Molecular control of dormancy transitions throughout the year in the monoecious cork oak
Bud dormancy plays a vital role in flowering regulation and fruit production, being highly regulated by endogenous and environmental cues. Deployment of epigenetic modifications and differential gene expression control bud dormancy/break cycles. Information on how these genetic and epigenetic mechanisms are regulated throughout the year is still scarce for temperate trees, such as Quercus suber. Here, the expression levels of QsCENL and QsDYL1 during different seasonal cycles of bud development suggest that QsCENL may be implicated in the establishment of growth cessation in Q. suber and that QsDYL1 is a good dormancy marker. Moreover, the analysis of the profiles of epigenetic marks and the expression of modifiers, in dormant versus non-dormant bud meristems, indicate that epigenetic regulation is implicated in how bud development progresses in Q. suber. The identification of bud specific mechanisms opens new possibilities to understand how trees respond to challenging environmental signals derived from climate change.