Developmental Defects Mediated by the P1/HC-Pro Potyviral Silencing Suppressor Are Not Due to Misregulation of AUXIN RESPONSE FACTOR 8
| Autor: | Vicki S. Vance, Gail J. Pruss, John L. MacArthur, Jason W. Reed, Sizolwenkosi Mlotshwa |
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| Rok vydání: | 2016 |
| Předmět: |
DNA
Bacterial 0301 basic medicine Physiology Transgene Potyvirus Mutant Arabidopsis Plant Science Biology medicine.disease_cause Viral Proteins 03 medical and health sciences Gene Expression Regulation Plant RNA interference Genetics medicine Point Mutation Gene silencing Arabidopsis thaliana Genes Suppressor Promoter Regions Genetic Crosses Genetic Regulation of gene expression Mutation Arabidopsis Proteins Articles biology.organism_classification DNA-Binding Proteins Cysteine Endopeptidases Mutagenesis Insertional RNA silencing Phenotype 030104 developmental biology RNA Interference |
| Zdroj: | Plant Physiology. 172:1853-1861 |
| ISSN: | 1532-2548 0032-0889 |
| Popis: | Plant viral suppressors of RNA silencing induce developmental defects similar to those caused by mutations in genes involved in the microRNA pathway. A recent report has attributed viral suppressor-mediated developmental defects to up-regulation of AUXIN RESPONSE FACTOR 8 (ARF8), a target of miR167. The key piece of evidence was that the developmental defects in transgenic Arabidopsis (Arabidopsis thaliana) expressing viral suppressors were greatly alleviated in the F1 progeny of a cross with plants carrying the arf8-6 mutation. Arf8-6 is a SALK line T-DNA insertion mutant, a class of mutations prone to inducing transcriptional silencing of transgenes expressed from the 35S promoter. We have reinvestigated the role of ARF8 in viral suppressor-mediated developmental defects, using two independent arf8 mutations and the P1/HC-Pro potyviral suppressor of silencing. Progeny of a cross between P1/HC-Pro transgenic Arabidopsis and the arf8-6 T-DNA insertion mutant showed little effect on the P1/HC-Pro phenotype in the F1 generation, but almost all arf8-6/P1/HC-Pro progeny had lost the phenotype in the F2 generation. However, the loss of phenotype in the F2 generation was not correlated with the number of functional copies of the ARF8 gene. Instead, it reflected transcriptional silencing of the P1/HC-Pro transgene, as evidenced by a pronounced decrease in P1/HC-Pro mRNA and the appearance of 35S promoter small interfering RNAs. Furthermore, an independent loss-of-function point mutation, Arf8-8, had no detectable effects on P1/HC-Pro phenotype in either the F1 or F2 generations. Together, these data argue against the previously reported role of increased ARF8 expression in developmental defects caused by P1/HC-Pro. |
| Databáze: | OpenAIRE |
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