Genomics of Chamaecrista fasciculata, a native praire plant with potential for mixed prairie biomass

With Jeff Doyle (Cornell), Greg May (NCGR), and Steven Cannon (Iowa State), we are developing Chamaecrista fasciculata as a model organism to test key questions about the evolution of the Leguminosae (a large family of plants bearing bean pods), several members of which are important agricultural crops or key model organisms for genetic analysis. These questions include 1) whether polyploidy is an ancient feature of this family, or characteristic of the more recently-evolved species only, 2) whether nodules containing symbiotic bacteria in C. fasciculata evolved independently from those common in other legumes, and 3) which genes for flowering time and flower structure are unique to the legumes, conserved within the legumes, and divergent in the more recent legumes. To address these questions, the researchers will sequence all of the active genes in C. fasciculata roots and shoots. These sequences and their resulting interpretation will contribute significantly to research on legumes and to our general understanding of the evolution of this important group. Comparative genetic analysis of Chamaecrista will also shed light on the divergence of the legumes from the last common ancestor shared with Arabidopsis, which is the current model for most genetic analyses.

Although advances in biotechnology now make detailed genetic data available to undergraduates at small schools, the potential opportunities to integrate genomics research and education at smaller schools have yet to be fully realized. This project brings new-generation sequencing technology and the opportunity to work with whole sequences of expressed or active genes to an undergraduate school, to broaden participation within the academy and in the workforce. An educational module based on the proposed research will be developed at Carleton College, informed by interactions with Cornell and the National Center for Genome Resources (NCGR). The module will be accessible to high school teachers through the Cornell Institute for Biology Teachers and to teachers and students at Hispanic-Serving Institutions (HSI), community colleges and Tribal Colleges and Universities (TCUP), through educational programs at NCGR.

Genetic Regulation of Inflorescence Architecture in Pea

The evolution of inflorescence architecture involves a common toolkit of flowering genes used in different ways to create diverse morphologies, which can dramatically affect reproductive success. Using a candidate gene approach, we are identifying genes that correspond to known inflorescence phenotypes in pea. We are interested in the interactions among these genes in terms of phenotype and gene expression. We are particularly interested in COCH, PIM, DET, UNI, and VEG1 interact to regulate determinancy in inflorescences. Below are images of wild type, coch, pim, and coch pim plants and a few sketches of their branching patterns of the axillary inflorescence.

Modeling Genetic Regulation of Inflorescence Development

Creating and comparing systems-based models of shoot development in different species may reveal subtle variations that result in distinct patterns. To test hypotheses about gene interaction and aid in the design of future experiments, we are using L-systems to create process-based models of inflorescence development. This work is in collaboration with our colleagues Jim Hanan and Christine Beveridge at the University of Queensland. We do our modeling work using L-Studio.