延边苹果梨PyDFR基因的克隆及表达分析

Molecular Cloning and Expression Analysis on PyDFR Gene of Pingguoli in Yanbian

以延边苹果梨果实为试材,采用同源克隆及实时荧光定量PCR的试验方法,研究PyDFR基因在果实着色过程中的表达特性及其与花青苷积累的关系。结果表明:PyDFR基因cDNA全长1 039bp,推断其含有1个843个核苷酸的开放阅读框(ORF),编码281个氨基酸,推导的蛋白分子量为32kDa,理论等电点pI为6.32。同源性分析表明,PyDFR基因与沙梨的(JQ749637.1)DFR基因的同源性高达99%;实时荧光定量PCR分析表明,PyDFR基因受到光诱导表达量迅速上升,去袋后1d即达到最大值,随后迅速下降,最终稳定在同一表达水平,与果实着色和花色苷含量测定的结果相对应,即PyDFR基因对果实花色素苷积累有一定的促进作用。

Taking the Pingguoli in Yanbian as material,the relationship between the expression and the accumulation of anthocyanin during the pigmentation of Pingguoli was analyzed by the homology cloning technology,and the real-time fluorescent quantitative PCR technique.The results showed that,the full-length cDNA of PyDFRincluded 1 039 basepair and opened reading frame encompassed 843 bp encoding apolypeptide of 281 amino acids residues with a calculated molecular weight（MV）of 32 kDa and isoelectric point theory（pI）of 6.32.The homology analysis revealed that this cDNA and Pyrus pyrifolia（JQ749637.1）was 99%.Real-time fluorescent quantitative RT-PCR results indicated the expression level of PyDFR were markedly enhanced in the sunlit side,and reached a maximum value at 1day after debagging,then started decline rapidly,but finally expressed stably in the same level.The color code and anthocyanins content produced results essentially in agreement with these figures.In addition that had a certain role in promoting the accumulation of fruit anthocyanin.