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: ROS1, a repressor of transcriptional gene silencing in Arabidopsis, encodes a DNA glycosylase/lyase.
    Author: Gong Z, Morales-Ruiz T, Ariza RR, Roldán-Arjona T, David L, Zhu JK.
    Journal: Cell; 2002 Dec 13; 111(6):803-14. PubMed ID: 12526807.
    Abstract:
    Mutations in the Arabidopsis ROS1 locus cause transcriptional silencing of a transgene and a homologous endogenous gene. In the ros1 mutants, the promoter of the silenced loci is hypermethylated, which may be triggered by small RNAs produced from the transgene repeats. The transcriptional silencing in ros1 mutants can be released by the ddm1 mutation or the application of the DNA methylation inhibitor 5-aza-2'-deoxycytidine. ROS1 encodes an endonuclease III domain nuclear protein with bifunctional DNA glycosylase/lyase activity against methylated but not unmethylated DNA. The ros1 mutant shows enhanced sensitivity to genotoxic agents methyl methanesulfonate and hydrogen peroxide. We suggest that ROS1 is a DNA repair protein that represses homology-dependent transcriptional gene silencing by demethylating the target promoter DNA.
    [Abstract] [Full Text] [Related] [New Search]