野生种花生GLP家族基因的鉴定与特征分析

Genome-wide Identification and Character Analysis of Germin-like Protein Family Gene in Arachis duranensis and Arachis ipaensis

GLP是一类普遍存在于植物界的cupin超家族基因,在调控植物生长发育和抗逆反应中起到多种重要作用。本研究从全基因组水平研究野生种花生GLP基因家族,共鉴定出38个GLP基因。结构域分析显示,绝大多数花生GLP都含有保守的cupin保守结构;基因结构和系统发育分析表明38个花生GLP家族基因分成Subfamily Ⅰ、Subfamily II和Gymosperm subfamily 3个亚家族,分别有20个、10个和8个成员,其中Subfamily I内含子/外显子结构较一致,无显著差异;Gymosperm subfamily中GLP基因内含子长度差异最大,最长达6.3 kb;Subfamily II中的基因内含子数量差异最显著,最多达5个。说明基因结构与系统进化有一定的关系。染色体定位分析显示,花生GLP基因在花生17条染色体中的分布呈不均匀性,存在5个基因簇,其中染色体A06上分布最多,为9个;其次是B06,分布6个。基因表达分析显示,在22个不同的组织中,仅有8个野生种花生GLP家族基因呈现出差异表达,其中6个属于Subfamily Ⅱ,且表达总量显著高于其他基因,而Subfamily I成员均未检测到表达。该结果将为今后花生GLP家族基因的功能研究与利用提供参考。

The germin-like protein family genes,an important class of plant-ubiquitous proteins characterized by the cupin domain,play important roles and variety activities in biological processes.Available genome sequences of peanut(Arachis hypogaea L.)have promoted the identification GLP family genes.We identified 38 GLP genes in peanut genomes.The results of domain analysis indicated that the GLP regions contained a highly conserved cupin motif.The results of structural and phylogenetic analysis revealed that 38 peanut GLP genes were classified into Subfamily Ⅰ(20),Subfamily Ⅱ(10)and Gymosperm subfamily(8).Intron/exon structure of Subfamily was consistent without significant difference.In Gymosperm subfamily,the difference of GLP gene intron length was the most significant,which was up to 6.3 kb.The number of introns in Subfamily Ⅱ was the most obvious,which up to five introns.This result indicates that there is a certain relationship between gene structure and phylogenetic evolution.Chromosome mapping analysis showed that wild peanut GLP genes were distributed with different densities on 17 chromosomes with five gene clasters.The largest number of peanut GLP genes were found on chromosomes A06(9 genes),followed by chromosome B06(6 genes).Gene expression analysis showed that,in 22 different tissues,only 8 out of 38 wild peanut GLP family genes exhibited differential expression,six of them belonged to Subfamily II and expressed significantly higher than other genes.However,expression was not detected in Subfamily I in 22 tissues.These results will facilitate functional analysis and utilization of GLP genes in peanut.