Van Camp W, Hérouart D, Willekens H, Takahashi H, Saito K, Van Montagu M, Inzé D
Department of Genetics, Flanders Interuniversity Institute for Biotechnology, Universiteit Gent, Belgium.
Plant Physiol. 1996 Oct;112(2):525-35. doi: 10.1104/pp.112.2.525.
In eukaryotes, manganese superoxide dismutase is a nuclear-encoded protein that scavenges superoxide radicals in the mitochondrial matrix. We have isolated two manganese superoxide dismutase genes from Nicotiana plumbaginifolia L. and fused the 5' upstream regulatory region of these genes to the beta-glucuronidase reporter gene. The two gene fusions displayed a differential tissue specificity in transgenic tobacco (Nicotiana tabacum). Promoter activity of the SodA1 gene fusion was found in the pollen, middle layer, and stomium of anthers, but was usually undetectable in vegetative organs of mature plants. The SodA2 gene fusion was expressed in the leaves, stems, roots, and flowers. SodA2 promoter activity was most prominent in the vascular bundles, stomata, axillary buds, pericycle, stomium, and pollen. Histochemical analysis of succinate dehydrogenase activity suggested that the spatial expression of the two gene fusions is generally correlated with mitochondrial respiratory activity.
在真核生物中，锰超氧化物歧化酶是一种核编码蛋白，可清除线粒体基质中的超氧自由基。我们从白花烟草中分离出两个锰超氧化物歧化酶基因，并将这些基因的5'上游调控区与β-葡萄糖醛酸酶报告基因融合。这两个基因融合体在转基因烟草中表现出不同的组织特异性。SodA1基因融合体的启动子活性在花药的花粉、中层和裂口处被发现，但在成熟植株的营养器官中通常检测不到。SodA2基因融合体在叶、茎、根和花中表达。SodA2启动子活性在维管束、气孔、腋芽、中柱鞘、裂口和花粉中最为显著。琥珀酸脱氢酶活性的组织化学分析表明，这两个基因融合体的空间表达通常与线粒体呼吸活性相关。
