Redox regulation of chromatin remodelling in plants.

Changes in the cellular redox balance that occur during plant responses to unfavourable environmental conditions significantly affect a myriad of redox-sensitive processes, including those that impact on the epigenetic state of the chromatin. Various epigenetic factors, like histone modifying enzymes, chromatin remodelers, and DNA methyltransferases can be targeted by oxidative posttranslational modifications. As their combined action affects the epigenetic regulation of gene expression, they form an integral part of plant responses to (a)biotic stress. Epigenetic changes triggered by unfavourable environmental conditions are intrinsically linked with primary metabolism that supplies intermediates and donors, such acetyl-CoA and S-adenosyl-methionine, that are critical for the epigenetic decoration of histones and DNA. Here, we review the recent advances in our understanding of redox regulation of chromatin remodelling, dynamics of epigenetic marks, and the interplay between epigenetic control of gene expression, redox signalling and primary metabolism within an (a)biotic stress context.

Quantitative Analysis of Posttranslational Modifications of Plant Histones.

Reshaping of the chromatin landscape under oxidative stress is of paramount importance for mounting an effective stress response. Unbiased systemic identification and quantification of histone marks is crucial for understanding the epigenetic component of plant responses to adverse environmental conditions. We describe a detailed method for isolation of plant histones and subsequent bottom-up proteomics approach for characterization of acetylation and methylation status. By performing label-free quantitative mass spectrometry analysis, relative abundances of histone marks can be statistically compared between experimental conditions.