日本结缕草ZjSPL4基因的克隆、亚细胞定位及表达分析

Cloning, Subcellular Localization and Expression Analysis of ZjSPL4 Gene in Zoysia japonica Steud

根据转录组数据库,通过同源克隆获得结缕草ZjSPL4基因,开放阅读框为1 002 bp,编码333个氨基酸,该基因具有SBP基因家族保守域。ZjSPL4编码的蛋白分子量为36.381 63 k D,理论等电点(pI)为8.79,总平均亲水性为-0.707,属于亲水性蛋白。二级结构预测结果显示ZjSPL4蛋白主要由无规则卷曲(Cc)、α螺旋(Hh)构成。ZjSPL4蛋白与其他植物的SBP蛋白总体相似度为53.71%,通过系统进化树分析发现ZjSPL4与谷子和二穗短柄草中的SPL基因亲缘关系较近。ZjSPL4蛋白亚细胞定位结果显示,其编码的蛋白定位于细胞核中。同时日本结缕草ZjSPL4基因受到GA、ABA、蔗糖、低温的诱导,说明该基因可能参与结缕草花芽分化以及抗逆反应等过程。因此,克隆分析结缕草ZjSPL4基因可为结缕草花芽分化与抗性机制研究以及分子育种提供一定参考。

According to the transcriptome d atabase, the ZjSPL4 g ene of Zoysia japonica was obtained through homologous cloning. The open reading frame was 1 002 bp, encoding 333 amino acids. The gene had a conserved domain of SBP gene family. The molecular we ight of the protein encoded by ZjSPL4 was 36.381 63 k D, the theoretical isoelectric point（p I） was 8.79, and the total average hydrophilicity was-0.707, which belonged to hydrophilic protein. The results of secondary structure prediction showed that ZjSPL4 protein was mainly composed of irregular curling（Cc） and alpha helix（Hh）. The overall similarity of ZjSPL4 protein to SBP proteins in other plant was 53.71%. Phylogenetic tree analysis indicated that ZjSPL4 had close relationship with SPL gene in Setaria italica and Brachypodium distachyon. The result of the subcellular localization of ZjSPL4 protein showed that its encoded proteins were located in the nucleus. At the same time, the ZjSPL4 gene was induced by GA, ABA, sucrose and low temperature, which indicated that the gene might be involved in the process of flower bud differentiation and anti-inversion. Therefore, cloning and analysis of Zoysia japonica ZjSPL4 gene could provide a theoretical basis for the study of flower bud differentiation and resistance mechanism of Zoysia japonica and molecular breeding.