Peptide signaling in Plants PNAS. NoV 6. 2001. voL.98 no 23 In plants, only a few peptide have been identified that act as signaling molecules e In contrast, signaling peptides are major players in all aspects of the life cycle in animals and yeast suggests that signaling mechanisms across the eukaryotic kingdom are fundamentally different.Peptide Signaling in Plants PNAS, Nov. 6, 2001, vol.98 no. 23 • In plants, only a few peptide have been identified that act as signaling molecules. • In contrast, signaling peptides are major players in all aspects of the life cycle in animals and yeast. • suggests that signaling mechanisms across the eukaryotic kingdom are fundamentally different