Strigolactone perception and deactivation by a hydrolase receptor DWARF14

Abstract

The perception mechanism for the strigolactone (SL) class of plant hormones has been a subject of debate because their receptor, DWARF14 (D14), is an α/β-hydrolase that can cleave SLs. Here we show via time-course analyses of SL binding and hydrolysis by Arabidopsis thaliana D14, that the level of uncleaved SL strongly correlates with the induction of the active signaling state. In addition, we show that an AtD14D218A catalytic mutant that lacks enzymatic activity is still able to complement the atd14 mutant phenotype in an SL-dependent manner. We conclude that the intact SL molecules trigger the D14 active signaling state, and we also describe that D14 deactivates bioactive SLs by the hydrolytic degradation after signal transmission. Together, these results reveal that D14 is a dual-functional receptor, responsible for both the perception and deactivation of bioactive SLs.

Differential role of MAX2 and strigolactones in pathogen, ozone, and stomatal responses

“…MAX2 is an F‐box protein that targets proteins for destruction as part of the ubiquitin–proteasome system (Lechner, Achard, Vansiri, Potuschak, & Genschik, ; Stirnberg, Sande, & Leyser, ). D14 represents a novel system for hormone perception, as this protein both acts as a receptor for strigolactone and degrades strigolactone (Seto et al, ). Binding of strigolactone to D14 facilitates the interaction of D14 with SCF MAX2 (SKP1‐CUL1‐F‐box), an E3 ligase functioning in ubiquitination (Lv et al, ).…”

“…Targets for MAX2‐directed protein degradation include SUPPRESSOR OF MORE AXILLARY GROWTH2‐LIKE6 (SMXL6), SMXL7, and SMXL8 (Wang et al, ). As D14 also degrades strigolactone, this represents a direct way for terminating the strigolactone signal (Seto et al, ).…”

“…As D14 also degrades strigolactone, this represents a direct way for terminating the strigolactone signal (Seto et al, 2019).…”

Regulation of biosynthesis, perception, and functions of strigolactones for promoting arbuscular mycorrhizal symbiosis and managing root parasitic weeds

“…) was screened as a potent inhibitor of hydrolysis; it covalently binds to the hydroxyl group of the serine residue in the catalytic domain of D14 . However, Seto et al have shown that intact SL molecules induce an active signaling state in D14 and hydrolysis of SLs is a degradation step . KK094 appears to inhibit SL signaling by occupying the catalytic site of D14 through binding to the serine residue.…”

Strigolactone: Pflanzenhormone mit vielversprechenden Eigenschaften

“…Auch hier half der Verzweigungs-Phänotyp von Mutanten, um Komponenten der Strigolacton-Erkennung und Signalübertragung zu identifizieren. [43,45] Nach Bindung von Strigolacton/D-Ring verändert sich die Konformation von D14 auf eine Weise,dass dieses das F-Box-Protein MAX2/D3 rekrutiert (Abbildung 2). [15] Obwohl es als Rezeptor agiert, behielt D14 seine Hydrolase-Aktivität, und nach der Protein-Ligand-Interaktion wird der Strigolacton-Ligand hydrolysiert (Abbildung 2).…”