RT Journal Article
SR Electronic
T1 Selective auxin agonists induce specific AUX/IAA protein degradation to modulate plant development
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 381608
DO 10.1101/381608
A1 Thomas Vain
A1 Sara Raggi
A1 Noel Ferro
A1 Deepak Kumar Barange
A1 Martin Kieffer
A1 Qian Ma
A1 Siamsa M. Doyle
A1 Mattias Thelander
A1 Barbora Pařízková
A1 Ondřej Novák
A1 Alexandre Ismail
A1 Per Anders Enquist
A1 Adeline Rigal
A1 Małgorzata Łangowska
A1 Sigurd Ramans Harborough
A1 Yi Zhang
A1 Karin Ljung
A1 Judy Callis
A1 Fredrik Almqvist
A1 Stefan Kepinski
A1 Mark Estelle
A1 Laurens Pauwels
A1 Stéphanie Robert
YR 2018
UL http://biorxiv.org/content/early/2018/07/31/381608.abstract
AB Auxin phytohormones control most aspects of plant development through a complex and interconnected signaling network. In the presence of auxin, AUXIN/INDOLE-3-ACETIC ACID (AUX/IAA) transcriptional repressors are targeted for degradation by the SKP1-CULLIN1-F-BOX (SCF) ubiquitin-protein ligases containing TRANSPORT INHIBITOR RESISTANT 1/AUXIN SIGNALING F-BOX (TIR1/AFB). CULLIN1-neddylation is required for SCFTIR1/AFB functionality as exemplified by mutants deficient in the NEDD8-activating enzyme subunit AUXIN-RESISTANT 1 (AXR1). Here, we report a chemical biology screen that identifies small molecules requiring AXR1 to modulate plant development. We selected four molecules of interest, RubNeddin1 to 4 (RN1 to 4), among which RN3 and RN4 trigger selective auxin responses at transcriptional, biochemical and morphological levels. This selective activity is explained by their ability to promote the interaction between TIR1 and a specific subset of AUX/IAA proteins, stimulating the degradation of particular AUX/IAA combinations. Finally, via a genetic screen using RN4, we revealed that the chromatin remodeling ATPase BRAHMA is implicated in auxin-mediated apical hook development. These results demonstrate the power of selective auxin agonists to dissect auxin perception for plant developmental functions.