桃Aux/IAA家族基因鉴定及在果实成熟过程中的表达分析

通过生物信息学鉴定桃基因组中生长素/吲哚乙酸(Aux/IAA)基因家族,并对其在溶质型和硬质型桃果实成熟阶段的表达水平进行q RT-PCR检测。结果表明:桃Aux/IAA基因家族包含22个成员,这些基因集中分布在5条染色体上,以第1条染色体上含有最多,为8个。大部分Aux/IAA基因包含高度保守的Ⅰ、Ⅱ、Ⅲ和Ⅳ功能域,聚类分析表明其分为10类。基因结构分析显示这些基因包含2~5个外显子。荧光定量PCR分析表明10个Aux/IAA基因在溶质型桃果实的表达量高于对应时期硬质型桃果实,其中5个基因随着溶质型桃果实的成熟上调表达,特别是ppa010303m、ppa010871m和ppa020369m。试验结果表明桃Aux/IAA家族成员在结构上高度保守,其中多个成员(尤其是ppa010303m、ppa010871m和ppa020369m等)可能参与调控桃果实的成熟。

Identification and Expression Profiling of Aux/IAA Family Gene During Peach Fruit Ripening

Auxin/indole-3-acetic acid (Aux/IAA)is involved in plant growth,development,and multiple other processes.In this study,the Aux/IAA gene family in the peach genome was identified and analyzed by bioinformatics,additionally,the expression levels of Aux/IAA genes were detected by qRT-PCR in melting-flesh and stony-hard peach fruits during fruit ripening.The results showed that 22 PpAux/IAA candidate genes were found in the peach genome.A chromosome mapping analysis revealed that PpAux/IAA genes were distributed with different densities over 5 chromosomes,with the largest number of PpAux/IAA genes on chromosome 1 (8 genes).The DNA-binding and Aux/IAA domains,as well as motif Ⅰ,Ⅱ,Ⅲ and Ⅳ of the PpAux/IAA gene family were highly conserved.The phylogenetic analysis revealed that PpAux/IAA gene family was divided into 10 groups.The results of an intron-exon structure analysis indicated that PpAux/IAA gene family members were composed of 2-5 exons.qRT-PCR results indicated that the expression level of ten PpAux/IAA genes in melting-flesh peach fruits were higher than in stony-hard peach fruits,and the expression level of 5 genes were upregulated in melting-flesh fruits during fruit ripening,especially for ppa010303m,ppa010871m,and ppa020369m.These results suggested that the PpAux/IAA gene family members are highly and structurally conserved,and some of them (especially forppa010303m,ppa010871m and ppa020369m) are involved in regulating peach fruit ripening.