BioProject

We used whole-genome microarrays to identify differentially expressed genes in leaves of GA-deficient (35S::PcGA2ox) and/or GA-insensitive (35S::rgl1) transgenics as compared to WT poplar (717-1B4 genotype). More...

We used whole-genome microarrays to identify differentially expressed genes in leaves of GA-deficient (35S::PcGA2ox) and/or GA-insensitive (35S::rgl1) transgenics as compared to WT poplar (717-1B4 genotype). Our work suggests that the molecular machinery that reduces gibberellins (GAs) concentration and signaling is a major route for restraining growth under both immediate and imminent adverse conditions. We show that inhibition of growth as a result of water deprivation and short days (SDs) coincides with up-regulation of several DELLA and GA2ox encoding genes in poplar. Likewise, GA-deficient and GA-insensitive transgenics, with up-regulated GA2ox and DELLA domain proteins, elicited a hypersensitive growth inhibition in response to both drought and SDs. Because the GA-modified transgenic showed accelerated response to drought and SD, we hypothesized that the mechanisms associated with these responses are constitutively elevated even under control conditions (well-watered, long day photoperiod). Therefore, we used whole-genome poplar microarray to study transcriptome level changes in the leaves of transgenic compared to WT plants grown under control environment. Overall design: Genetic background for all plants was INRA 717-1B clone (Populus tremula x Populus alba). Expression analysis was preformed on three individual genotypes; wild-type (WT, untransformed control), 35S::PcGA2ox and 35S::rgl1. Leaves from two independent biological replicates per genotype were used, each pooled from 20 clonally propagated plants. Less...