枇杷EjNAC82的克隆及其对类胡萝卜素合成基因EjPSY、EjBCH的转录激活分析  

Cloning of EjNAC82 in Loquat and Its Transcriptional Regulation on Carotenoid Biosynthetic Genes EjPSY and EjBCH

作　　者：柴吉钏 王康 杨民杰 董婉琪 曹士锋 陈伟[1] 杨震峰[1] 施丽愉[1] CHAI Jichuan;WANG Kang;YANG Minjie;DONG Wanqi;CAO Shifeng;CHEN Wei;YANG Zhenfeng;SHI Liyu(College of Biological and Environmental Sciences,Zhejiang Wanli University,Ningbo,Zhejiang 315100)

机构地区：[1]浙江万里学院生物与环境学院,浙江宁波315100

出　　处：《核农学报》2022年第6期1115-1126,共12页Journal of Nuclear Agricultural Sciences

基　　金：浙江省自然科学基金重点项目(LZ21C200002);浙江省教育厅一般科研项目(Y201942714);宁波市自然科学基金项目(2019A610432);浙江省属高校基本科研业务费项目成果。

摘　　要：为了探讨NAC转录因子对枇杷果实类胡萝卜素代谢的调控机制,以大红袍(红肉枇杷)和白沙(白肉枇杷)为试验材料,利用RNA-Seq技术对大红袍和白沙进行转录组测序,通过分析两个品种间的转录组差异,初步筛选并克隆出了1个枇杷NAC转录因子,命名为EjNAC82。生物信息学技术分析结果发现,EjNAC82具有NAC转录因子特有的结构域、理化性质和蛋白质结构特点,是典型的NAC转录因子家族基因。亚细胞定位试验发现该转录因子定位于细胞核。实时荧光定量PCR结果表明,EjNAC82在枇杷老叶中的表达量高于根、芽、嫩叶、老叶、嫩枝、老枝、幼果和熟果。EjNAC82在果皮和果肉成熟过程中的表达模式相同,均呈先上升后下降再上升的趋势。随着果实的成熟,EjNAC82在大红袍果肉中的表达显著高于白沙(P<0.05)。EjNAC82在大红袍果皮S1、S2、S4时期的表达显著高于白沙。LUC/REN双荧光素酶试验结果表明,EjNAC82对EjPSY1、EjPSY2和EjBCH启动子具有激活作用。这些结果表明EjNAC82可能通过调控EjPSY1、EjPSY2和EjBCH基因的表达从而正向调控枇杷果实中类胡萝卜素的合成。本研究结果为揭示NAC转录因子对枇杷果实类胡萝卜素积累的转录调控功能提供了理论依据。Abstact:In order to explore the correlation between transcription factors and carotenoid accumulation in the red-fleshed Dahongpao and white-fleshed Baisha loquat fruit,one NAC transcription factor named EjNAC82 was preliminarily selected based on the loquat transcriptome database and cloned by RT-PCR.Bioinformatics analysis showed that the characteristics of EjNAC82 were basically consistent with NAC gene in other species with a NAC domain.Subcellular localization revealed that EjNAC82 were primarily localized to nucleus.Higher transcripts of EjNAC82 were observed in mature leaves than in any other tissues such as roots,buds,young leaves,burgeons,mature branches,young and mature fruits.Meanwhile,the expression of EjNAC82 was significantly(P<0.05)higher in Dahongpao pulps than that in Baisha during ripening,and was also higher in Dahongpao peels at stages S1,S2 and S4.Finally,we found that EjNAC82 transcription factor had transcriptional activation effect on the promoters of EjPSY1,EjPSY2 and EjBCH with dual-luciferase reporter assays.Therefore,it can be speculated that EjNAC82 may promote carotenoid synthesis in loquat by regulating the expression of EjPSY1,EjPSY2 and EjBCH genes.These results provide the theoretical foundation for further functional analysis of NAC transcription factors in loquat.

关 键 词：枇杷果实 类胡萝卜素 NAC 转录因子 

分 类 号：S667.3[农业科学—果树学]