香石竹WRKY家族全基因组鉴定及其表达分析

Genome-wide Identification and Expression Analysis of WRKY Gene Family in Dianthus caryophyllus

以拟南芥WRKY蛋白序列及保守结构域种子文件(PF03106)检索香石竹(Dianthus caryophyllus L.)基因组数据库,共鉴定出香石竹WRKY家族基因DcaWRKY 53个,分别编码161~747个氨基酸,蛋白质平均分子量在18.27~82.58 kD之间,等电点在5.07~10.25之间,内含子数1~5。系统发育分析显示,DcaWRKY可分为3组,其中groupⅡ又可进一步分为5个亚组。DcaWRKY结构域具有高度保守性,皆为WRKYGQK七肽结构域,偶有变型。DcaWRKY20的N端WRKYGQK七肽结构域出现缺失,形成了WRK的缺失变型;DcaWRKY39的C端WRKYGQK七肽结构域中的K突变成了N,形成了WRNYGQK七肽结构域;DcaWRKY48为WRKYGKK七肽结构域。DcaWRKY蛋白序列中至少存在10个保守基序,同源关系较近的成员具有相似的保守基序。启动子区的顺式作用元件分析显示DcaWRKY启动子区含有大量与光信号、植物激素、胁迫和分生组织等相关的功能域。转录组数据分析结果显示,有20个DcaWRKY在不定根形成过程中表现出不同程度地上调或下调,推测其可能在香石竹插穗不定根形成过程中发挥重要作用。定量分析结果表明DcaWRKY11、DcaWRKY13、DcaWRKY15、DcaWRKY22、DcaWRKY23、DcaWRKY31及DcaWRKY39的表达模式与转录组结果基本一致,且在香石竹不定根生长过程中表现出多样性。此外,DcaWRKY在生长素处理组和对照组中的表达水平无显著差异性,说明DcaWRKY对生长素不敏感。

The WRKY genes of carnation(DcaWRKY)were identified from Dianthus caryophyllus genomic database based on the WRKY protein sequences of Arabidopsis thaliana and the conserved domain sequence of WRKY proteins(PF03106).In total,53 DcaWRKY members were identified in the carnation genome,with the amino acid size,molecular weight of protein(average),isoelectric point and the gene intron numbers varying from 161-747 aa,18.27-82.58 kD,5.10-10.52 and 1-5 respectively.According to phylogenetic analysis,DcaWRKYs can be divided into three groups and groupⅡcan be further divided into five subgroups.DcaWRKY conserved domain analysis revealed three mutations in the WRKY domain,the WRKYGQK heptapeptide domain in N terminal of DcaWRKY20 were lack of‘YGQK’and formatted the missing variant WRK,and the K in the heptapeptide domain of WRKYGQK at the C terminal of DcaWRKY39 is mutated to N,forming the heptapeptide domain of WRNYGQK and DcaWRKY48 is the WRKYGKK heptapeptide domain.In addition,Conserved motifs analysis showed that there were at least 10 motifs in DcaWRKY members and they have similar conserved motifs when they are in a closer phylogenetic relationship.Cis-acting element analysis in the promoter region showed that DcaWRKYs contained a large number of functional domains related to light signal,plant hormone,stress and meristem.Based on the transcriptomic data analysis,there were 20 DcaWRKY gene family members up-regulated or down-regulated during adventitious root formation,and we speculated that these genes may play an important role in the formation of adventitious roots in carnations cuttings.And the qRT-PCR analysis revealed that the mRNA expression patterns of DcaWRKY11,DcaWRKY13,DcaWRKY15,DcaWRKY22,DcaWRKY23,DcaWRKY31 and DcaWRKY39 showed a fairly good match to the RNA-seq analysis and showed diversity in the growth process of adventitious roots.In addition,there was no significant difference in the expression of DcaWRKYs between auxin group and control group,indicating that the DcaWRKYs is not sensitive to auxin.