干旱胁迫下沙棘脯氨酸含量及HrP5CS基因表达分析  

Analysis of proline content and HrP5CS gene expression in Hippophae rhamnoides under drought stress

作　　者：刘瑞 王晨兆 马玉花[1] LIU Rui;WANG Chenzhao;MA Yuhua(College of Agriculture and Husbandry,Qinghai University,Xining,Qinghai 810016,China)

机构地区：[1]青海大学农牧学院,青海西宁810016

出　　处：《福建农林大学学报（自然科学版）》2023年第6期846-852,共7页Journal of Fujian Agriculture and Forestry University:Natural Science Edition

摘　　要：筛选中国沙棘全长转录组数据中差异表达的HrP5CS基因,对其进行生物信息学分析和不同胁迫下各部位表达模式的研究,同时测量叶中脯氨酸的含量。结果表明:HrP5CS基因全长为2127 bp,编码708个氨基酸,不含信号肽,无跨膜结构的稳定疏水蛋白。与30个同源序列比对表明,氨基酸长度、理论等电点和分子质量相近;聚类分析表明,P5CS蛋白存在明显科属特性,在同科不同属内亲缘性较近;多重序列比较中,中国沙棘HrP5CS与酸枣(Ziziphus jujuba var.spinosa)亲缘性最近且序列一致性最高。荧光定量结果表明,HrP5CS基因在中国沙棘各部位特异性表达,在根和叶中总体呈上升状态,复水后下降至正常水平,在茎中第2天达到最高值后持续下降至最低值,复水后回到正常水平。脯氨酸含量随着干旱胁迫时间的持续呈阶梯式上升趋势,SPSS皮尔森相关系数分析表明,根和茎中的HrP5CS基因表达量与叶中脯氨酸含量呈正相关关系,而在叶中则呈负相关关系。以上结果说明HrP5CS基因表达和脯氨酸的积累对中国沙棘抗旱具有重要意义。The HrP5CS gene expressed differentially under drought stress was screened based on the full-length transcriptome data of Hippophae rhamnoides for bioinformatic analysis,and its expression pattern in different parts of H.rhamnoides was studied under different levels of drought stress.The variation trend of proline content in leaves was further monitored.The results showed that the HrP5CS gene was 2127 bp in length,and encoded a stable hydrophobic protein which contained 708 amino acids without signal peptide and transmembrane structure.Cluster analysis revealled obvious family-and genus-specific characteristis and close relations between different genera within single family.HrP5CS is most closely related to that of Ziziphus jujuba var.spinosa by multiple sequence alignment and shared similar length,theoretical isoelectric point and molecular weight with other 30 homologous proteins.The qRT-PCR results showed that the HrP5CS gene was specifically expressed in all parts of H.rhamnoides.Its expression in root and leave increased with drought treatment but decreased to the normal level after rehydration,while that in stem reached the maximum on day 2 after drought stress and started to decrease the minimum but return to the normality after rehydration.The proline content in leaves was increased steppedly with drought treatment time.SPSS Pearson correlation coefficient analysis revealed that the proline content in leaves was positively correlated with the expression of HrP5CS gene in roots and stems,but negatively correlated with that in leaves.The results above indicated that the expression of HrP5CS gene and accumulation of proline played important roles for the drought resistance of H.rhamnoides.

关 键 词：HrP5CS基因 干旱胁迫 中国沙棘 基因表达 脯氨酸 

分 类 号：Q786[生物学—分子生物学]