DNA Damage Response Mechanisms in Plants

Plants constantly face threats to genome integrity arising from both internal processes such as replication stress and reactive metabolic by-products, and external challenges including ultraviolet radiation, chemical mutagens and pathogen attack. To maintain genome stability, a conserved network of DNA damage response (DDR) pathways detects lesions, transduces signals and mobilises repair factors while coordinating cell cycle progression and developmental programmes. Central to this system are sensor kinases, notably ATM (Ataxia Telangiectasia Mutated) and ATR (ATM and Rad3-related), which recognise double-strand breaks and stalled forks respectively. Activated kinases phosphorylate downstream effectors, including the plant-specific transcription factor SOG1 (Suppressor of Gamma Response 1), to initiate cell cycle arrest, transcriptional reprogramming and repair pathway choice. Double-strand breaks are mended through homologous recombination, using sister chromatids as templates, or by non-homologous end joining, which ligates broken ends with minimal homology. Additional pathways such as base excision repair and nucleotide excision repair attend to single-base lesions and helix-distorting damage. Chromatin modifications, including histone methylation and acetylation, modulate accessibility of repair proteins and integrate stress signals into epigenetic memory. This multilayered response underpins meristem maintenance, stress tolerance and developmental plasticity in sessile plants, with direct implications for crop improvement and resilience to environmental change.

Research from Nature Portfolio

Recent studies have revealed that loss of the heterochromatic histone mark H3.1K27me1, deposited by ATXR5 and ATXR6 methyltransferases, confers robust resistance to Geminivirus infection in Arabidopsis. In mutants lacking H3.1K27me1, DNA repair proteins RAD51 and RPA1A are redirected from viral DNA to host heterochromatin and defence gene loci, reducing viral replication. This redistribution depends on BRCA1, HOP2 and CYCB1;1, which facilitate RAD51 recruitment, and illustrates how chromatin instability can be harnessed to bolster antiviral immunity by sequestering repair machinery away from invading genomes.

DNA Damage Response Mechanisms in Plants publication trend

The graph below shows the total number of articles in dna damage response mechanisms in plants across all publications each year (not limited to Nature Index journals).

Technical terms

ATM: Protein kinase that senses DNA double-strand breaks and activates repair signalling.

ATR: Protein kinase that recognises stalled replication forks and coordinates checkpoint responses.

SOG1: Plant-specific transcription factor that orchestrates DNA damage–induced gene expression and cell cycle arrest.

Homologous recombination (HR): Error-free repair pathway using a homologous DNA template to accurately restore double-strand breaks.

Non-homologous end joining (NHEJ): Repair pathway that ligates broken DNA ends without a homologous template, often with minor sequence alterations.

H3.1K27me1: Monomethylation of lysine 27 on histone H3 variant 1, a chromatin mark associated with heterochromatin stability.

References

1. Distinctive and complementary roles of E2F transcription factors during plant replication stress responses. Molecular Plant (2023).
2. H3.1K27me1 loss confers Arabidopsis resistance to Geminivirus by sequestering DNA repair proteins onto host genome. Nature Communications (2023).
3. Engineered gamma radiation phytosensors for environmental monitoring. Plant Biotechnology Journal (2023).
4. SOG1: a master regulator of the DNA damage response in plants. Genes & Genetic Systems (2015).