Cydne Ratliff is a rising junior at Drake University, majoring in Biology. Cydne is working in Dr. Lucia Strader’s lab, using confocal fluorescent microscopy to study peroxisomes in Arabidopsis to determine how cells moderate peroxisome growth and numbers.
The plant hormone auxin regulates plant growth and development via auxin response factors (ARFs). In Arabadopsis, these DNA-binding proteins can form biomolecular condensates, protein aggregates with unknown functions. Condensate-forming proteins often contain intrinsically disordered regions (IDRs) that are thought to contribute to protein aggregation. However, the direct role of IDRs in condensate formation and maturation is currently unknown. Here we show, switching the IDR regions of varying ARFs can induce changes in condensate morphology. Drastic differences in size, shape, and condensate number were observed when ARFs with swapped IDRs were expressed. By interchanging IDRs in ARF proteins, we have identified that IDRs contribute to the morphology of condensates. We anticipate that these results will aid in the identification of crucial regions within ARF proteins as they relate to condensate formation. Since the structure and physiology of ARF condensates are widely unknown, a better understanding of their IDRs may aid in future studies regarding these condensate-forming transcription factors and their roles in auxin pathways.