PUX10 Is a CDC48A Adaptor Protein That Regulates the Extraction of Ubiquitinated Oleosins from Seed Lipid Droplets in Arabidopsis
| Autor: | Isabelle Bouchez, Carine Deruyffelaere, Zita Purkrtova, Boris Collet, Sabine d'Andrea, Jean-Luc Cacas, Thierry Chardot, Jean-Luc Gallois |
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| Přispěvatelé: | Institut Jean-Pierre Bourgin (IJPB), Institut National de la Recherche Agronomique (INRA)-AgroParisTech, Génétique et Amélioration des Fruits et Légumes (GAFL), Institut National de la Recherche Agronomique (INRA), ANR-10- LABX-0040-SPS, Unité de recherche Génétique et amélioration des fruits et légumes (GALF) |
| Rok vydání: | 2018 |
| Předmět: |
0301 basic medicine
Protein family [SDV]Life Sciences [q-bio] Signal transducing adaptor protein Cell Biology Plant Science Biology biology.organism_classification AAA proteins Cell biology 03 medical and health sciences 030104 developmental biology Ubiquitin Lipid droplet Arabidopsis biology.protein Arabidopsis thaliana Oleosin |
| Zdroj: | The Plant cell The Plant cell, American Society of Plant Biologists (ASPB), 2018, 30 (9), pp.2116-2136. ⟨10.1105/tpc.18.00275⟩ Plant Cell Plant Cell, American Society of Plant Biologists, 2018, 30 (9), pp.2116-2136. ⟨10.1105/tpc.18.00275⟩ |
| ISSN: | 1532-298X 1040-4651 |
| Popis: | International audience; Post-germinative mobilization of neutral lipids stored in seed lipid droplets (LDs) is preceded by the degradation of oleosins, the major structural LD proteins that stabilize LDs in dry seeds. We previously showed that Arabidopsis thaliana oleosins are marked for degradation by ubiquitination, and extracted from LDs before proteolysis. However, the mechanisms underlying the dislocation of these LD-anchored proteins from the LD monolayer are yet unknown. Here, we report that PUX10, a member of the plant UBX-domain containing (PUX) protein family, is an integral LD protein that associates with a subpopulation of LDs during seed germination. In pux10 mutant seedlings, PUX10 deficiency impaired the degradation of ubiquitinated oleosins, and prevented the extraction of ubiquitinated oleosins from LDs. We also showed that PUX10 interacts with ubiquitin and CDC48A, the AAA ATPase Cell Division Cycle 48, through its UBA and UBX domains, respectively. Collectively, these results strongly suggest that PUX10 is an adaptor recruiting CDC48A to ubiquitinated oleosins, thus facilitating the dislocation of oleosins from LDs by the segregase activity of CDC48A. We propose that PUX10 and CDC48A are core components of a LD-associated degradation machinery, which we named the LD-associated degradation (LDAD) system. Importantly, PUX10 is also the first determinant of a LD subpopulation described in plants, suggesting functional differentiation of LDs in Arabidopsis seedlings. |
| Databáze: | OpenAIRE |
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