Raul Correa

Ph.D. Candidate in Genetics

Department of Botany

430 Lincoln Drive

University of Wisconsin

Madison, WI 53706-1381

Office: 220 Birge Hall
Phone: (608) 265-7929

Fax: (608) 262-7509
Email: rcorrea@wisc.edu

Educational Background:

BA in Biology, Pomona College, 2003

Research Interests:

The genetic basis of the morphological evolution of species

Hobbies:

Traveling, reading, sports, outdoor activities

Current Project:

Can a transgenomic screen identify genes that cause morphological evolution?

Which genes cause the morphological evolution of species? A central tenet of evolutionary biology is that phenotypic differences between species arise through evolutionary changes in genes. Yet to date, a relatively small number of these genes have been identified. One way to identify these genes is to determine which genes currently account for species differences (genes known as species-difference genes or SDGs). For my dissertation research, I have developed a new forward genetic screen in plants, named "transgenomics", to identify SDGs. A transgenomic screen begins by taking two closely related plant species that differ in many phenotypes. Many genomic inserts of one plant species, known as the donor species, are then moved into the wildtype background of the second, or recipient species, using high-throughput transformation methods. This generates many primary transformant (or T1) plants that are then visibly screened for morphological effects that deviate from the recipient's phenotype, with a special interest in any effect that resembles the donor species. Any donor insert that causes the transfer of a donor phenotype into the recipient species would be of very high interest since it is likely to contain an SDG that importantly contributed to the evolution of that one morphological difference.

I implemented transgenomics by screening 1,134 large inserts of the gladecress plant Leavenworthia alabamica for morphological effects in the Arabidopsis thaliana Columbia background. Following rigorous downstream analyses that eliminated several inserts that were initially interesting, I found evidence of two L. alabamica inserts causing a visible morphological effect in the A. thaliana Columbia background (one insert causes shorter fruit while the other causes longer seed). Future optimizations of transgenomics should enhance its ability to identify additional inserts of interest and potentially SDGs.

Publications:

Correa, R., Dilkes, B., and Baum, D. A. In preparation. A transgenomic screen for genes causing morphological evolution.

Liu, N., Sliwinski M.K., Correa, R., and Baum, D. A. In preparation. TFL1-LFY interactions and the evolution of rosette flowering in Leavenworthia (Brassicaceae).