The arabidopsis GyraseB3 contributes to transposon silencing by promoting histone deacetylation.

ABSTRACT: DNA methylation and histone modifications are key epigenetic marks controlling chromatin structure, gene expression, and transposable element (TE) activity. In plants, the histone demethylase INCREASE IN BONSAI METHYLATION1 (IBM1) prevents heterochromatic silencing marks from accumulating on actively transcribed genes. Through a genetic screen of mutants defective in IBM1 production, we identified suppressor mutations in genes essential for maintaining balanced genome-wide epigenetic states. The gyrb3 mutation partly reversed DNA hypermethylation in IBM1-deficient plants, revealing a novel role for GyrB3, a nuclear protein combining domains from cyanobacterial gyrases and ELM2/SANT proteins involved in histone acetylation. In gyrb3 mutants, TEs exhibit transcriptional activity, showing red

SUBMITTER: Gy I 

PROVIDER: S-EPMC12489469 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature