Poster: Secondary Metabolism

Abs # 306: The role of a novel set of cis-prenyltransferases in plants

Presenter:	Alonzo, Virginia A., gigi@pop.ucr.edu
Authors	Alonzo, Virginia A. (A)   Walling, Linda L (A)
Affiliations:	(A): University of California, Riverside

Isoprenoids are a diverse group of compounds that are involved in plant growth, development, defense signalling, and cell wall biosynthsis. The starting material for isoprenoid biosynthesis is the five-carbon isoprene, isopentyl diphosphate (IPP). Its condensation with other isoprenyl units (farnesyl diphosphate and geranyldiphosphate) is catalyzed by prenyltransferases. Previous studies in citrus led us to the identification of a seed-specific gene that is highly related to a novel set of cis-prenyltransferases (CPTs) in plants. These transferases are distinct from plastidial trans-prenyltransferases and to other cytosolic cis-prenyltransferases such as dedolichyldiphosphate synthase. In the model plant Arabidopsis thaliana, there are 3 genes (CPT1, CPT2, CPT3) that encode proteins that are believed to be part of this novel set of CPTs. In this study, we are using T-DNA insertion lines in A. thaliana to study these genes. The cDNAs of these genes, under the regulatory control of the pUNI shuttling vectors, will be used to generate HIS- and GST-tagged fusion constructs for overexpression of the proteins. The enzymatic activity of these overexpressed proteins will be determined. Characterization of T-DNA knockout lines and patterns of RNA accumulation will be presented.