A cross-species analysis reveals limited translatome conservation at cell type resolution

GERMAIN PAULUZZI; LIDOR SHAAR-MOSHE; JOEL RODRIGUEZ-MEDINA; REYNOSO MAURICIO ALBERTO; BAILEY-SERRES JULIA; DEAL, ROGER B.; BRADY, SIOBHAN M.; KAISA KAJALA; ALEX CANTO-PASTOR; NEELIMA SINHA

Conferencia; Plant Biology 2019; 2019

Plant roots are comprised of different cell types that undergo spatiotemporal changes from meristematic tissues to fully differentiated and specialized cell types. Several transcriptional networks that tightly regulate the developmental trajectories of specific cell types within the root have been elucidated (e.g. trichoblast, endodermis and xylem cells). Yet, our understanding of the evolutionary conservation of these processes is scarce. To this end we developed and exploited a set of cell type- and tissue-specific promoters in Solanum lycopersicum (tomato), Oryza sativa (rice) and Arabidopsis thaliana that enable TRAP (Translating Ribosome Affinity Purification). Using these, we have analyzed the translational landscape of four comparable cell types across these divergent species. In some tissue, gene expression data is more conserved within comparable cell types than between species. We next focused on specific sets of genes that show enriched expression in each cell type. The identity of the cell type-enriched genes (i.e. orthologs), were only partially overlapping across species. Furthermore, enriched biological processes of these gene sets showed limited commonalities within comparable cell types. These analyses indicate that at the level of the translatome, cell type-enriched genes are for the most part species-specific with partial functional conservation across species.