Differential gene expression in Eucalyptus polyploids cultivated in high temperature and elevated CO 2

ABSTRACT: Polyploidy is an event that culminates with the condition of having two or more pairs of homologous chromosomes. Here we used proteomics to unveil the differential gene expression in Eucalyptus urophylla x Eucalyptus grandis polyploids, and its isogenic diploid, when plants were challenged against high temperature and elevated CO2 concentration. Growth under high temperature induced an increase in the leaf area, a phenotypic pattern further increased when plants were cultivated in both high temperature and elevated CO2, but inversely for stem branching. Global proteome analysis indicated the absence of a clear pattern of proteome similarities between genotypes, suggesting a unique differential genome regulation would only occur upon environmental stimulus. We concluded that the polyploidy effects in Eucalyptus genotypes are mostly revealed when influenced by environment, that the proteome responses are genotype dependent and that the changes in the gene expression are more pronounced when plants are cultivated in high temperature.