The phytohormone cytokinin plays a major role in plant development. Recently we have reported the identification and comparative analyses of genes associated with cytokinin signaling and homeostasis pathways in two hardwood tree species: Populus trichocarpa and Prunus persica (Immanen et al., 2013). To better understand the role that cytokinin responsive genes play in stone fruit development, we have performed RNA-seq and qPCR analyses of peach fruits treated with exogenously applied t-zeatin at different developmental stages. These analyses reveal a developmental stage specific expression of the cytokinin signaling and homeostasis pathway genes in peach fruits. We have also identified cytokinin responsive genes during pre-lignification, lignification and post-lignification stages of stone-fruit development in Prunus persica. Furthermore, transient overexpression of a putative type-B response regulator (PpRR1) in peach fruits increased the expression of putative downstream genes, PpShy2 and PpRR6. These results suggest that the cytokinin response pathway that has been described in Arabidopsis is conserved in Peach, and that this response pathway is differentially expressed during peach stone-fruit development. This work was funded by CONICYT Fondecyt /Regular N°1121021
