Banzet N, Richaud C, Deveaux Y, Kazmaier M, Gagnon J, Triantaphylidès C
CEA-Cadarache, Département d'Ecophysiologie Végétale et de Microbiologie, Saint-Paul Lez Durance, France.
Plant J. 1998 Feb;13(4):519-27. doi: 10.1046/j.1365-313x.1998.00056.x.
Changes in gene expression, by application of H2O2, O2.- generating agents (methyl viologen, digitonin) and gamma irradiation to tomato suspension cultures, were investigated and compared to the well-described heat shock response. Two-dimensional gel protein mapping analyses gave the first indication that at least small heat shock proteins (smHSP) accumulated in response to application of H2O2 and gamma irradiation, but not to O2.- generating agents. While some proteins seemed to be induced specifically by each treatment, only part of the heat shock response was observed. On the basis of Northern hybridization experiments performed with four heterologous cDNA, corresponding to classes I-IV of pea smHSP, it could be concluded that significant amounts of class I and II smHSP mRNA are induced by H2O2 and by irradiation. Taken together, these results demonstrate that in plants some HSP genes are inducible by oxidative stresses, as in micro-organisms and other eukaryotic cells. HSP22, the main stress protein that accumulates following H2O2 action or gamma irradiation, was also purified. Sequence homology of amino terminal and internal sequences, and immunoreactivity with Chenopodium rubrum mitochondrial smHSP antibody, indicated that the protein belongs to the recently discovered class of plant mitochondrial smHSP. Heat shock or a mild H2O2 pretreatment was also shown to lead to plant cell protection against oxidative injury. Therefore, the synthesis of these stress proteins can be considered as an adaptive mechanism in which mitochondrial protection could be essential.
通过对番茄悬浮培养物施加过氧化氢（H₂O₂）、产超氧阴离子（O₂⁻）试剂（甲基紫精、洋地黄皂苷）和γ射线，研究了基因表达的变化，并与已充分描述的热休克反应进行了比较。二维凝胶蛋白质图谱分析首次表明，至少小热休克蛋白（smHSP）在施加H₂O₂和γ射线后积累，但在施加产O₂⁻试剂后不积累。虽然有些蛋白质似乎是由每种处理特异性诱导的，但只观察到了部分热休克反应。基于用四种与豌豆smHSP的I-IV类相对应的异源cDNA进行的Northern杂交实验，可以得出结论，I类和II类smHSP mRNA的大量表达是由H₂O₂和辐射诱导的。综上所述，这些结果表明，在植物中，一些HSP基因可被氧化应激诱导，这与微生物和其他真核细胞的情况相同。还纯化了在H₂O₂作用或γ射线照射后积累的主要应激蛋白HSP22。氨基末端和内部序列的序列同源性，以及与藜红线粒体smHSP抗体的免疫反应性，表明该蛋白属于最近发现的植物线粒体smHSP类别。热休克或轻度H₂O₂预处理也被证明可导致植物细胞对氧化损伤的保护。因此，这些应激蛋白的合成可被视为一种适应性机制，其中线粒体保护可能至关重要。
