HAESA and HAESA-LIKE2 activate organ abscission downstream of NEVERSHED and EVERSHED in Arabidopsis flower

Abstract

A ligand-receptor module comprised of the peptide inFLorESCEnCE DEFiCiEnt in aBSCiSSion (iDa) and the receptorlike kinases haESa (haE) and haESa-LiKE2 (hSL2) activates organ abscission in Arabidopsis flowers. another set of receptor-like kinases, including EVErShED (EVr), restricts the extent of cell separation in abscission zones by potentially altering haE/hSL2 localization or activity. the nEVErShED (nEV) aDP-ribosylation factor GtPase-activating protein facilitates the intracellular movement of molecules required for organ abscission and fruit growth. here we report further analysis of the relationship between nEV-mediated intracellular traffic, EVr activity and iDa-haE/hSL2 signaling during flower development. our results support a model in which cell separation is mediated by haE/hSL2 signaling downstream of nEV and EVr. We discuss the possibility that conserved circuits control organ abscission and modulate fruit growth. © 2014 Landes Bioscience.