Poster: Vegetative Development

Abs # 453: Characterization of a Highly Conserved Protein Predicted to be Involved in Plant Development or Defense

Presenter:	Long, Terri A, tlong@arches.uga.edu
Authors	Long, Terri A (A)   Covert, Sarah F (B)
Affiliations:	(A): University of Georgia, Department of Genetics (B): University of Georgia, School of Forest Resources

Infection of loblolly pine by the biotrophic pathogen, Cronartium quercuum f. sp. fusiforme, causes spindle-shaped galls to form due to swelling, distortion and accumulation of the cells that make up woody tissue. Our lab has identified several pine cDNAs that are suppressed in galled tissue. One of these, PT55, is highly homologous to a single gene of unknown function in Arabidopsis thaliana. It also is similar to ESTs collected from a wide variety of plant species. The objective of this project is to determine the function of the PT55 ortholog in A. thaliana (AT55), and thus infer how its suppression contributes to disease development and (or) gall formation. Based on previous research we hypothesize that it is involved in regulating cell proliferation, shape, or differentiation. Alternatively, this protein may be involved in pathogen recognition or response. Transgenic A. thaliana plants containing AT55 promoter-GUS fusions show GUS expression in young leaves and stems, stamens, and wounded tissues. Constitutive overexpression of AT55 in A. thaliana produces dimpled and discolored leaves. Constitutive heterologous expression of PT55 also causes A. thaliana leaves to develop in the same, abnormal fashion. Ongoing work includes characterization of RNAi mediated suppression of AT55 in A. thaliana, and determining whether AT55 is involved in hormone and (or) pathogen recognition and response.