Physiological & Molecular Plant Biology (PMPB) Seminar – IB 513/CPSC 598
Wednesday, January 30, 2019, 12:00 – 12:50 PM // W-109 Turner Hall
Dr. Lucia Strader
Department of Biology, Washington University in St. Louis
Nucleo-cytoplasmic partitioning of ARF transcription factors driven by protein phase transitions
The phytohormone auxin plays crucial roles in nearly every aspect of plant growth and development. The AUXIN RESPONSE FACTOR (ARF) family of transcription factors regulates auxin-responsive gene expression and exhibit nuclear localization in regions of high auxin responsiveness. Here we show that the ARF7 and ARF19 proteins accumulate in micron-sized assemblies within the cytoplasm of tissues with attenuated auxin responsiveness. We found that the intrinsically disordered middle region and the folded PB1 interaction domain of ARFs drive protein assembly formation. Mutation of a single lysine within the PB1 domain abrogates cytoplasmic assemblies, promotes ARF nuclear loclization, and results in an altered transcriptome and morphological defects. Our data suggest a model in which ARF nucleo-cytoplasmic partitioning regulates auxin responsiveness, thus providing a mechanism for cellular competence for auxin signaling.
More information about Dr. Strader and her research can be found at: https://pages.wustl.edu/strader