剑麻超氧化物歧化酶基因鉴定及低温胁迫表达分析

Identification of Superoxide Dismutase Genes and Expression Analysis Under Cold Stress in Sisal

剑麻是热带地区重要的纤维作物,生产中易受到寒害威胁而造成减产。超氧化物歧化酶(SOD)是一种重要的保护酶,在植物应答低温等逆境条件胁迫过程中起重要作用。前人研究已初步明确超氧化物歧化酶在剑麻低温处理后起重要作用,但其在剑麻中的基因序列及分子调控机制尚未明确。在已发表的剑麻转录组数据库中鉴定出5个SOD基因,遗传进化分析显示其在不同植物物种中进化较保守。实时定量PCR结果显示低温胁迫后5个基因表达模式均呈先上升后下降趋势,且均与SOD活性变化显著正相关(P<0.05)。其中2个CSD基因和1个FSD基因与SOD活性极显著正相关(P<0.01),表明这3个基因在应答低温胁迫过程中起重要作用。研究鉴定了剑麻SOD基因并初步明确其应答低温胁迫表达模式,为深入开展剑麻抗寒机制研究提供了重要基础。

The sisal is an important fiber crop in tropical areas,which is easily threatened by cold stress,resulting in reduced production.Superoxide dismutase(SOD)is an important protective enzyme that plays an important role in plant response to stress conditions including cold stress.Previous studies have preliminarily confirmed the important role of SOD under cold stress in sisal,but few are known about their gene sequences and molecular regulatory mechanisms in sisal.In this study,five SOD genes according to the published sisal transcriptome database,and genetic evolution analysis showed the relatively conserved evolution of SOD genes in different plant species.The real-time quantitative PCR results indicated that the expression of five genes increased and then decreased under cold stress.Their expression patterns were also positively correlated with SOD activity(P<0.05).Among these,two CSD genes and one FSD gene were significantly positive correlated with SOD activity(P<0.01),which indicated their important roles in response to cold stress.This study identified the SOD genes in sisal and preliminarily clarified their expression patterns in response to cold stress,providing an important basis for further researches related to the mechanisms of cold stress response in sisal.