|Ha, Chan Man|
Submitted to: Plant Physiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/12/2010
Publication Date: 12/1/2010
Publication URL: http://www.plantphysiol.org/content/154/4/1721.full
Citation: Jun, J., Fiume, E., Roeder, A.H., Meng, L., Sharma, V.K., Osmont, K.S., Baker, C., Ha, C., Meyerowitz, E.M., Feldman, L.J., Fletcher, J.C. 2010. Comprehensive analysis of CLE polypeptide signaling gene expression and overexpression activity in Arabidopsis. Plant Physiology. 154:1721-1736. Interpretive Summary: Interpretive Summary: The Arabidopsis CLE genes encode members of a large family of plant-specific proteins that are exported from the cells in which they are made and send signals to neighboring cells to affect their behavior. Because little is known about the functions of these proteins in coordinating important cellular processes, we performed a systematic analysis of their expression during Arabidopsis seedling and flower development. We determined that all Arabidopsis tissues make at least one CLE gene, and that most tissues make multiple CLE genes in overlapping patterns. We also found that eliminating the activity of single CLE genes had no deleterious effects on the plant. Our research shows that CLE genes are likely to function in many different processes during the growth of Arabidopsis tissues and cells, and reveals the existence of multiple signaling pathways as potential targets for manipulation to benefit agriculture.
Technical Abstract: Technical Abstract: Intercellular signaling is essential for the coordination of growth and development in higher plants. Although hundreds of putative receptors have been identified in Arabidopsis (Arabidopsis thaliana), only a few families of extracellular signaling molecules have been discovered, and their biological roles are largely unknown. To expand our insight into the developmental processes potentially regulated by ligand-mediated signal transduction pathways, we undertook a systematic expression analysis of the members of the Arabidopsis CLAVATA3/ESR-RELATED (CLE) small signaling polypeptide family. Using reporter constructs, we show that the CLE genes have distinct and specific patterns of promoter activity. We find that each Arabidopsis tissue expresses at least one CLE gene, indicating that CLE-mediated signaling pathways are likely to play roles in many biological processes during the plant life cycle. Some CLE genes that are closely related in sequence have dissimilar expression profiles, yet in many tissues multiple CLE genes have overlapping patterns of promoter-driven reporter activity. This observation, plus the general absence of detectable morphological phenotypes in cle null mutants, suggest that a high degree of functional redundancy exists among CLE gene family members. Our work establishes a community resource of CLE- related biological materials and provides a platform for understanding and ultimately manipulating many different plant signaling systems.