Minisymposium 17: Evolution of Plant Development

Abs # 31003: The Floral Genome Project – Comparative analysis of sequence and expression of florally expressed genes

Presenter:	dePamphilis, C. , cwd3@psu.edu
Authors	dePamphilis, C.  (A)   Ma, H.  (A)   Soltis, D.  (B)   Soltis, P.  (B)   Carlson, J.  (A)   Tanksley, S.  (C)   Leebens-Mack, J.  (A)   Farmerie, W.  (B)   Frohlich, M  (E)   Field, D.  (F)   Zahn, L.  (A)   Kim, S.  (B)   Buzgo, M.  (B)   Kong, H.  (A)   Arrington, J.  (A)   Landherr, L  (A)   Hu, Yi  (A)   Wall, K  (A)   Ilut, D.  (C)   Albert, V.  (G)   Doyle, J.  (C)   Farris, J.S.  (I)   Oppenheimer, D.  (D)   Theissen, G.  (H)
Affiliations:	(A): Penn State University (B): University of Florida (C): Cornell University (D): University of Alabama (E): British Museum of Natural History (F): C.E.H. Oxford (G): University of Oslo (H): University of Jena (I): Naturhistoriska riksmuseet
Web Site:	http://www.floralgenome.org

Much of the knowledge about genes controlling flower development is derived from studies of a few model plants such as Arabidopsis, Antirrhinum, petunia, maize, and rice, which are members of the eudicot and monocot groups. At the same time, a great deal of floral morphological diversity is found among the basal angiosperm and basal eudicot lineages. How the floral developmental program originated and diversified, and how much of what we already know from models is generally applicable to floral development in other species, remain central questions. The Floral Genome Project (FGP) aims to identify florally expressed genes from 13 angiosperm species that occupy important phylogenetic positions, and reproductive genes of two gymnosperm species. Thousands of ESTs will be generated per species from early (premeiotic) floral (or reproductive) libraries, and a subset of complete cDNA sequences will be determined from selected species. Phylogenetic analysis will be performed with many gene families to identify homologs of known floral regulatory genes and to uncover new floral genes and gene families. Microarray and in situ hybridization will be used to determine their expression patterns. The FGP sequences and expression data will be compared with data from other species to derive a consensus set of floral regulators. At the same time, genes that might be specific to a lineage or responsible for distinctive structural properties can be identified and characterized. Based on the first 25,000 EST sequences sampled from six species, the project has identified homologs of a wide range of known floral regulators in the most basal lineages of angiosperms as well as gymnosperms and basal eudicots. Thousands of additional genes have been detected; most of these are the first representatives of their respective gene family in any basal angiosperm. New statistical analyses have been used to consistently define all gene families from Arabidopsis, rice, and other species, and serve as a basis for comparative analysis of plant genes. These results suggest a striking similarity of floral transcriptomes at the gene family level, leading to the conclusion that the ancestral angiosperm probably had a diverse “tool kit” of floral regulators and other florally expressed genes. Progress during the first 1.5 years will be presented and their implications for the conservation and divergence of floral regulators will be discussed.