Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Suppressing the barley uroporphyrinogen gene by Ds activation tagging element generates developmental photosensitivity

ABSTRACT: Chlorophyll production involves the synthesis of photoreactive intermediates that are toxic when in excess due to the production of reactive oxygen species (ROS). A novel activation tagged barley mutant is described that results from antisense suppression of a uroporphyrinogen III synthase (Uros) gene, the product of which catalyses the sixth step in the synthesis of chlorophyll and heme. In homozygous mutant plants uroporphyrin(ogen) I accumulates by spontaneous cyclization of hydroxyl methylbilane, the substrate of Uros. Accumulation of this tetrapyrrole intermediate results in photosensitive cell death due to the production of reactive oxygen species. The efficiency of Uros gene suppression is developmentally regulated, being most effective in mature seedling leaves compared with newly emergent leaves. A comparison of RNA from mutant and wild type seedlings grown under 30% and 3% light, shows reduced transcript accumulation of a number of nuclear-encoded photosynthesis genes occurs in the mutant even under 3% light conditions. This is consistent with a retrograde plastid-nuclear signalling mechanism arising from Uros gene suppression. No evidence for a direct signalling role by uroporphyrin I was observed suggesting that nuclear gene transcriptional suppression was mediated by ROS accumulation. Two replicates samples were used for barley mutant 70a3 grown under 3% and 2 replicate sample of the mutant grown under 30% light, barley cv Golden Promise was used as the control.

ORGANISM(S): Hordeum vulgare

SUBMITTER: Andrew Spriggs

PROVIDER: E-GEOD-11776 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Suppression of the barley uroporphyrinogen III synthase gene by a Ds activation tagging element generates developmental photosensitivity.

Ayliffe Michael A MA Agostino Anthony A Clarke Bryan C BC Furbank Robert R von Caemmerer Susanne S Pryor Anthony J AJ

The Plant cell 20090331 3

Chlorophyll production involves the synthesis of photoreactive intermediates that, when in excess, are toxic due to the production of reactive oxygen species (ROS). A novel, activation-tagged barley (Hordeum vulgare) mutant is described that results from antisense suppression of a uroporphyrinogen III synthase (Uros) gene, the product of which catalyzes the sixth step in the synthesis of chlorophyll and heme. In homozygous mutant plants, uroporphyrin(ogen) I accumulates by spontaneous cyclizatio ...[more]

PMID: 19336693

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Dataset Information

Suppressing the barley uroporphyrinogen gene by Ds activation tagging element generates developmental photosensitivity

Publications

Suppression of the barley uroporphyrinogen III synthase gene by a Ds activation tagging element generates developmental photosensitivity.

Similar Datasets

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