马尾松PmMADS13基因的克隆与表达分析

Cloning and Expression Analysis of PmMADS13 Gene in Pinus massoniana

SOC1/TM3是MADS-box家族一员,它能介导多条开花途径的信号整合,从而调控开花的时间和花器官的发育。为了解SOC1类基因在马尾松生殖生长中的作用,从转录组测序结果中筛选到一条SOC1类同源基因,设计特异性引物,采用c DNA末端快速克隆(RACE)技术,获得该基因的全长cDNA序列为1147 bp,包括666 bp的开放阅读框(ORF),共编码220个氨基酸,命名为PmMADS13。氨基酸序列比对分析表明,此蛋白包含典型的MADS-box和K-box结构域,C末端具有高度保守的SOC1 motif基序;进化树分析表明马尾松PmMADS13与油松的DAL9基因、辐射松的MADS9基因、火炬松的MADS13基因的亲缘关系最近,属于SOC1/TM3亚家族;RT-PCR分析显示,PmMADS13在马尾松生殖器官雌花、雄花中均有高表达,其次是茎端和针叶,在根部组织中的表达量最低。推测PmMADS13是参与马尾松成花的重要基因。

SOC1/TM3 is a member of the MADS-box family,which can mediate the signal integration of multiple flowering pathways to regulate flowering time and the development of floral organs.In order to understand the role of SOC1 genes in the reproductive growth of Pinus massoniana,a SOC1 homologous gene was screened from transcriptome sequencing results,and specific primers were designed.The rapid amplification of cDNA ends(RACE)technique was adopted to obtain the full-length cDNA sequence of the gene,which was 1147 bp,including 666 bp open reading frame(ORF).A total of 220 amino acids were encoded and the gene was named as PmMADS13.The amino acid sequence alignment analysis showed that the protein contained typical MADS-box and K-box domains,with a highly conserved SOC1 motif at its C-terminal;phylogenetic tree analysis indicated that PmMADS13 gene of Pinus massoniana was most closely related to DAL9 gene of Pinus tabulaeformis,MADS9 gene of Pinus radiata and MADS13 gene of Pinus taeda,belonging to SOC1/TM3 subfamily;RT-PCR analysis showed that PmMADS13 was highly expressed in both male and female flowers of reproductive organs in Pinus massoniana,followed by expressing in stem tip and needle leaves,and had the lowest expression level in root tissues.It was speculated that PmMADS13 was an important gene involved in the flower formation of Pinus massoniana.