Convergent energy and stress signaling

Abstract

Plants are constantly confronted by multiple types of stress. Despite their distinct origin and mode of perception, nutrient deprivation and most stresses have an impact on the overall energy status of the plant, leading to convergent downstream responses that include largely overlapping transcriptional patterns. The emerging view is that this transcriptome reprogramming in energy and stress signaling is partly regulated by the evolutionarily conserved energy sensor protein kinases, SNF1 (sucrose non-fermenting 1) in yeast, AMPK (AMP-activated protein kinase) in mammals and SnRK1 (SNF1-related kinase 1) in plants. Upon sensing the energy deficit associated with stress, nutrient deprivation and darkness, SnRK1 triggers extensive transcriptional changes that contribute to restoring homeostasis, promoting cell survival and elaborating longer-term responses for adaptation, growth and development.

Heterodimers of the Arabidopsis Transcription Factors bZIP1 and bZIP53 Reprogram Amino Acid Metabolism during Low Energy Stress

“…When overexpressed, it activates transcription independently of the energy status of the cell, whereas bZIP1 activity is further fine-tuned at the posttranslational level by a starvationdependent signal. Recently, KIN10 and KIN11, two kinases of the SnRK1 family, have been demonstrated to orchestrate starvation responses, in particular on the transcriptional level (BaenaGonzá lez et al, 2007;Baena-Gonzá lez and Sheen, 2008). It remains to be analyzed whether the starvation signal regulating bZIP1 function is directly or indirectly mediated by these kinases.…”

Abiotic stress and the plant circadian clock

“…Intriguingly, the signaling interactions between the metabolic and stress signaling networks centrally require the sucrose non-fermenting-1 (SNF1)-related protein kinases. 90 Whether these kinases participate in integrating abiotic stress signals to the oscillator is not known, but deserves investigation.…”

Differential Anoxic Expression of Sugar-Regulated Genes Reveals Diverse Interactions between Sugar and Anaerobic Signaling Systems in Rice

“…Upon sensing an energy deficit caused by an environmental perturbation(s), plants re-establish homeostasis by down-regulating growth-related energy-consuming processes and promoting nutrient mobilization, defense, acclimation, and ultimately, adaptation. The orchestrated re-allocation of energy use mediated by energy signaling ensures better tolerance of stress, allowing for more successful survival in fluctuating environments (Baena-Gonzalez, 2010;Baena-Gonzalez and Sheen, 2008).…”