主要农作物钾吸收转运基因及其进化关系分析

Identification and Phylogenetic Analysis of Potassium Transporters in Major Crops

【目的】发掘主要农作物的钾吸收转运相关基因,并分析其进化关系。【方法】利用比较基因组学研究手段,在GenBank、EMBL、DDBJ和PDB数据库中进行搜索,并对其同源性进行分析。【结果】在小麦、大麦、玉米、烟草等作物中,发现了具有编码序列(cds)全长的44个与K+吸收转运相关的基因。其中,在大麦、玉米、葡萄、蚕豆及烟草中发现的属于HAK/KUP/KT家族的基因8个;在大麦、小麦、玉米、马铃薯、番茄及烟草等作物中,发现属于AKT家族的基因27个;在大麦与小麦中发现属于HKT家族的基因4个;在大麦、烟草与马铃薯中发现属于KCO家族的基因4个;只有1个属于KEA家族的基因,是在玉米中发现的。在本研究中,首次确定玉米基因组计划中克隆得到的ZM_BFb0024K15、ZM_BFc0028P03属于HAK/KUP/KT家族,而ZM_BFb0207I17则属于KEA家族。对这44个K+基因所分别进行的同源性分析结果表明,它们与代表检索基因的同源性较高,序列相似性最低为33%,最高为84%。【结论】在农作物中,存在众多的钾吸收转运相关基因。其中,大部分基因与拟南芥的相关基因有相对较高的同源性。

[Objective] The purpose of this experiment is to search all genes related to potassium absorption and transportation in major crops （except rice）, and analyze their phylogenetic relationships. [Method] With the help of comparative genome analysis method, searching was conducted across GenBank, EMBL, DDBJ, PDB NR database. Phylogenetic analysis was implemented within the searching result. [Result] 44 genes with complete cds related to potassium transporter families have been identified in wheat, barley, maze, tobacco etc （except rice）. Among these genes, 8 from barley, maze, grape and broad bean fall into HAK/KUP/KT family, 27 from wheat, barley, maze, potato, tomato, tobacco etc into AKT family, 4 from wheat and barley into HKT family and 4 from barley, tobacco and potato into KCO family. KEA family is represented by only one gene from maize. In this research, ZM_BFb0024K15, ZM_BFc0028P03 and ZM_BFb0207117 cloned in maize genome sequencing project were firstly identified as potassium transporters. The first two genes belong to HAK/KUP/KT family and the third to KEA family. Phylogenetic analysis showed that genes from each family are closely related to the query gene. The comparative identities are from 33% to 84%. [Conclusion] There are many genes related to potassium absorption and transportation in major crops （except rice）, and many of them are closely related to arabidopsis potassium genes.