Delving deeper into the link between sugar transport, sugar signaling, and vascular system development.

Abstract

Plant growth and development rely on the transport and use of sugars produced during photosynthesis. Sugars have a dual function as nutrients and signal molecules in the cell. Many factors maintaining sugar homeostasis and signaling are now identified, but our understanding of the mechanisms involved in coordinating intracellular and intercellular sugar translocation is still limited. We also know little about the interplay between sugar transport and signaling and the formation of the vascular system, which controls long-distance sugar translocation. Sugar signaling has been proposed to play a role; however, evidence to support this hypothesis is still limited. Here, we exploited recent transcriptomics datasets produced in aerial organs of Arabidopsis to identify genes coding for sugar transporters or signaling components expressed in the vascular cells. We identified genes belonging to sugar transport and signaling for which no information is available regarding a role in vasculature development. In addition, the transcriptomics datasets obtained from sugar-treated Arabidopsis seedlings were used to assess the sugar-responsiveness of known genes involved in vascular differentiation. Interestingly, several key regulators of vascular development were found to be regulated by either sucrose or glucose. Especially CLE41, which controls the procambial cell fate, was oppositely regulated by sucrose or glucose in these datasets. Even if more experimental data are necessary to confirm these findings, this survey supports a link between sugar transport/signaling and vascular system development.