沙蒿PP2C2基因的序列分析及其在干旱胁迫下的表达模式

Sequence analysis of PP2C2 gene in Artemisia desertorum and its expression pattern under drought stress

关键词:  沙蒿, PP2C2基因, 序列分析, 蛋白结构预测, 基因表达

Key words:  Artemisia desertorum, PP2C2 gene, sequence analysis, protein structure prediction, gene expression

摘要:

2C类蛋白磷酸酶(PP2C)在植株生长发育、细胞周期调节、信号传导及应对环境胁迫方面发挥着重要作用。该研究以干旱荒漠地区强耐旱和多功能植物沙蒿(Artemisia desertorum)为试验材料,通过对沙蒿PP2C2基因进行扩增,基于生物信息学分析沙蒿PP2C2基因序列,预测蛋白结构,分析沙蒿PP2C2基因在不同水分胁迫条件下的表达模式及其对沙蒿耐旱的调控作用。结果表明:(1)沙蒿PP2C2基因的开放阅读框(ORF)为1 404 bp,编码467个氨基酸,与小蓬草(Erigeron canadensis)等植物PP2C基因同源性较高。(2)PP2C2蛋白定位于细胞核中,无信号肽,为非分泌蛋白,其二级结构主要由无规则卷曲组成,具有较强的亲水性,无跨膜螺旋区,含多个修饰位点。(3)qRT-PCR结果显示,PP2C2基因表达随着干旱胁迫程度的加剧而变化,整体呈现上调表达的趋势,复水后表达量下调。该研究初步发现PP2C2基因在沙蒿耐旱机制方面发挥的重要作用,为深入解析沙蒿的耐旱机制及潜在的基因工程应用提供了理论参考。

Abstract:

Protein phosphatase 2C(PP2C)play important roles in growth and development, cell cycle regulation, signal transduction, and responses to environmental stress. This study focused on Artemisia desertorum, a highly drought-tolerant and multifunctional plant native to arid desert regions, to investigate the functional role of PP2C2 gene in drought tolerance. Using A. desertorum as the experimental material, the PP2C2 gene was amplified, its sequence was subjected to bioinformatic analysis, and its protein structure was predicted. Additionally, the expression patterns of PP2C2 under various water stress conditions were analyzed, and the regulatory role of the PP2C2 gene in drought stress responses was elucidated. The results were as follows:(1)The PP2C2 gene in A. desertorum contained an open reading frame(ORF)of 1 404 bp, encoding a protein of 467 amino acids. Sequence alignment demonstrated that the gene shared high homology with PP2C genes from other plants, such as Erigeron canadensis.(2)Bioinformatic analysis revealed that the PP2C2 protein was localized in the nucleus, no signal peptide, and was classified as a non-secretory protein. Its secondary structure predominantly consisted of random coils, with strong hydrophilicity, no transmembrane helical region, and multiple potential modification sites.(3)Quantitative real-time PCR(qRT-PCR)analysis showed that the expression of the PP2C2 gene was responsive to varying levels of drought stress. Under drought conditions, its expression exhibited an overall up-regulation trend, while rehydration led to a significant reduction in expression levels. This study preliminarily reveals that the PP2C2 gene plays a significant role in the drought tolerance mechanism of Artemisia desertorum, offering a theoretical reference for further understanding of its drought resistance mechanism and potential application in genetic engineering.