拟南芥AtOHRP1在氧化胁迫应答中的功能初探

C3HC4 RING finger结构在植物非生物胁迫应答中发挥着重要作用。在对拟南芥基因组进行生物信息学分析过程中发现，NP_195772.1含有一个C3HC4 RING finger保守结构域。基因表达分析显示该基因受H2O2显著诱导。其突变体对高光、过氧化氢、高盐以及黑暗等胁迫高度敏感，叶片白化现象显著，相对叶绿素含量较于野生型也有明显降低，故将其命名为AtOHRP1(Arabidopsis thaliana Oxidative Hypersensitive RING Finger Protein 1)。通过分析氧化胁迫后植物体内过氧化氢的含量及抗氧化酶活性的变化，发现突变体体内有更多过氧化氢的积累且活性氧清除系统中关键酶，超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)活性比野生型降低明显。表明AtOHRP1在氧化胁迫等非生物胁迫过程中发挥着重要的生理功能。

First Exploration on Function of Arabidopsis AtOHRP1 in Response to Oxidative Stress

The motif of C3HC4 RING finger has been reported to play important roles in abiotic stress. According to bio\|informatic analysis, we noticed an unknown function protein (NP_568885.1) in Arabidopsis, containing a conserved C3HC4 RING finger domain. Expression profile showed that the gene was dominantly accumulated in plant old tissues and significantly induced by hydrogen peroxide. Phenotypic analysis showed that the mutant exhibited hypersensitive to NaCl, H2O2, high light and dark treatment. Thereby, we named it AtOHRP1 (Arabidopsis thaliana Oxidative Hypersensitive RING Finger Protein 1). Accordantly, decreased chlorophyll content and increased level of hydrogen peroxide production were detected in atohrp1, and reduced activity of antioxidant enzymes including Superoxide Dismutase (SOD), Catalase (CAT) and Ascorbate Peroxidase (APX), was distinct, compared with those in wild\|type plants. All of these results suggested that RING Finger Protein AtOHRP1 may play an important physiological role in oxidative stress process.