Research

  • In a second project, we are generating a large collection of transposon-induced, sequence-indexed, single gene knockout lines in maize using the maize Ac/Ds transposable element system. These gene knockouts are publicly available to all researchers. Through this work we are investigating determinants of transposon insertion site specificity. Based on computational approaches including analyses of DNA structural features and a machine learning approach, we are characterizing the structural code recognized by the transposase enzyme. This work has long term relevance to transposon biology and forward and reverse genetics approaches in maize, and in general to transgenic gene targeting technologies in eukaryotic organisms.

  • Finally, we are also working to elucidate developmental and genetic mechanisms that operate during the gametophyte generations of maize. Current approaches to these questions include mutagenesis using maize tertiary trisomic lines and transposon genetics, and RNAseq transcriptome profiling of the gametophytes.

    Funding: NSF Plant Genome Research Program – Award #0701731
    Functional Genomics of Maize Gametophytes www.maizegametophyte.org

  • Much of our work focuses on floral shoot branching in maize as an experimental system. The tassel and ear of maize comprise an attractive system because a series of shoot apical meristem fate decisions underlies normal development, and because their accessibility and large size facilitates their use in developmental and molecular experiments that exploit a plethora of research tools available in maize. In addition, the tassel and ear produce grain that is an important food and industrial commodity, and they are excellent models for other cereals. We identify genes important for floral branching in maize, use molecular techniques to understand the function of those gene products, and examine gene function in a broad, comparative context to evaluate its relevance to changes in crops during evolution, domestication and breeding.