Poster: Reproductive development

Abs # 365: Characterization and functional analysis of CCE1, a Brassica oleracea gene expressed in a variety-specific manner

Presenter:	Cruz-Alvarez, Marilyn , malvarez@fgcu.edu
Authors	Cruz-Alvarez, Marilyn  (A)   Seoanes, Rose  (A)   Baumgart, Ronald  (A)   Caulfield, Thomas  (A)   Singer, Jamie  (A)   Tellez, Luisa  (A)   Denda, Miwako  (B)   Fujinuma, Toshinori  (B)
Affiliations:	(A): Florida Gulf Coast University (B): Salem-Teikyo University

The Brassica oleracea gene CCE1, cauliflower curd expression 1 , is expressed in a variety-specific manner consistent with a role in the proliferation and/or developmental arrest that take place in the meristems of the cauliflower (var. botrytis) curd. Results from Southern blot analyses have indicated that there are a few gene copies containing CCE1 sequences in the B. oleracea genome of all varieties analyzed, and that CCE1 sequences are conserved among members of the Brassiceae tribe (B. oleracea, B. nigra, B. rapa and Raphanus sativus). However, no ortholog has been detected in Arabidopsis thaliana, another member of the Cruciferae family. Due to the lack of sequence homology of CCE1 to any other characterized genes, little information is available regarding the function of the putative protein encoded by this gene. Analyses of the deduced amino acid sequence have indicated that CCE1 would include transmembrane regions, and motifs conserved in G-protein coupled receptors, and have led to the notion that CCE1 may function as a cell membrane receptor. To determine the subcellular localization of the CCE1 protein we are currently: (1) analyzing the expression of a CCE1-GFP fusion protein in transgenic Arabidopsis plants, and (2) purifying a His-tagged CCE1 protein produced in insect cells for generation of specific antibodies. Functional studies are being carried out in vivo by analyzing the effect of overexpression of CCE1 in broccoli, and the effect of suppression of expression of CCE1 in cauliflower. Results from the characterization of cauliflower CCE1 genomic clones, subcellular localization studies, and in vivo functional studies of CCE1 will be presented.