不同钾水平下花魔芋差异表达基因分析

摘要

In order to investigate the response mechanism of Amorphophallus konjac plants growing under different potassium levels,the total RNA of the leaves of Amorphophallus konjac Fuyuan on the fifth day after potassium sulfate(low,medium and high level)was applied.Then cDNA was synthesized,and the differentially expressed genes of Amorphophallus konjac Fuyuan leaves under low,medium and high potassium sulfate were amplified by optimized cDNA-SRAP,and their bioinformatics was analyzed.The results showed that 507 gene segments were amplified by 29 pairs primer combinations,including 126 differentially expressed gene segments.Compared with the medium potassium level,19 inhibited expressed fragments,14 induced expressed fragments,29 up-regulated expressed fragments,and 64 down-regulated expressed fragments were found in the low and high potassium levels.After recycling 13 differentially expressed gene segments of good quantity,9 homologous sequences matched with them in NCBI.Except for 4 nucleotide sequences matching with higher homology to the known function genes (glutaminyl-tRNA synthetase,β-ATP synthase,YchFGTP-binding protein YchF,ribonucleotide reductase) and 5 nucleotide sequences matching with higher homology to the assumption genes or the predict genes,other differentially expressed gene segments were not found,which might be some new genes of Amorphophallus konjac Fuyuan associated with potassium nutrition uptake.The specific function of the new genes will be further studied and analyzed in the future.%为了探索魔芋对不同水平钾素营养的反应机制，提取施用低、中、高水平硫酸钾5 d 后的富源花魔芋叶片总 RNA，合成了 cDNA，采用优化的 cDNA-SRAP 技术体系分析了在低钾、中钾、高钾水平下富源花魔芋叶片的差异表达基因，并对其进行了生物信息学分析。结果显示：29对引物组合共扩增出507条基因片段，其中差异片段126条。相对于中钾处理，低钾、高钾处理的差异片段包括抑制型表达片段19条，诱导型表达片段14条，上调表达型片段29条，下调表达型片段64条。选取表达量高的13条差异片段进行回收测序，并在 NCBI 上进行 BLAST 比对，共比对出9条差异片段的同源序列，其中4条与已知功能基因（谷氨酰胺酰-tRNA 合成酶、β-ATP 合成酶、GTP 结合蛋白、核苷酸还原酶）有较高同源性，5条与假定基因或预测基因同源性较高，剩余序列未找到同源序列，可能是一些新的魔芋与钾营养吸收利用相关的基因，具体功能还有待于进一步研究。