea plant heterosis.This study provides a reference for exploring the inheritance of SBP genes in tea hybrids and parents.