Alterations in the transcriptome and translatome profiles of Arabidopsis pollen germinated under heat stress

Plant reproduction is one key biological process very sensitive to heat stress and, as a consequence, enhanced global warming imposes serious threats to sustain food safety worldwide. In this work we have focused on the molecular impact that high temperature conditions impose on gene expression of Arabidopsis pollen germinated in vitro. We have used a high-resolution ribosome profiling technology to provide, for the first time, a comprehensive study of how both the transcriptome and the translatome of germinated pollen respond to the increase in temperature. Although heat shock responses operate properly under high temperature conditions, we have uncovered important alterations under elevated temperature regimes down-regulating essential processes linked to cation/proton exchange and to carbohydrate/cation symport transport. These alterations provide molecular explanations to the dramatic alterations of pollen tube growth under heat stress. Overall a high correlation between transcriptional and translational responses to high temperature was found, but specific regulations at the translational level are also present in pollen subjected to temperature challenging conditions. Overall design: Riboprofiling analysis was performed for Arabidopsis thaliana in vitro germinated pollen at permissive and restrictive temperatures (24°C 35°C respectively).