Study of poplar shoot apex methylome response to variations in soil water avaialbility. Populus x canadensis

In a context of climate changes, water availability is expected to become a limiting factor for plant growth and to have an impact on forest health. In order to identify genes involved in shoot phenotypic plasticity in response to variations in water availability in trees, DNA methylation patterns were investigated in the shoot apical meristem (SAM) of Populus deltoides × P. nigra hybrid cuttings submitted to a moderate water deficit followed by a rewatering step. Transcriptomic response was also studied and is another GEO submission. Overall design: Populus deltoides × P. nigra 'Carpaccio' hybrid cuttings were submitted to 3 water conditions: non-limiting, water deficit and water deficit/rewatering cycle (14 days treatment). At the end of the experiment, buds were collected and SAM maually isolated for 6 individuals per condition. DNA was extracted from 3 individuals per condition and pooled. For each condition, methylated DNA was isolated using a MethylDNA Immunoprecipitation (MeDIP) and both total DNA and MeDIP fraction were hybridised to microarrays.