Wang, Jianying , Replogle, Amy , Wang, Xiaohong , Davis, Eric , Mitchum, Melissa .
Functional characterization of plant-parasitic cyst nematode CLE peptides.
During infection by plant-parasitic cyst nematodes, proteins produced exclusively in the esophageal gland cells are secreted into a plant cell near the vasculature of the host root to form an enlarged, multinucleate feeding site (syncytium). Soybean cyst nematode (SCN; Heterodera glycines) genes coding for secreted CLAVATA3/ESR(CLE)-like signaling peptides were identified. CLV3, the founding member of a 31 member CLE peptide family in Arabidopsis, plays a role in controlling the balance between shoot meristem cell proliferation and differentiation by signaling through the CLAVATA1(CLV1)/CLAVATA2(CLV2) receptor complex. Two predominant SCN CLE forms, HgCLEA and HgCLEB, share an identical CLE domain and are highly induced at the onset of parasitism. Constitutive overexpression of HgCLEA, not HgCLEB in Arabidopsis results in shoot and floral meristem defects similar to that of overexpression of CLV3, and the severity of the phenotype correlates with the expression level of the transgene. Roots of HgCLEA overexpression lines exhibit premature termination of the primary root meristem. Similarly, exogenous application of a synthetic peptide corresponding to the CLE motif of HgCLE to Arabidopsis and soybean suppresses the growth of primary roots. Homologous sequences with unique CLE domains have been identified from the sugar beet cyst nematode (H. schachtii), a close relative of SCN that can successfully infect Arabidopsis. Overexpression of HsCLEs in Arabidopsis results in more severe phenotypes than that of HgCLEs. These studies provide further evidence that nematode CLEs may play a key role to developmentally reprogram the fate of selected plant cells for syncytium development by ligand mimicry of plant signaling peptides.
Log in to add this item to your schedule
1 - University of Missouri-Columbia, Divison of Plant Sciences and Bond Life Sciences Center, 315, Life Sciences Center, 1201, Rollins St, Columbia, MO, 65211, USA
2 - University of Missouri-Columbia, Divison of Plant Sciences and Bond Life Sciences Center
3 - USDA-ARS, Cornell University, Department of Plant Pathology
4 - North Carolina State University, Department of Plant Pathology
Presentation Type: Plant Biology Abstract
Location: Exhibit Hall (Northeast, Southwest & Southeast)/Hilton
Date: Sunday, July 8th, 2007
Time: 8:00 AM