论文部分内容阅读
钾通道蛋白是植物吸收钾的主要途径之一。本研究利用RT-PCR技术从低钾胁迫的甘蔗根系中克隆得到钾通道蛋白基因,命名为SsAKT1,全长为3119bp,开放阅读框为2658bp,包含885个氨基酸。SsAKT1基因编码的蛋白与其他作物中AKT1基因具有高度的同源性,一致的氨基酸比例在61%~94%之间。该基因编码的蛋白具有6个跨膜结构域、中央孔道结构域、锚定蛋白结构域等AKT基因家族所具有的全部功能结构域,属于AKT家族。蛋白的进化树分析表明:SsAKT1与禾本科植物玉米、粟米、水稻等中的AKT1亲缘关系较近,而与双子叶植物中的AKT1关系较远。实时荧光定量PCR检测低钾、干旱及盐胁迫24h后基因表达的变化显示,SsAKT1基因在三种胁迫下,表达均上调,其中以盐胁迫对该基因表达影响最大。由此可见SsAKT1基因对甘蔗耐低钾、干旱、盐胁迫具有一定的作用。
Potassium channel protein is one of the main ways plants absorb potassium. In this study, the potassium channel protein gene was cloned from low potassium stress sugarcane roots by RT-PCR and named as SsAKT1, with a total length of 3119 bp and an open reading frame of 2658 bp with 885 amino acids. The protein encoded by SsAKT1 gene has high homology with AKT1 gene in other crops, and the proportion of consistent amino acids is between 61% and 94%. The protein encoded by this gene has all the functional domains of the AKT gene family such as six transmembrane domains, central tunnel domain, and anchor protein domain, belonging to the AKT family. Phylogenetic tree analysis showed that SsAKT1 has a close genetic relationship with AKT1 in gramineous plants such as corn, corn and rice, and has a distant relationship with AKT1 in dicotyledons. The changes of gene expression detected by real-time fluorescence quantitative PCR 24h after hypokalemia, drought and salt stress showed that SsAKT1 gene was up-regulated under the three stress conditions, of which the salt stress had the greatest impact on the gene expression. Thus SsAKT1 gene on sugarcane resistance to low potassium, drought, salt stress has a certain role.