|Lu, Shunwen - CORNELL UNIVERSITY|
Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: May 18, 2006
Publication Date: August 1, 2006
Citation: Lu, S., Wang, X. 2006. A new class of CLAVATA3/ESR(CLE)-like peptides expressed in the esophageal gland cells of the potato cyst nematode Globodera rostochiensis [abstract]. Phytopathology. 96:S70. Technical Abstract: Plant CLAVATA3/ESR (CLE) proteins are a family of secreted peptide ligands that play important roles in plant growth and development. We have cloned two CLE-like genes, GrCLE1 and GrCLE2, from the potato cyst nematode Globodera rostochiensis, a quarantine pest that threatens the potato industry of the United States. GrCLE1 and GrCLE2 encode putative secretory peptides that contain C-terminal CLE motifs shared with the plant CLE family. Interestingly, unlike most plant CLEs and the newly identified CLEs from cyst nematodes of the genus Heterodera, GrCLE1 and GrCLE2 contain tandem CLE motif repeats with 3 in GrCLE1 and 5 in GrCLE2. In addition, sequence variation exists among these tandem CLE motifs within individual proteins. In situ mRNA hybridization has confirmed the expression of GrCLE1 in the esophageal gland cells. RT-PCR analysis has revealed that GrCLE genes are expressed in both preparasitic and parasitic nematode life stages but they have different expression patterns. Exogenous application of a synthetic peptide corresponding to the GrCLE1 CLE domain to the roots of Arabidopsis, tomato and potato causes a short root phenotype, suggesting functional sufficiency of the nematode CLE domain as observed in plant CLEs. Taken together, our studies provide additional evidence to indicate the importance of ligand mimicry in cyst nematode parasitism.