Poplar acetylome profiling reveals lysine acetylation dynamics in seasonal dormancy release.

Bud dormancy in perennials in boreal and temperate ecosystems is crucial for survival in harsh winter. Dormancy is released by prolonged exposure to low temperatures and is followed by reactive growth in the spring. Lysine acetylation (Kac) is one of the major post-translational modifications (PTMs) involved in plant response to environment signals. However, little information is available on the effects of Kac modification on bud dormancy release. Here, we report the dynamics of lysine acetylome in hybrid poplar (Populus tremula x alba) dormant buds. A total number of 7,594 acetyl sites from 3,281 acetyl proteins were identified, representing the largest to date dataset of lysine acetylome in plants. Of them, 229 proteins were differentially acetylated during bud dormancy release and were involved mainly in the primary metabolism. Site-directed mutagenesis enzymatic assays showed that acetylation strongly modified the activities of two key enzymes of primary metabolism, pyruvate dehydrogenase (PDH) and isocitrate dehydrogenase (IDH). We thus propose that Kac of enzymes could be an important strategy for reconfiguration of metabolic processes during bud dormancy release. In all, our results reveal the importance of Kac in bud dormancy release and give a new perspective to understand the molecular mechanisms of tree’s seasonal growth.