Destabilization of strigolactone receptor DWARF14 by binding of ligand and E3-ligase signaling effector DWARF3
journal contribution
posted on 2023-05-18, 15:28authored byZhao, L-H, Zhou, XE, Yi, W, Wu, Z, Liu, Y, Kang, Y, Hou, L, de Waal, PW, Li, S, Jiang, Y, Scaffidi, A, Flemmati, GR, Steven SmithSteven Smith, Lam, VQ, Griffin, PR, Wang, Y, Li, J, Melcher, K, Xu, HE
Strigolactones (SLs) are endogenous hormones and exuded signaling molecules in plant responses to low levels of mineral nutrients. Key mediators of the SL signaling pathway in rice include the α/β-fold hydrolase DWARF 14 (D14) and the F-box component DWARF 3 (D3) of the ubiquitin ligase SCFD3 that mediate ligand-dependent degradation of downstream signaling repressors. One perplexing feature is that D14 not only functions as the SL receptor but is also an active enzyme that slowly hydrolyzes diverse natural and synthetic SLs including GR24, preventing the crystallization of a binary complex of D14 with an intact SL as well as the ternary D14/SL/D3 complex. Here we overcome these barriers to derive a structural model of D14 bound to intact GR24 and identify the interface that is required for GR24-mediated D14-D3 interaction. The mode of GR24-mediated signaling, including ligand recognition, hydrolysis by D14, and ligand-mediated D14-D3 interaction, is conserved in structurally diverse SLs. More importantly, D14 is destabilized upon the binding of ligands and D3, thus revealing an unusual mechanism of SL recognition and signaling, in which the hormone, the receptor, and the downstream effectors are systematically destabilized during the signal transduction process.
Funding
Australian Research Council
History
Publication title
Cell Research
Volume
25
Issue
11
Pagination
1219-1236
ISSN
1001-0602
Department/School
School of Natural Sciences
Publisher
Science China Press
Place of publication
16 Donghuangchenggen North St, Beijing, Peoples R China, 100717