Flagellin peptide flg22 is transported to distal tissues in Arabidopsis.
J. JELENSKA (1), S. Davern (2), R. Standaert (2), S. Mirzadeh (2), J. Greenberg (1) (1) University of Chicago, U.S.A.; (2) Oak Ridge National Laboratory, U.S.A.

Plants often deploy secreted peptide ligands to control defense and developmental responses via receptor kinases. They also respond to pathogen-derived peptides to elaborate both local and systemic defense responses. A key gap in knowledge is the fate of such ligands: whether and by what mechanism they might enter cells and their potential to be mobile in plants. We used biologically active fluorophore and radiolabeled peptides to establish that flg22 is trafficked to distal organs with the closest vascular connections. Remarkably, entry into the plant cell via endocytosis together with the FLS2 receptor is needed for delivery to vascular tissue and long-distance transport of flg22. This contrasts with known routes of long-distance transport of other non-cell permeable molecules in plants, which require membrane-localized transporters for entry to vascular tissue. Thus, a plasma membrane receptor acts as a transporter to enable access of its ligand to distal trafficking routes.

Abstract Number: P17-538
Session Type: Poster