Dissection and Manipulation of LRR Domains in Plant Disease Resistance Gene Products.

[摘要] Leucine-rich repeat (LRR) protein domains offer a readily diversifiable platform - literally, an extended protein surface - for specific binding of very diverse ligands. The project addressed the following overlapping research questions: - How do leucine-rich repeat proteins recognize their cognate ligands? - What are the intra- and inter-molecular transitions that occur that cause transmembrane LRR proteins to switch between off and on states? - How do plants use LRR receptor proteins to activate disease resistance? - Can we synthetically evolve new LRR proteins that have acquired new ligand specificities? The following peer-reviewed primary research papers were published as part of the DOE-funded research: Sun*, W., Y. Cao*, K.L. Jansen, P. Bittel, T. Boller and A.F. Bent (*co-first authors), 2012. Probing the Arabidopsis flagellin receptor: FLS2-FLS2 association and the contributions of specific domains to signaling function. Plant Cell 24:1096-1113. DOI 10.1105/tpc.112.095919. Sun, W., L. Liu and A.F. Bent, 2011. Type III secretion dependent host defense elicitation and Type III secretion independent growth within leaves by Xanthomonas campestris pv.campestris. Mol. Plant Pathol. 12:731-745. DOI: 10.1111/J.1364-3703.2011.00707.X Helft, L., V. Reddy, X. Chen, T. Koller, L. Federici, J. Fernandez-Recio, R. Gupta and A. Bent, 2011. LRR Conservation Mapping to predict functional sites within protein leucine-rich repeat domains. PLoS ONE 6(7): e21614. doi:10.1371/journal.pone.0021614 Danna, C.H., Y.A. Millet, T. Koller, S.-W. Han, A.F. Bent, P.C. Ronald and F.M. Ausubel, 2011. The Arabidopsis flagellin receptor FLS2 mediates the perception of Xanthomonas Ax21 secreted peptides. Proc. Natl. Acad. Sci. (USA) 108:9286-9291. Two additional manuscripts are currently complete, one is submitted and is now being revised according to referee suggestions, and the other is not yet submitted. The provisional titles of those papers are: FLS2/BIK1/BAK1 Association and Dissociation are Not Sufficient to Activate Arabidopsis Immunity but FLS2 Phosphorylation Site Ser-938 is Required. and Directed Evolution of FLS2 towards Novel Flagellin Peptide Recognition. An additional tangible outcome of the work is the public availability of a bioinformatics website that we developed, www.plantpath.wisc.edu/RCM, where researchers can enter primary amino acid sequences for two or more related leucine-rich repeat proteins and use the program to identify sites on the predicted surface of the LRR that have been most conserved or most diversified across the proteins. These sites are typically the key functional sites on the protein, such as ligand binding sites. Despite a shift of DOE priorities away from support of research on plant immune system function, we are continuing our work on the engineering or in vitro evolution of LRR proteins toward novel ligand specificities.

[发布日期] 2012-11-28

[学科分类] 生物科学（综合）

[关键词] Leucine-rich repeat;Transmembrane receptor