These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: DNA demethylase ROS1 prevents inheritable DREB1A/CBF3 repression by transgene-induced promoter methylation in the Arabidopsis ice1-1 mutant.
    Author: Kim JS, Kidokoro S, Shinozaki K, Yamaguchi-Shinozaki K.
    Journal: Plant Mol Biol; 2020 Dec; 104(6):575-582. PubMed ID: 33000386.
    Abstract:
    In the ros1-defective mutant, DREB1A repression by the transgene-induced promoter methylation of ice1-1 became inheritable across generations even in the absence of the causative transgene NICE1. Transgene silencing (TGS) is a widely observed event during plant bioengineering, which is presented as a gradual decrease in ectopic gene expression across generations and occasionally coupled with endogenous gene silencing based on DNA sequence similarity. TGS is known to be established by guided DNA methylation machinery. However, the machinery underlying gene recovery from TGS has not been fully elucidated. We previously reported that in ice1-1 outcross descendants, the expressional repression and recovery of DREB1A/CBF3 were instantly achieved by a newly discovered NICE1 transgene, instead of the formerly proposed ice1-1 mutation in the ICE1 gene. The plants harboring NICE1 produced small RNAs targeting and causing the DREB1A promoter to be hypermethylated and silenced. To analyze the role of the plant-specific active DNA demethylase REPRESSOR OF SILENCING 1 (ROS1) in instant DREB1A recovery, we propagated the NICE1-segregating population upon ros1 dysfunction and evaluated the gene expression and DNA methylation levels of DREB1A through generations. Our results showed that the epigenetic DREB1A repression was substantially sustained in subsequent generations even without NICE1 and stably inherited across generations. Consistent with the gene expression results, only incomplete DNA methylation removal was detected in the same generations. These results indicate that a novel inheritable epiallele emerged by the ros1 dysfunction. Overall, our study reveals the important role of ROS1 in the inheritability of TGS-associated gene repression.
    [Abstract] [Full Text] [Related] [New Search]