Epigenetic mechanisms controlling peach bud dormancy and its release: preliminary results

Bud dormancy regulation represents a fundamental process for perennial plant survival. Recent findings highlight the importance of epigenetic regulation of dormancy events, and more specifically of chromatin regulation of DAM-related genes in flower buds of Rosaceae. The main goal of this work is to improve our knowledge on the genetic and epigenetic mechanisms during the dormancy and its release in peach buds. During the dormancy, buds were sampled from peach trees (P. persica [L.] Batsch) 'Fantasia' and SR mutant. To investigate bud dormancy at genetic level we analyzed the expression profile of DAM genes in both genotypes to identify the most informative time points in which to perform an extensive analysis of transcriptome by RNA-Seq. At the beginning of the dormancy the expression of DAM4 and DAM6 increases and concurrently the fulfillment of chilling requirement the abundance of their corresponding mRNAs sharply decreased in both vegetative and flower buds. The transcriptome analysis showed a total of 2.470 unique DEGs by comparing the SR and FAN buds, among which genes involved in histone (H3) methylation are present.