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Reduction of coproporphyrinogen oxidase level by antisense RNA synthesis leads to deregulated gene expression of plastid proteins and affects the oxidative defense system.

1995; Springer Nature; Volume: 14; Issue: 15 Linguagem: Inglês

10.1002/j.1460-2075.1995.tb00041.x

1460-2075

Elisabeth Kruse, Hans‐Peter Mock, Bernhard Grimm,

Polyamine Metabolism and Applications

Research Article1 August 1995free access Reduction of coproporphyrinogen oxidase level by antisense RNA synthesis leads to deregulated gene expression of plastid proteins and affects the oxidative defense system. E. Kruse E. Kruse Institut für Pflanzengenetik und Kulturpflanzenforschung, Gatersleben, Germany. Search for more papers by this author H. P. Mock H. P. Mock Institut für Pflanzengenetik und Kulturpflanzenforschung, Gatersleben, Germany. Search for more papers by this author B. Grimm B. Grimm Institut für Pflanzengenetik und Kulturpflanzenforschung, Gatersleben, Germany. Search for more papers by this author E. Kruse E. Kruse Institut für Pflanzengenetik und Kulturpflanzenforschung, Gatersleben, Germany. Search for more papers by this author H. P. Mock H. P. Mock Institut für Pflanzengenetik und Kulturpflanzenforschung, Gatersleben, Germany. Search for more papers by this author B. Grimm B. Grimm Institut für Pflanzengenetik und Kulturpflanzenforschung, Gatersleben, Germany. Search for more papers by this author Author Information E. Kruse1, H. P. Mock1 and B. Grimm1 1Institut für Pflanzengenetik und Kulturpflanzenforschung, Gatersleben, Germany. The EMBO Journal (1995)14:3712-3720https://doi.org/10.1002/j.1460-2075.1995.tb00041.x PDFDownload PDF of article text and main figures. ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InMendeleyWechatReddit Figures & Info A full-length cDNA sequence encoding coproporphyrinogen oxidase was inserted in inverse orientation behind a CaMV promoter and transferred to tobacco (Nicotiana tabacum) by standard transformation techniques. Transformants showed reduced coproporphyrinogen oxidase activity and accumulation of photosensitive coproporphyrin(ogen), indicating antisense RNA expression. An inverse correlation was observed between the level of coproporphyrinogen oxidase and transformant phenotype. The latter is characterized by a broad range of growth retardation and necrosis, indicating oxidative leaf damage. Coproporphyrinogen is an apparent chromophore and its excitation finally leads to the production of reactive oxygen. Evidence is presented that indicates a direct correlation between the accumulation of non-metabolized coproporphyrinogen and oxidative damage to cellular structural components. Enzymatic and non-enzymatic antioxidants were investigated. Whereas superoxide dismutase activity increased in transgenic plants, catalase and ascorbate peroxidase activity remained constant. Tocopherol, rather than carotene or zeaxanthin, seemed to be involved in detoxification, indicating the putative localization and allocation of coproporphyrinogen. Expression of coproporphyrinogen oxidase antisense RNA did not significantly influence the level of other enzymes in the chlorophyll metabolic pathway, but deregulated gene expression of nuclear encoded plastid proteins. Accumulation of coproporphyrinogen and/or the resulting effects, such as oxidative stress, impairs a plastid/nuclear signal which may adapt gene expression to the plastid state. Previous ArticleNext Article Volume 14Issue 151 August 1995In this issue RelatedDetailsLoading ...