CROSSTALK MOLECULES. “Many of the crosstalk molecules identified to date represent various classes of secreted small proteins or peptides. In particular, the huge family of hundreds of CRPs, which has previously been shown to comprise proteins with essential roles in pathogen defense and symbiosis, has now emerged to contain key signaling factors in angiosperm reproduction.”
http://www.sciencedirect.com/science/article/pii/S1674205214608996