香蕉MaEIL4的分离鉴定及其在果实采后成熟过程中的差异表达分析

Isolation and Identification of MaEIL44 and Differential Expression in Postharvest Banana Fruit Ripening Process

为了明确香蕉果实中参与乙烯信号转导的关键基因,本研究在转录水平上对香蕉中的9个Ethylene insensitive 3-like(MaEIL)基因在果实采后成熟过程中的差异表达特性进行分析,找到关键基因并克隆其全长,采用生物信息学方法对其理化特性,结构特征,亚细胞定位进行分析,采用荧光实时定量PCR方法对其果实采后不同处理条件下的差异表达特性进行了深入研究。结果表明,MaEIL4在果实采后成熟过程中高水平表达。MaEIL4全长4314 bp,单一外显子。其开放阅读框全长1908 bp,编码635个氨基酸,分子式为C_(3104)H_(4837)N_(883)O_(970)S_(34),分子量为71.13 kD,等电点为5.70,属于亲水性氨基酸。该基因具有典型的Ethylene insensitive 3(EIN3)结构域。该基因编码蛋白质定位于细胞核中。MaEIL4在香蕉果实采后成熟过程中的表达明显受到外源乙烯的诱导,受1-MCP的抑制,表明MaEIL4参与了果实成熟早期乙烯信号的转导,在果实采后成熟过程中发挥着重要的作用。研究结果有助于深入解析香蕉果实采后成熟过程中乙烯信号转导的分子机制,丰富了果实成熟调控的理论,也为香蕉果实成熟与品质改良提供了靶基因,具有重要的应用价值。

In order to understand the key genes involved in ethylene signal transduction in banana fruits,expression characteristics of nine ethylene insensitive 3-like(MaEIL)genes from banana fruits have been investigated in transcription level.The key gene has been cloned and its physical and chemical properties,structure,subcellular localization has been analyzed by bioinformatics.Moreover,the differential expression characteristic during fruit ripening process with different treatments has been further investigated by real time quantitative PCR.The result indicated that MaEIL4 highly expressed during fruit ripening process.The full length of MaEIL4 was 4314 bp with only one exon.The open reading frame was 1908 bp and encoded 635 amino acids.The molecular formula was C_(3104)H_(4837)N_(883)O_(970)S_(34).The molecular weight was 71.13 kD.The isoelectric point was 5.70 and belonged to hydrophilic amino acid.MaEIL4 has a typical ethylene insensitive 3(EIN3)domain and localized in cell nucleus.The expression of MaEIL4 during fruit ripening process with different treatments was greatly improved by exogenous ethylene and suppressed by 1-MCP,which suggested that MaEIL4 participated in ethylene signal transduction and played important role in postharvest banana fruit ripening process.These results will help to deeply understand the molecular mechanism of ethylene signal transduction and enrich the theory of banana fruit ripening regulation.These results provide target gene for banana fruit ripening and quality improvement and has important application value.