干旱胁迫对木豆叶片的影响及机理验证

Effects of Drought Stress on Cajanus cajan Leaves and Mechanism Verification

以木豆(Cajanus cajan)为研究对象,运用生物信息学方法从木豆的基因组中鉴定基因,对其进行了基本的理化性质预测、系统发育、保守基序、顺式作用元件等分析,同时进行组织特异性分析、过表达植株构建以及生理指标分析。结果表明:从木豆基因组中鉴定得到14个SnRK2家族基因,发现SnRK2氨基酸的数量在217~383之间,相对分子质量为24578.32~43627.79,等电点范围为4.78~9.22;SnRK2基因家族聚集成3个分支,分布均匀;外显子和内含子分布保守,除CcSnRK2.13(8个外显子和7个内含子)和CcSnRK2.14(6个外显子和5个内含子)外,都含有9个外显子以及8个内含子;所有的CcSnRK2基因启动子区域都包含启动子和增强子区、厌氧诱导、光诱导调控、玉米蛋白代谢诱导调控、干旱诱导调控和脱落酸诱导调控元件;CcSnRK2家族成员的二级结构在一定程度上有相似性,每个结构的氨基酸数量占比较为一致;根据基因表达情况以及前面的分析结果,选择CcSnRK2.5、CcSnRK2.8和CcSnRK2.9进行功能验证,发现其在叶片中高表达。CcSnRK2.5、CcSnRK2.8和CcSnRK2.9过表达显著提高了植株的耐旱生存能力,保持较好的叶片形态、水分平衡、细胞膜完整性等,表现出干旱胁迫条件下生理指标的显著改善。从全基因组鉴定了SnRK2基因并表征了其基本特征,通过植物遗传转化发现SnRK2增强了木豆耐旱性。

Using Cajanus cajan as the research subject,bioinformatics methods were employed to identify genes from the C.cajan genome and analyze their basic physicochemical properties,phylogeny,conserved motifs,and cis-acting elements.Tissue-specific analysis,overexpression plant construction,and physiological index analysis were also conducted.The results showed that 14 SnRK2 family genes were identified from the C.cajan genome,with SnRK2 amino acid lengths ranging from 217 to 383,relative molecular weights between 24578.32 and 43627.79,and isoelectric points ranging from 4.78 to 9.22.The SnRK2 gene family clustered into three branches,with uniform distribution.Exon and intron distribution were conserved,with all genes containing 9 exons and 8 introns except for CcSnRK 2.13(8 exons and 7 introns)and CcSnRK 2.14(6 exons and 5 introns).Promoter regions of all CcSnRK 2 genes contained promoter and enhancer regions,anaerobic induction,light-responsive regulation,zein metabolism regulation,drought-induced regulation,and abscisic acid-induced regulation elements.The secondary structure of CcSnRK 2 family members showed a certain degree of similarity,with consistent proportions of amino acids in each structure.Based on gene expression profiles and prior analysis,CcSnRK 2.5,CcSnRK 2.8,and CcSnRK 2.9 were selected for functional verification and were found to be highly expressed in leaves.Overexpression of CcSnRK 2.5,CcSnRK 2.8,and CcSnRK 2.9 significantly enhanced the drought-tolerant survival capability of the plants,maintaining better leaf morphology,water balance,and cell membrane integrity,showing significant improvement in physiological indices under drought stress.SnRK2 genes were identified and characterized from the whole genome,and plant genetic transformation revealed that SnRK2 enhanced drought resistance in C.cajan.