Download MendeleyStructural basis for the regulation of plant transcription factor WRKY33 by the VQ protein SIB1.
Dong, X., Yu, L., Zhang, Q., Yang, J., Gong, Z., Niu, X., Li, H., Zhang, X., Liu, M., Jin, C., Hu, Y.(2024) Commun Biol 7: 561-561
- PubMed: 38734744
- DOI: https://doi.org/10.1038/s42003-024-06258-7
- Primary Citation of Related Structures:
8K31 - PubMed Abstract:
The WRKY transcription factors play essential roles in a variety of plant signaling pathways associated with biotic and abiotic stress response. The transcriptional activity of many WRKY members are regulated by a class of intrinsically disordered VQ proteins. While it is known that VQ proteins interact with the WRKY DNA-binding domains (DBDs), also termed as the WRKY domains, structural information regarding VQ-WRKY interaction is lacking and the regulation mechanism remains unknown. Herein we report a solution NMR study of the interaction between Arabidopsis WRKY33 and its regulatory VQ protein partner SIB1. We uncover a SIB1 minimal sequence neccessary for forming a stable complex with WRKY33 DBD, which comprises not only the consensus "FxxhVQxhTG" VQ motif but also its preceding region. We demonstrate that the β N -strand and the extended β N -β 1 loop of WRKY33 DBD form the SIB1 docking site, and build a structural model of the complex based on the NMR paramagnetic relaxation enhancement and mutagenesis data. Based on this model, we further identify a cluster of positively-charged residues in the N-terminal region of SIB1 to be essential for the formation of a SIB1-WRKY33-DNA ternary complex. These results provide a framework for the mechanism of SIB1-enhanced WRKY33 transcriptional activity.
Organizational Affiliation:
State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, China.
