Submitted to: International Congress on Molecular Plant-Microbe Interactions
Publication Type: Proceedings
Publication Acceptance Date: 3/3/2009
Publication Date: 3/1/2010
Citation: Wang, J., Replogle, A., Joshi, S., Korkin, D., Hussey, R., Baum, T., Davis, E., Wang, X., Mitchum, M.G. 2010. Cellular targeting and host-specific recognition of cyst nematode CLE proteins. International Congress on Molecular Plant-Microbe Interactions. 7:1. Interpretive Summary:
Technical Abstract: Cyst nematodes produce secreted peptide mimics of plant CLAVATA3/ESR (CLE) peptides likely involved in redirecting CLE signaling pathways active in roots to form unique and essential feeding cells. The hallmark structure of plant CLEs, which includes an N-terminal signal peptide, a highly variable domain, and a conserved 14-aa CLE domain at or near the C-terminus, is preserved in nematode CLE proteins. The signal peptide targets plant CLEs to the extracellular space where the preproteins are processed to release bioactive CLE motif peptides of 12-aa or 13-aa. Structure-function studies of nematode CLE proteins determined that the 12-aa CLE motif peptide is required, but not sufficient for function in planta. Similarly, the variable domain of nematode CLE proteins is necessary for their function in the extracellular space in the absence of a signal peptide, implicating a potential role in protein targeting if nematodes secrete CLEs directly to the cytoplasm of parasitized root cells. Site-directed mutagenesis and swapping of the variable domain sequence immediately N-terminal to the conserved CLE domain determined that nematode CLEs are also subject to host-specific recognition. We propose that this domain is important for host-specific CLE peptide processing which may help explain the molecular mechanism controlling host-range specificity of cyst nematodes.