摘要
为探究白花泡桐蔗糖合成酶基因(SUS)的功能和表达调控机制,以白花泡桐健康苗(PF)和丛枝植原体感染幼苗(PFI)为试验材料,克隆得到PfSUS2基因及其上游启动子序列,对PfSUS2基因进行生物信息学分析、组织特异性以及胁迫响应分析,并通过荧光素酶基因表达技术验证PfSUS2启动子的转录激活活性。结果表明:白花泡桐PfSUS2基因编码区长度为2 418 bp,编码805个氨基酸,其编码的蛋白质分子质量为92.0 kDa,理论等电点为6.21,含有66个磷酸化位点,具有典型的蔗糖合成酶和糖基转移酶结构域,主要定位于细胞质中。PfSUS2蛋白质的二级结构主要由α-螺旋组成,可能以同源四聚体存在。进化分析结果表明,PfSUS2蛋白质属于SUSⅠ组双子叶植物亚组,与芝麻和楸树的SUS蛋白质同源性最高。PfSUS2基因在白花泡桐茎和根中的表达量较高,并且可响应泡桐丛枝病和低磷胁迫。PfSUS2基因上游2 003 bp的启动子序列具有转录激活活性;该区域包含了胁迫、激素和光响应顺式元件,表明PfSUS2基因表达受到多种因素的调控。
To investigate the function and expression regulation mechanism of the sucrose synthase gene(SUS)in Paulownia fortunei,this study used the healthy seedlings(PF)and Phytoplasma-infected seedlings(PFI)of Paulownia fortunei as experimental materials.PfSUS2 and its upstream promoter sequence were cloned.Bioinformatics analysis,tissue-specific expression analysis,and stress response analysis of PfSUS2 were conducted,and the transcriptional activation activity of the promoter was verified by luciferase gene expression experiments.The results showed that the coding region of PfSUS2 was 2418 bp long,encoding 805 amino acid residues.The encoded protein had a molecular weight of 92.0 kDa,a theoretical isoelectric point of 6.21,66 phosphorylation sites,and typical sucrose synthase and glycosyltransferase domains,and it was primarily localized in the cytoplasm.The secondary structure of PfSUS2 was mainly composed ofα-helices and this protein might exist as a homotetramer.The phylogenetic analysis revealed that PfSUS2 belonged to the dicotyledonous subgroup of the SUSⅠgroup and had the highest homology with the SUS proteins of Sesamum indicum and Catalpa bungei.PfSUS2 was highly expressed in the stems and roots of Paulownia fortunei and responded to Paulownia-induced witches'-broom disease and low phosphorus stress.The 2003 bp upstream promoter sequence of PfSUS2 exhibited transcriptional activation activity,and this region contained cis-elements responsive to stress,phytohormones,and light,which indicated that the expression of PfSUS2 was regulated by multiple factors.
作者
吕胡杨
邓敏捷
赵蕾
吕资晗
范国强
LüHuyang;DENG Minjie;ZHAO Lei;LüZihan;FAN Guoqiang(College of Forestry,Henan Agricultural University,Zhengzhou,Henan 450046,China)
出处
《森林与环境学报》
北大核心
2025年第5期491-500,共10页
Journal of Forest and Environment
基金
河南省科技研发计划联合基金:项目“泡桐分枝关键基因筛选及泡桐抗丛枝病新种质创制”(222103810007)
河南省高等学校重点科研项目“白花泡桐独脚金内酯相关基因的鉴定与功能分析”(23A220002)
河南省大学生创新训练计划项目“白花泡桐转录因子BES1/BZR1基因克隆与分析”(202410466042)。
关键词
白花泡桐
蔗糖合成酶
启动子
胁迫响应
基因表达
Paulownia fortunei
sucrose synthase
promoter
stress response
gene expression
作者简介
第一作者:吕胡杨(2001-),女,硕士研究生,从事泡桐生物学研究。Email:13949304515@163.com。;通信作者:范国强(1964-),男,教授,从事泡桐生物学研究。Email:zlxx64@126.com。
