Grant: Discovery Grants Program - Individual

A remarkable degree of architectural diversity exists between plant species. An important goal of plant developmental biologists has been to identify genes that control patterning and to understand how these genes sculpt plant organs. My laboratory studies how genes control shape and form with an emphasis on understanding the molecular mechanisms that control leaf and floral patterning in the model plant species Arabidopsis thaliana. Little is currently known about how spatial cues regulate growth asymmetry, a crucial aspect of patterning.  I have recently identified a role for two NONEXPRESSOR OF PATHOGENESIS-RELATED PROTEINS1 (NPR1)-like signaling proteins, BLADE-ON-PETIOLE (BOP) 1 and 2 in this process.  NPR1 and its role in plant defense is well-studied.  Pathogen attack leads to the accumulation of a signal molecule salicylic acid (SA) followed by altered intracellular redox potential.  NPR1 responds to changes in redox-state by becoming monomeric in form, entering the nucleus, and interacting with TGA (TGACG sequence-specific binding) transcription factors which then bind to SA-response elements in the promoters of defense genes.  The BOP proteins are structurally related to NPR1 and our preliminary analyses suggest that they function in a signaling cascade that is mechanistically similar to that of NPR1.  We intend to further examine the mechanism of BOP signaling, to identify proteins that interact with BOP1/2, to identify modifiers and downstream targets of BOP activity, and to determine how BOP interacts with other genes that regulate leaf and floral patterning.  This work will provide fresh insight into how bilateral patterning of leaves and flowers is governed and give valuable molecular details about a possible redox-control mechanism that functions in plant development.  Ultimately, our work will generate valuable tools for the manipulation of leaf and floral form and provide insights into the molecular basis of plant architectural diversity.