Transcriptome analysis in pea allows to distinguish chilling and acclimation mechanisms

In order to distinguish chilling and freezing tolerance mechanisms in pea, responses to cold exposure were compared between the freezing tolerant line Champagne and the sensitive line Terese. Global gene expression was considered in the two lines and associated with morphological, histological and biochemical approaches. The chilling tolerance in both lines was related to responses of the CBF, COR and LEA genes belonging to the CBF regulon, with greater earliness of expression in the Champagne genotype. The freezing tolerance, only observed in Champagne, was associated with acclimation processes such as cellular osmotic stabilization, photosynthesis modifications, antioxidants production, modifications in hormone metabolism, cell wall composition and dynamics.