Download MendeleyStructural basis for zinc-induced activation of a zinc uptake transcriptional regulator.
Liu, F., Su, Z., Chen, P., Tian, X., Wu, L., Tang, D.J., Li, P., Deng, H., Ding, P., Fu, Q., Tang, J.L., Ming, Z.(2021) Nucleic Acids Res 49: 6511-6528
- PubMed: 34048589
- DOI: https://doi.org/10.1093/nar/gkab432
- Primary Citation of Related Structures:
7DH7, 7DH8 - PubMed Abstract:
The zinc uptake regulator (Zur) is a member of the Fur (ferric uptake regulator) family transcriptional regulators that plays important roles in zinc homeostasis and virulence of bacteria. Upon zinc perception, Zur binds to the promoters of zinc responsive genes and controls their transcription. However, the mechanism underlying zinc-mediated Zur activation remains unclear. Here we report a 2.2-Å crystal structure of apo Zur from the phytopathogen Xanthomonas campestris pv. campestris (XcZur), which reveals the molecular mechanism that XcZur exists in a closed inactive state before regulatory zinc binding. Subsequently, we present a 1.9-Å crystal structure of holo XcZur, which, by contrast, adopts an open state that has enough capacity to bind DNA. Structural comparison and hydrogen deuterium exchange mass spectrometry (HDX-MS) analyses uncover that binding of a zinc atom in the regulatory site, formed by the hinge region, the dimerization domain and the DNA binding domain, drives a closed-to-open conformational change that is essential for XcZur activation. Moreover, key residues responsible for DNA recognition are identified by site-directed mutagenesis. This work provides important insights into zinc-induced XcZur activation and valuable discussions on the mechanism of DNA recognition.
Organizational Affiliation:
State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi Key Laboratory for Sugarcane Biology, Guangxi University, Nanning 530004, China.
