亚洲棉、雷蒙德棉和陆地棉NRAMP基因家族的鉴定和进化分析

Identification and Evolution Analysis of NRAMP Gene Family in Gossypium arboretum,Gossypium raimondii and Gossypium hirsutum

自然抗性相关巨噬细胞蛋白(NRAMP)家族是跨膜转运蛋白家族,参与多种金属离子的转运过程。为了更好了解棉花NRAMP基因的成员和特征,二倍体和四倍体棉花之间的进化关系,本研究利用二倍体亚洲棉、雷蒙德棉和陆地棉基因组的氨基酸序列对三个棉种中的NRAMP家族成员进行鉴定,分析了NRAMP家族的种类、理化性质、进化关系、基因结构、蛋白基序、染色体定位、共线性关系和选择压力。结果显示,在二倍体亚洲棉基因组(A)中确定12个成员,在二倍体雷蒙德棉基因组(D)中确定15个成员,在四倍体陆地棉基因组(At, Dt)中确定23个成员。按照进化关系的远近将这50个成员分为3个亚类,进化关系较近的成员之间具有更为相似的理化性质、基因结构和蛋白质基序;通过和其他植物的进化关系分析发现,NRAMP基因在单子叶和双子叶植物分离前已经产生;染色体定位发现NRAMP在染色体上的分布并不规律;共线性分析和选择压力分析表明,片段复制在棉花NRAMP基因的遗传进化过程中发挥主导作用,同源基因对在进化过程中处于纯化选择。

The natural resistance-associatcd macrophage protein (NRAMP) family is a transmembrane transporter family, which participates in transport process of multiple metal ions. In order to better understand the members and characteristics of NRA MP gene in cotton and the evolutionary relationship between diploid and tetrapioid cotton, the NRAMP family members in diploid Gossypium arboretum, Gossypium raimondii and Gossypium hirsutum were identified by amino acid sequences of the genomes of these three cotton varieties. The species, physical and chemical properties, evolutionary relationships, gene stnicture, protein motifs, chromosome location, collinearity and selection pressure of NRAMP family were analyzed. The results showed that 12, 15 and 23 genes were identi fied in the genomes of the diploid progenitor Gossypium arboretum (A), Gossypium raimondii (D) and the tetrapioid Gossypium hirsutum (At, Dt), respectively. The 50 members were divided into three subfamilies based on the evolutionary relationship, and genes with closer relationship possessed similar physical properties, gene structure and protein motif. The analysis of evolutionary relationships with other plants showed that NRAMP gene had been produced before the isolation of monocotyledons and dicotyledons. Chromosomal localization revealed that the distribution of NRA MP on chromosomes was not regular. Colinearity analysis and selection pressure analysis indicated that fragment replication played a dominant role in the genetic evolution of NRA MP gene in cotton, and homologous genes were in the purification and selection process.