Arabidopsis eIF2α kinase GCN2 is essential for growth in stress conditions and is activated by wounding
- Equal contributors
1 Université de Perpignan Via Domitia, CNRS-IRD UMR5096 LGDP, 52 avenue Paul Alduy 66860 Perpignan Cedex, France
2 Université Luminy, CNRS-CEA UMR6191 LGBP, 13009 Marseille Cedex 9, France
3 Université Blaise Pascal, GReD UMR CNRS 6247, 24 Avenue des Landais, 63177 Aubière, France
BMC Plant Biology 2008, 8:134 doi:10.1186/1471-2229-8-134Published: 24 December 2008
Phosphorylation of eIF2α provides a key mechanism for down-regulating protein synthesis in response to nutrient starvation or stresses in mammalian and yeast cells. However, this process has not been well characterized in plants
We show here that in response to amino acid and purine starvations, UV, cold shock and wounding, the Arabidopsis GCN2 kinase (AtGCN2) is activated and phosphorylates eIF2α. We show that AtGCN2 is essential for plant growth in stress situations and that its activity results in a strong reduction in global protein synthesis.
Our results suggest that a general amino acid control response is conserved between yeast and plants but that the plant enzyme evolved to fulfill a more general function as an upstream sensor and regulator of diverse stress-response pathways. The activation of AtGCN2 following wounding or exposure to methyl jasmonate, the ethylene precursor 1-Aminocyclopropane-1-carboxylic acid (ACC) and salicylic acid, further suggests that this enzyme could play a role in plant defense against insect herbivores.