辣椒E2基因家族的鉴定及分析

Identification and Analysis of E2 Gene Family in Pepper(Capsicum annuum L.)

【目的】泛素结合酶E2(UBC)作为泛素蛋白酶体途径中将泛素转移至靶蛋白的重要中转酶,与植物的生长发育和许多胁迫有关。从辣椒全基因组中鉴定E2基因家族成员,分析相关基因表达模式,为后续研究提供理论基础。【方法】基于辣椒全基因组信息,利用生物信息学方法对E2基因家族进行鉴定,系统分析该家族成员的基本理化性质、亚细胞定位、染色体定位、基因结构、系统进化关系、顺式作用元件、蛋白质互作网络、非生物胁迫响应与组织器官表达模式。【结果】辣椒E2家族有48个成员,在11条染色体上呈不均匀地分布,其编码蛋白主要定位于细胞外和细胞核中;通过对辣椒、番茄和拟南芥的比较进化分析将其分为GroupⅠ-GroupⅧ亚族,同一亚族具有相似的蛋白保守基序和基因结构;发现共有26个蛋白之间存在互作;顺式作用元件分析表明,CaUBC基因启动子区含有大量光响应、激素响应元件,上游2000 bp区域中存在多种与生长发育和抗逆性相关的顺式作用元件;CaUBC参与胁迫响应,在不同非生物胁迫和激素处理下,将其分为3类,其中高温环境下第3类基因为高表达;在组织器官中表现出不同的表达,其中CaUBC38在果实中的表达量变化较为明显,进行RT-qPCR分析发现,50 d相对表达量最高,10 d表达量最低。【结论】获得48个辣椒E2(CaUBC)基因,揭示了E2家族不同成员在辣椒生长发育和非生物胁迫过程中的表达特征。

【Objective】Ubiquitin-binding enzyme E2(UBC)is an important transit enzyme in the ubiquitin-proteasomal pathway that transfers ubiquitin to target proteins,which is involved in plant growth and development and many stresses.The E2 gene family members were identified from the whole genome of pepper,and the expression patterns of related genes were analyzed,which provided a theoretical basis for subsequent research.【Method】Based on the genome-wide information of pepper,the E2 family was identified by bioinformatics.The basic physio-chemical properties,subcellular localization,chromosomal localization,gene structure and phylogenetic analysis,cis-acting elements,abiotic stress response,tissue and organ expression patterns,and protein-protein interaction network of the family members were systematically analyzed.【Result】There were 48 members in the E2 gene family,which were unevenly distributed on 11 chromosomes,and its encoded proteins were mainly localized in the extracellular and nucleus.After comparative evolutionary analysis of pepper,tomato and Arabidopsis thaliana,they were divided into the Group I-Group XIII subfamily,which had similar conserved protein motifs and gene structures.A total of 26 proteins were found to interact.The cis-element analysis showed that the promoter region of CaUBC gene contained a large number of lightresponsive and hormone-responsive elements,and there were a variety of cis-acting elements related to growth,development and stress resistance in the upstream 2000 bp region.CaUBC was involved in the stress,under different abiotic stresses and hormone treatments,they were divided into three categories,among which the third type of genes were highly expressed in high temperature environment;different expressions showed in tissues and organs,among which the expression of CaUBC38 in fruits changed significantly.RT-qPCR analysis showed that the relative expression was the highest at 50 d and the lowest at 10 d.【Conclusion】The 48 members of E2(CaUBC)gene family are systematically identified from the pepper genome.The expression characteristics of CaUBC family members during its growth,development,and abiotic stress responses are revealed.