Unknown,Transcriptomics,Genomics,Proteomics

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Transcription profiling of Arabidopsis transgenics with extra copies of the chalcone synthase (CHS) gene mutated by ems and screened for revertants reveals genes affected by hog1 alleviation of chs silencing

ABSTRACT: As part of an investigation into mechanisms of HDG silencing in Arabidopsis, we have produced transgenic plants containing extra copies of the chalcone synthase (CHS) gene. The CHS gene mediates an early step in the biosynthesis of the purple pigment anthocyanin. The insertion of extra copies of CHS in Arabidopsis caused the gene to be silenced in some plants. Seeds harvested from these CHS-silenced plants were mutated by treatment with ems. The progeny of these seeds were screened for "revertants" in which the effects of CHS silencing was alleviated and plants were able to produce anthocyanin. These revertants were found to contain a single recessive mutation; the trait has been termed hog1 (for homology dependant gene silencing 1). Our previous experiment used the Affymetrix 8200 chip to make comparisons between gene expression in the two genetic variants: the CHS-silenced type (ECG) and the anthocyanin-producing revertants (15B). Results showed that there were over 100 genes with at least a 10-fold increase or decrease in expression. However, the variation between 2 reps of each genetic variant was high. We would now like to carry out a modified version of this experiment using the 25K Affymetrix chip. It is intended to increase the number of reps to 4, and take samples at an earlier stage than previously in order to decrease the effect of developmental spread. To reduce the effects of interplant variability, samples will be generated from total plant tissue from a pool of 10 plants at GS 1.04. RNA will be purified using RNeasy kits from Qiagen. Experiment Overall Design: Number of plants pooled:10 Experiment Overall Design: Biological replicates: 4

ORGANISM(S): Arabidopsis thaliana

SUBMITTER: Nottingham Arabidopsis Stock Centre (NASC)

PROVIDER: E-GEOD-6166 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Transcription profiling of Arabidopsis transgenics with extra copies of the chalcone synthase (CHS) gene mutated by ems and screened for revertants reveals genes affected by hog1 alleviation of chs silencing

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