芒果类黄酮磺基转移酶基因克隆及表达分析

Cloning and Expression Analysis of a Flavonoid Sulfotransferases Gene from Mango(Mangifera indica)

利用前期芒果逆境差异显示的基因数据设计引物,从四季芒基因组DNA和cDNA中克隆了1条长为1208 bp的基因片段。生物信息学分析发现,该基因属于类黄酮磺基转移酶(flavonoid sulfotransferase)基因,在第71-334个氨基酸中包含一个保守的Sulfotransferase结构域,命名为芒果类黄酮磺基转移酶基因(MiST)。该基因编码341个氨基酸,分子量为85.14 ku,等电点为5.09,不含内含子,在不同芒果品种之间其核苷酸和氨基酸序列均高度保守。半定量表达模式分析显示,该基因在四季芒茎、叶、花和果中均有表达,但在谢花后20 d的小果和谢花后40 d的中果中的表达量较高,表明该基因可能与芒果果实中黄酮的生物合成有关。

Based on the early differential gene expressions database of mango stress samples, a 1 208 bp sequence was obtained. Bioinformatics analysis showed that the gene belonged to flavonoid sulfotransferase. It was named as M. indica flavonoids sulfotransferase gene（MiST） due to existing a conservative sulfotransferase domain structure between 71-334 amino acid sequence. The gene coded 341 amino acids with an estimated molecular weight and isoelectrie point of 85.14 Ku and 5.09, respectively. No introns were found in the MiST DNA sequences, but the nucleotide and amino acid sequences of MiST DNA sequences were highly conserved between different mango varieties. Semi-quantitative analysis showed that the MiST gene was expressed in stems, leaves, flowers and fruits in mango, but the gene expression level in the tissue of small fruits（20 days after the fallen petal） and middle fruits（40 days after the fallen petal）was higher than that of the other tissues. These results indicted that MiST gene might be play an important role in flavonoid biosynthesis in mango fruit.