Abstract
Precise modulation of transcription plays a vital role in both development and the response to environment. Temporal activation or repression of specific genes is accompanied via a plethora of transcriptional regulators. However, relatively little is known about how the activities of these proteins are controlled. Recent findings indicate that post-translational modifications fine-tune the function of transcription regulators by affecting their localization, conformation or stability. The plant immune system lends itself particularly well to studies of transcriptional regulators as activation of the immunity is associated with rapid and dramatic reprogramming of the transcriptome. A case study of the plant immune coactivator NPR1, a key regulator of salicylic acid-mediated gene expression, illustrates that transcription regulator activity may be controlled by redox-based modifications of cysteine thiols, phosphorylation, and ubiquitinylation coupled to protein degradation. Importantly, cross-talk between distinct protein modifications may determine the spatial and temporal activity of transcription regulators that in turn profile the cellular transcriptome.
