Hormone-mediated disassembly and inactivation of a plant E3 ubiquitin ligase complex
Cristina Martínez,
Elisa Iniesto,
Marta García-León,
Daniel García-Corredera,
Sandra Fonseca,
César Santiago,
Mei Yang,
Renbo Yu,
Haodong Chen,
Eva Altmann,
Martin Renatus,
Xing Wang Deng,
Vicente Rubio
Affiliations
Cristina Martínez
Departments of Plant Molecular Genetics, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Darwin 3, Campus de Cantoblanco, 28049 Madrid, Spain
Elisa Iniesto
Departments of Plant Molecular Genetics, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Darwin 3, Campus de Cantoblanco, 28049 Madrid, Spain
Marta García-León
Departments of Plant Molecular Genetics, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Darwin 3, Campus de Cantoblanco, 28049 Madrid, Spain
Daniel García-Corredera
Departments of Plant Molecular Genetics, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Darwin 3, Campus de Cantoblanco, 28049 Madrid, Spain
Sandra Fonseca
Departments of Plant Molecular Genetics, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Darwin 3, Campus de Cantoblanco, 28049 Madrid, Spain
César Santiago
Macromolecular Structures, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Darwin 3, Campus de Cantoblanco, 28049 Madrid, Spain
Mei Yang
Peking University Institute of Advanced Agricultural Sciences, Weifang, Shandong 261325, China
Renbo Yu
National Key Laboratory of Tropical Crop Biobreeding, Hainan University, Sanya/Haikou, Hainan 572024/571101, China
Haodong Chen
Center for Plant Biology, School of Life Sciences, Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China
Eva Altmann
Global Discovery Chemistry, WSJ-386 1 14.32, 4056 Basel, Switzerland
Martin Renatus
Novartis Institutes for BioMedical Research, Forum 1, Novartis Campus, 4002 Basel, Switzerland
Xing Wang Deng
Peking University Institute of Advanced Agricultural Sciences, Weifang, Shandong 261325, China; State Key Laboratory of Wheat Improvement, Peking-Tsinghua Center for Life Sciences, School of Advanced Agriculture Sciences and School of Life Sciences, Peking University, Beijing 100871, China
Vicente Rubio
Departments of Plant Molecular Genetics, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Darwin 3, Campus de Cantoblanco, 28049 Madrid, Spain; Corresponding author
Summary: Phytohormone abscisic acid (ABA) regulates key plant development and environmental stress responses. The ubiquitin-proteasome system tightly controls ABA signaling. CULLIN4-RING (CRL4) E3 ubiquitin ligases use the substrate receptor module CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP10)-DDB1-DET1-DDA1 (CDDD) to target Arabidopsis ABA receptor PYL8, acting as negative regulators of ABA responses. Conversely, ABA treatment attenuates PYL8 receptor degradation, although the molecular mechanism remained elusive. Here, we show that ABA promotes the disruption of CRL4-CDDD complexes, leading to PYL8 stabilization. ABA-mediated CRL4-CDDD dissociation likely involves an altered association between DDA1-containing complexes and the COP9 signalosome (CSN), a master regulator of the assembly of cullin-based E3 ligases, including CRL4-CDDD. Indeed, treatment with CSN inhibitor CSN5i-3 suppresses the ABA effect on CRL4-CDDD assembly. Our findings indicate that ABA stabilizes PYL8 by altering the dynamics of the CRL4-CDDD-CSN complex association, showing a regulatory mechanism by which a plant hormone inhibits an E3 ubiquitin ligase to protect its own receptors from degradation.
