拟南芥神经酰胺酶基因对氧化胁迫的响应

以拟南芥哥伦比亚生态型（Col）和神经酰胺酶突变体为实验材料，通过对突变体的一系列生理生化指标的测定，来研究拟南芥神经酰胺酶基因（AtCER）对H2O2的响应。利用PCR和Northern blot获得了9个AtCER纯合单突变体。不同浓度H2O2处理野生型和突变体后，发现突变体对H2O2的反应比野生型更加敏感。H2O2处理后突变体叶片出现比野生型更严重的黄化现象和坏死斑点，总叶绿素含量也比野生型下降的更快，电导率测定也发现突变体比野生型的电导率增加得更多。抗氧化酶活性的分析结果发现H2O2处理后，突变体的抗氧化酶活性比野生型提高了1．5～3倍。上述研究结果说明AtCER参与了H2O2诱导的氧化胁迫反应。

The Response of AtCER to Oxidative Stress in Arabidopsis thaliana

Ceramide is a second messenger involved in many significant signal pathways of plants, such as cell growth, reduplication, differentiation, seneseence and apoptosis. This work investigated the AtCER function in oxidative stress caused by H2O2. The leaves of AtCER mutants cerl, cer2 and cer3, exhibited more severe levels of yellowing and necrotic lesions than wild-type with H2 02 treatment. Further investigation by the physiological and biochemical methods, indicated that chlorophyll content of these mutants decreased more quickly than do wild type plants, and their conductivity increased significantly, and the antioxidases activity in leaves of AtCER mutants were approximately 1.5 or 3-fold higher than that in wild-type after H2O2 treatment. All of those results suggested that AtCER may involved in H2O2-induced Oxidative stress.