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Chen Y, Vermeersch M, Van Leene J, De Jaeger G, Li Y, Vanhaeren H. A dynamic ubiquitination balance of cell proliferation and endoreduplication regulators determines plant organ size. SCIENCE ADVANCES 2024; 10:eadj2570. [PMID: 38478622 PMCID: PMC10936951 DOI: 10.1126/sciadv.adj2570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 02/08/2024] [Indexed: 03/17/2024]
Abstract
Ubiquitination plays a crucial role throughout plant growth and development. The E3 ligase DA2 has been reported to activate the peptidase DA1 by ubiquitination, hereby limiting cell proliferation. However, the molecular mechanisms that regulate DA2 remain elusive. Here, we demonstrate that DA2 has a very high turnover and auto-ubiquitinates with K48-linkage polyubiquitin chains, which is counteracted by two deubiquitinating enzymes, UBIQUITIN-SPECIFIC PROTEASE 12 (UBP12) and UBP13. Unexpectedly, we found that auto-ubiquitination of DA2 does not influence its stability but determines its E3 ligase activity. We also demonstrate that impairing the protease activity of DA1 abolishes the growth-reducing effect of DA2. Last, we show that synthetic, constitutively activated DA1-ubiquitin fusion proteins overrule this complex balance of ubiquitination and deubiquitination and strongly restrict growth and promote endoreduplication. Our findings highlight a nonproteolytic function of K48-linked polyubiquitination and reveal a mechanism by which DA2 auto-ubiquitination levels, in concert with UBP12 and UBP13, precisely monitor the activity of DA1 and fine-tune plant organ size.
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Affiliation(s)
- Ying Chen
- Ghent University, Department of Plant Biotechnology and Bioinformatics, Technologiepark 71, B-9052 Ghent, Belgium
- VIB Center for Plant Systems Biology, Technologiepark 71, B-9052 Ghent, Belgium
| | - Mattias Vermeersch
- Ghent University, Department of Plant Biotechnology and Bioinformatics, Technologiepark 71, B-9052 Ghent, Belgium
- VIB Center for Plant Systems Biology, Technologiepark 71, B-9052 Ghent, Belgium
| | - Jelle Van Leene
- Ghent University, Department of Plant Biotechnology and Bioinformatics, Technologiepark 71, B-9052 Ghent, Belgium
- VIB Center for Plant Systems Biology, Technologiepark 71, B-9052 Ghent, Belgium
| | - Geert De Jaeger
- Ghent University, Department of Plant Biotechnology and Bioinformatics, Technologiepark 71, B-9052 Ghent, Belgium
- VIB Center for Plant Systems Biology, Technologiepark 71, B-9052 Ghent, Belgium
| | - Yunhai Li
- State Key Laboratory of Plant Cell and Chromosome Engineering, CAS Centre for Excellence in Molecular Plant, Institute of Genetics and Development Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Hannes Vanhaeren
- Ghent University, Department of Plant Biotechnology and Bioinformatics, Technologiepark 71, B-9052 Ghent, Belgium
- VIB Center for Plant Systems Biology, Technologiepark 71, B-9052 Ghent, Belgium
- Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, Proeftuinstraat 86, 9000 Ghent, Belgium
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2
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Vogel K, Isono E. Deubiquitylating enzymes in Arabidopsis thaliana endocytic protein degradation. Biochem Soc Trans 2024; 52:291-299. [PMID: 38174770 DOI: 10.1042/bst20230561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 01/05/2024]
Abstract
The regulation of ubiquitylation is key for plant growth and development, in which the activities of ubiquitylating enzymes as well as deubiquitylating enzymes (DUBs) determine the stability or function of the modified proteins. In contrast with ubiquitylating enzymes, there are less numbers of DUBs. DUBs can be classified into seven protein families according to the amino acid sequence of their catalytic domains. The catalytic domains of animal and plant DUB families show high homology, whereas the regions outside of the catalytic site can vary a lot. By hydrolyzing the ubiquitin molecules from ubiquitylated proteins, DUBs control ubiquitin-dependent selective protein degradation pathways such as the proteasomal-, autophagic-, and endocytic degradation pathways. In the endocytic degradation pathway, DUBs can modulate the endocytic trafficking and thus the stability of plasma membrane proteins including receptors and transporters. To date, three DUB families were shown to control the endocytic degradation pathway namely associated molecule with the SH3 domain of STAM (AMSH) 3, ubiquitin-specific protease (UBP) 12 and UBP13, and ovarian tumor protease (OTU) 11 and OTU12. In this review we will summarize the activity, molecular functions, and target protein of these DUBs and how they contribute to the environmental response of plants.
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Affiliation(s)
- Karin Vogel
- Department of Biology, University of Konstanz, Universitätsstraße 10, D-78464 Konstanz, Germany
| | - Erika Isono
- Department of Biology, University of Konstanz, Universitätsstraße 10, D-78464 Konstanz, Germany
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3
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Zhang J, Wysocki R, Li F, Yu M, Martinoia E, Song WY. Role of ubiquitination in arsenic tolerance in plants. TRENDS IN PLANT SCIENCE 2023; 28:880-892. [PMID: 37002000 DOI: 10.1016/j.tplants.2023.03.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 02/18/2023] [Accepted: 03/09/2023] [Indexed: 06/19/2023]
Abstract
Arsenic (As) is harmful to all living organisms, including humans and plants. To limit As uptake and avoid its toxicity, plants employ systems that regulate the uptake of As from the soil and its translocation from roots to grains. Ubiquitination, a highly conserved post-translational modification (PTM) in all eukaryotes, plays crucial roles in modulating As detoxification mechanisms in budding yeast (Saccharomyces cerevisiae), but little is known about its roles in As tolerance and transport in plants. In this opinion article we review recent findings and suggest that ubiquitination plays a crucial role in regulating As transport in plants. We also propose ideas for future research to explore the importance of ubiquitination for enhancing As tolerance in crops.
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Affiliation(s)
- Jie Zhang
- Research Center for Environmental Membrane Biology and Department of Horticulture, Foshan University, Foshan, Guangdong 528000, China
| | - Robert Wysocki
- Faculty of Biological Sciences, University of Wroclaw, 50-328 Wroclaw, Poland
| | - Fangbai Li
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Min Yu
- Research Center for Environmental Membrane Biology and Department of Horticulture, Foshan University, Foshan, Guangdong 528000, China.
| | - Enrico Martinoia
- Research Center for Environmental Membrane Biology and Department of Horticulture, Foshan University, Foshan, Guangdong 528000, China; Institute of Plant Biology, University Zurich, Zollikerstrasse 107, 8008 Zurich, Switzerland.
| | - Won-Yong Song
- Research Center for Environmental Membrane Biology and Department of Horticulture, Foshan University, Foshan, Guangdong 528000, China; Department of Integrative Bioscience and Biotechnology, Pohang University of Science and Technology, Pohang 37673, Republic of Korea.
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4
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van Wijk KJ, Leppert T, Sun Z, Deutsch EW. Does the Ubiquitination Degradation Pathway Really Reach inside of the Chloroplast? A Re-Evaluation of Mass Spectrometry-Based Assignments of Ubiquitination. J Proteome Res 2023. [PMID: 37092802 DOI: 10.1021/acs.jproteome.3c00178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
A recent paper in Science Advances by Sun et al. claims that intra-chloroplast proteins in the model plant Arabidopsis can be polyubiquitinated and then extracted into the cytosol for subsequent degradation by the proteasome. Most of this conclusion hinges on several sets of mass spectrometry (MS) data. If the proposed results and conclusion are true, this would be a major change in the proteolysis/proteostasis field, breaking the long-standing dogma that there are no polyubiquitination mechanisms within chloroplast organelles (nor in mitochondria). Given its importance, we reanalyzed their raw MS data using both open and closed sequence database searches and encountered many issues not only with the results but also discrepancies between stated methods (e.g., use of alkylating agent iodoacetamide (IAA)) and observed mass modifications. Although there is likely enrichment of ubiquitination signatures in a subset of the data (probably from ubiquitination in the cytosol), we show that runaway alkylation with IAA caused extensive artifactual modifications of N termini and lysines to the point that a large fraction of the desired ubiquitination signatures is indistinguishable from artifactual acetamide signatures, and thus, no intra-chloroplast polyubiquitination conclusions can be drawn from these data. We provide recommendations on how to avoid such perils in future work.
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Affiliation(s)
- Klaas J van Wijk
- Section of Plant Biology, School of Integrative Plant Sciences (SIPS), Cornell University, Ithaca, New York 14853, United States
| | - Tami Leppert
- Institute for Systems Biology (ISB), Seattle, Washington 98109, United States
| | - Zhi Sun
- Institute for Systems Biology (ISB), Seattle, Washington 98109, United States
| | - Eric W Deutsch
- Institute for Systems Biology (ISB), Seattle, Washington 98109, United States
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5
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Saeed B, Deligne F, Brillada C, Dünser K, Ditengou FA, Turek I, Allahham A, Grujic N, Dagdas Y, Ott T, Kleine-Vehn J, Vert G, Trujillo M. K63-linked ubiquitin chains are a global signal for endocytosis and contribute to selective autophagy in plants. Curr Biol 2023; 33:1337-1345.e5. [PMID: 36863341 DOI: 10.1016/j.cub.2023.02.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 12/08/2022] [Accepted: 02/07/2023] [Indexed: 03/04/2023]
Abstract
In contrast to other eukaryotic model organisms, the closely related ubiquitin (Ub)-conjugating enzymes UBC35 and UBC36 are the main sources of K63-linked Ub chains in Arabidopsis.1 Although K63-linked chains have been associated with the regulation of vesicle trafficking, definitive proof for their role in endocytosis was missing. We show that the ubc35 ubc36 mutant has pleiotropic phenotypes related to hormone and immune signaling. Specifically, we reveal that ubc35-1 ubc36-1 plants have altered turnover of integral membrane proteins including FLS2, BRI1, and PIN1 at the plasma membrane. Our data indicates that K63-Ub chains are generally required for endocytic trafficking in plants. In addition, we show that in plants K63-Ub chains are involved in selective autophagy through NBR1, the second major pathway delivering cargoes to the vacuole for degradation. Similar to autophagy-defective mutants, ubc35-1 ubc36-1 plants display an accumulation of autophagy markers. Moreover, autophagy receptor NBR1 interacts with K63-Ub chains, which are required for its delivery to the lytic vacuole.2 Together, we show that K63-Ub chains act as a general signal required for the two main pathways delivering cargo to the vacuole and thus, to maintain proteostasis.
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Affiliation(s)
- Bushra Saeed
- Albert-Ludwigs-University Freiburg, Institute for Biology II, Cell Biology, 79104 Freiburg, Germany
| | - Florian Deligne
- Plant Science Research Laboratory (LRSV), UMR5546 CNRS/University Toulouse 3, 31320 Auzeville Tolosane, France
| | - Carla Brillada
- Albert-Ludwigs-University Freiburg, Institute for Biology II, Cell Biology, 79104 Freiburg, Germany
| | - Kai Dünser
- Albert-Ludwigs-University Freiburg, Institute for Biology II, Cell Biology, 79104 Freiburg, Germany
| | - Franck Aniset Ditengou
- Albert-Ludwigs-University Freiburg, Institute for Biology II, Cell Biology, 79104 Freiburg, Germany; Center for Integrative Biological Signalling Studies (CIBSS), University of Freiburg, 79104 Freiburg, Germany; Bio Imaging Core Light Microscopy (BiMiC), Institute for Disease Modeling and Targeted Medicine (IMITATE), Medical Center University of Freiburg, Albert Ludwigs University Freiburg, Breisacher Str. 113, 79106 Freiburg, Germany
| | - Ilona Turek
- Department of Rural Clinical Sciences, La Trobe Rural Health School, La Trobe University, Bendigo, VIC 3552, Australia
| | - Alaa Allahham
- Albert-Ludwigs-University Freiburg, Institute for Biology II, Cell Biology, 79104 Freiburg, Germany
| | - Nenad Grujic
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna BioCenter (VBC), Vienna 1030, Austria
| | - Yasin Dagdas
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna BioCenter (VBC), Vienna 1030, Austria
| | - Thomas Ott
- Albert-Ludwigs-University Freiburg, Institute for Biology II, Cell Biology, 79104 Freiburg, Germany; Center for Integrative Biological Signalling Studies (CIBSS), University of Freiburg, 79104 Freiburg, Germany
| | - Jürgen Kleine-Vehn
- Albert-Ludwigs-University Freiburg, Institute for Biology II, Cell Biology, 79104 Freiburg, Germany; Center for Integrative Biological Signalling Studies (CIBSS), University of Freiburg, 79104 Freiburg, Germany
| | - Grégory Vert
- Plant Science Research Laboratory (LRSV), UMR5546 CNRS/University Toulouse 3, 31320 Auzeville Tolosane, France.
| | - Marco Trujillo
- Albert-Ludwigs-University Freiburg, Institute for Biology II, Cell Biology, 79104 Freiburg, Germany.
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Liu W, Tang X, Fu X, Zhang H, Zhu C, Zhang N, Si H. Functional Characterization of Potato UBC13- UEV1s Genes Required for Ubiquitin Lys63 Chain to Polyubiquitination. Int J Mol Sci 2023; 24:ijms24032412. [PMID: 36768743 PMCID: PMC9917286 DOI: 10.3390/ijms24032412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/18/2023] [Accepted: 01/19/2023] [Indexed: 01/28/2023] Open
Abstract
Ubiquitin-conjugating enzymes (E2s/UBC) are components of the ubiquitin proteasome system (UPS), and the ubiquitin-conjugating enzyme variant (UEV) is one of E2s (ubiquitin-conjugating enzymes, UBC) subfamily. The UEVs and UBC13 play an auxiliary role in mediating Lys63-linked polyUb chain assembly, which is correlated with target protein non-proteolytic functions, such as DNA repair or response to stress. However, the collaborative mechanism of StUBC13 (homologue of AtUBC13) and StUEVs (the UEVs in potato) involved in potato are not fully understood understood. Here, we identified two StUBC13 and seven StUEVs from potato genome. We analyzed protein motif and conserved domain, gene structure, phylogenetic features, cis-acting elements of StUBC13 and StUEVs. Subsequently, we screened StUBC13 partners protein and verified interaction between StUBC13 and StUEVs using yeast two-hybrid, split luciferase complementation (SLC) and bimolecular fluorescence complementation (BiFC) approach. The expression profile and qRT-PCR analysis suggested that StUBC13 and StUEVs gene exhibited a tissue-specific expression and were induced by different stress. Overall, this investigative study provides a comprehensive reference and view for further functional research on StUBC13 and StUEV1s in potato.
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Affiliation(s)
- Weigang Liu
- State Key Laboratory of Aridland Crop Science, Gansu Agricultural University, Lanzhou 730070, China
- College of Agronomy, Gansu Agricultural University, Lanzhou 730070, China
| | - Xun Tang
- State Key Laboratory of Aridland Crop Science, Gansu Agricultural University, Lanzhou 730070, China
- College of Life Science and Technology, Gansu Agricultural University, Lanzhou 730070, China
| | - Xue Fu
- State Key Laboratory of Aridland Crop Science, Gansu Agricultural University, Lanzhou 730070, China
- College of Agronomy, Gansu Agricultural University, Lanzhou 730070, China
| | - Huanhuan Zhang
- State Key Laboratory of Aridland Crop Science, Gansu Agricultural University, Lanzhou 730070, China
- College of Agronomy, Gansu Agricultural University, Lanzhou 730070, China
| | - Cunlan Zhu
- State Key Laboratory of Aridland Crop Science, Gansu Agricultural University, Lanzhou 730070, China
- College of Life Science and Technology, Gansu Agricultural University, Lanzhou 730070, China
| | - Ning Zhang
- State Key Laboratory of Aridland Crop Science, Gansu Agricultural University, Lanzhou 730070, China
- College of Life Science and Technology, Gansu Agricultural University, Lanzhou 730070, China
| | - Huaijun Si
- State Key Laboratory of Aridland Crop Science, Gansu Agricultural University, Lanzhou 730070, China
- College of Life Science and Technology, Gansu Agricultural University, Lanzhou 730070, China
- Correspondence:
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7
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Kumasaruge I, Wen R, Wang L, Gao P, Peng G, Xiao W. Systematic characterization of Brassica napus UBC13 genes involved in DNA-damage response and K63-linked polyubiquitination. BMC PLANT BIOLOGY 2023; 23:24. [PMID: 36631796 PMCID: PMC9835285 DOI: 10.1186/s12870-023-04035-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 01/02/2023] [Indexed: 06/17/2023]
Abstract
BACKGROUND Ubc13 is the only known ubiquitin conjugating enzyme (Ubc/E2) dedicated to promoting Lys (K)63-linked polyubiquitination, and this process requires a Ubc/E2 variant (UEV). Unlike conventional K48-linked polyubiquitination that targets proteins for degradation, K63-linked polyubiquitination, which is involved in several cellular processes, does not target proteins for degradation but alter their activities. RESULTS In this study we report the identification and functional characterization of 12 Brassica napus UBC13 genes. All the cloned UBC13 gene products were able to physically interact with AtUev1D, an Arabidopsis UEV, to form stable complexes that are capable of catalyzing K63-linked polyubiquitination in vitro. Furthermore, BnUBC13 genes functionally complemented the yeast ubc13 null mutant defects in spontaneous mutagenesis and DNA-damage responses, suggesting that BnUBC13s can replace yeast UBC13 in mediating K63-linked polyubiquitination and error-free DNA-damage tolerance. CONCLUSION Collectively, this study provides convincing data to support notions that B. napus Ubc13s promote K63-linked polyubiquitination and are probably required for abiotic stress response. Since plant Ubc13-UEV are also implicated in other developmental and stress responses, this systematic study sets a milestone in exploring roles of K63-linked polyubiquitination in this agriculturally important crop.
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Affiliation(s)
- Ivanthi Kumasaruge
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, SK, S7N 5E5, Canada
| | - Rui Wen
- Saskatoon Research and Development Centre, Agriculture and Agri-Food Canada, Saskatoon, SK, S7N 0X2, Canada
| | - Lipu Wang
- Department of Plant Sciences, University of Saskatchewan, Saskatoon, SK, S7N 5A8, Canada
| | - Peng Gao
- Saskatoon Research and Development Centre, Agriculture and Agri-Food Canada, Saskatoon, SK, S7N 0X2, Canada
| | - Gary Peng
- Saskatoon Research and Development Centre, Agriculture and Agri-Food Canada, Saskatoon, SK, S7N 0X2, Canada
| | - Wei Xiao
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, SK, S7N 5E5, Canada.
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Niemeyer M, Parra JOF, Calderón Villalobos LIA. An In vitro Assay to Recapitulate Hormone-Triggered and SCF-Mediated Protein Ubiquitylation. Methods Mol Biol 2023; 2581:43-56. [PMID: 36413309 DOI: 10.1007/978-1-0716-2784-6_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Signaling proteins trigger a sequence of molecular switches in the cell, which permit development, growth, and rapid adaptation to changing environmental conditions. SCF-type E3 ubiquitin ligases recognize signaling proteins prompting changes in their fate, one of these being ubiquitylation followed by degradation by the proteasome. SCFs together with their ubiquitylation targets (substrates) often serve as phytohormone receptors, responding and/or assembling in response to fluctuating intracellular hormone concentrations. Tracing and understanding phytohormone perception and SCF-mediated ubiquitylation of proteins could provide powerful clues on the molecular mechanisms utilized for plant adaptation. Here, we describe an adaptable in vitro system that uses recombinant proteins and enables the study of hormone-triggered SCF-substrate interaction and the dynamics of protein ubiquitylation. This system can serve to predict the requirements for protein recognition and to understand how phytohormone levels have the power to control protein fate.
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Affiliation(s)
- Michael Niemeyer
- Molecular Signal Processing Department, Leibniz Institute of Plant Biochemistry (IPB), Halle (Saale), Germany
| | - Jhonny Oscar Figueroa Parra
- Molecular Signal Processing Department, Leibniz Institute of Plant Biochemistry (IPB), Halle (Saale), Germany
| | - Luz Irina A Calderón Villalobos
- Molecular Signal Processing Department, Leibniz Institute of Plant Biochemistry (IPB), Halle (Saale), Germany.
- KWS Gateway Research Center, LLC, BRDG Park at the Danforth Plant Science Center, St. Louis, MO, USA.
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9
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Wang L, Yang K, Wang Q, Xiao W. Genetic analysis of DNA-damage tolerance pathways in Arabidopsis. PLANT CELL REPORTS 2023; 42:153-164. [PMID: 36319861 DOI: 10.1007/s00299-022-02942-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 10/20/2022] [Indexed: 06/16/2023]
Abstract
Genetic analysis revealed a two-branch DNA-damage tolerance mechanism in Arabidopsis, namely translesion DNA synthesis and error-free lesion bypass, represented by Rev3 and Rad5a-Uev1C/D, respectively. DNA-damage tolerance (DDT) is a mechanism by which cells complete replication in the presence of replication-blocking lesions. In budding yeast, DDT is achieved through Rad6-Rad18-mediated monoubiquitination of proliferating cell nuclear antigen (PCNA), which promotes translesion DNA synthesis (TLS) and is followed by Ubc13-Mms2-Rad5 mediated K63-linked PCNA polyubiquitination that promotes error-free lesion bypass. Arabidopsis and other known plant genomes contain all of the above homologous genes except RAD18, and whether plants possess an intact DDT mechanism is unclear. In this study, we created Arabidopsis UEV1 (homologous to yeast MMS2) gene mutations and obtained two sets of double mutant lines Atuev1ab and Atuev1cd. It turned out that the Atuev1cd, but not the Atuev1ab mutant, was sensitive to DNA damage. Genetic analyses revealed that AtUEV1C/D and AtRAD5a function in the same pathway, while TLS represented by AtREV3 functions in a separate pathway in response to replication-blocking lesions. Furthermore, unlike budding yeast RAD5 that also functions in the TLS pathway, AtRAD5a is not required for TLS. Observations in this study collectively establish a two-branch DDT model in plants with similarity to and difference from the yeast DDT.
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Affiliation(s)
- Linxiao Wang
- Beijing Key Laboratory of DNA Damage Responses and College of Life Sciences, Capital Normal University, Beijing, 100048, China
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, SK, S7N 5E5, Canada
| | - Kun Yang
- Beijing Key Laboratory of DNA Damage Responses and College of Life Sciences, Capital Normal University, Beijing, 100048, China
| | - Qiuheng Wang
- Beijing Key Laboratory of DNA Damage Responses and College of Life Sciences, Capital Normal University, Beijing, 100048, China
| | - Wei Xiao
- Beijing Key Laboratory of DNA Damage Responses and College of Life Sciences, Capital Normal University, Beijing, 100048, China.
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, SK, S7N 5E5, Canada.
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Wong A, Bi C, Chi W, Hu N, Gehring C. Amino acid motifs for the identification of novel protein interactants. Comput Struct Biotechnol J 2022; 21:326-334. [PMID: 36582434 PMCID: PMC9791077 DOI: 10.1016/j.csbj.2022.12.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 12/06/2022] [Accepted: 12/06/2022] [Indexed: 12/14/2022] Open
Abstract
Biological systems consist of multiple components of different physical and chemical properties that require complex and dynamic regulatory loops to function efficiently. The discovery of ever more novel interacting sites in complex proteins suggests that we are only beginning to understand how cellular and biological functions are integrated and tuned at the molecular and systems levels. Here we review recently discovered interacting sites which have been identified through rationally designed amino acid motifs diagnostic for specific molecular functions, including enzymatic activities and ligand-binding properties. We specifically discuss the nature of the latter using as examples, novel hormone recognition and gas sensing sites that occur in moonlighting protein complexes. Drawing evidence from the current literature, we discuss the potential implications at the cellular, tissue, and/or organismal levels of such non-catalytic interacting sites and provide several promising avenues for the expansion of amino acid motif searches to discover hitherto unknown protein interactants and interaction networks. We believe this knowledge will unearth unexpected functions in both new and well-characterized proteins, thus filling existing conceptual gaps or opening new avenues for applications either as drug targets or tools in pharmacology, cell biology and bio-catalysis. Beyond this, motif searches may also support the design of novel, effective and sustainable approaches to crop improvements and the development of new therapeutics.
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Affiliation(s)
- Aloysius Wong
- Department of Biology, College of Science and Technology, Wenzhou-Kean University, 88 Daxue Road, Ouhai, Wenzhou, Zhejiang Province 325060, China,Wenzhou Municipal Key Lab for Applied Biomedical and Biopharmaceutical Informatics, Ouhai, Wenzhou, Zhejiang Province 325060, China,Zhejiang Bioinformatics International Science and Technology Cooperation Center, Ouhai, Wenzhou, Zhejiang Province 325060, China
| | - Chuyun Bi
- Department of Biology, College of Science and Technology, Wenzhou-Kean University, 88 Daxue Road, Ouhai, Wenzhou, Zhejiang Province 325060, China,Wenzhou Municipal Key Lab for Applied Biomedical and Biopharmaceutical Informatics, Ouhai, Wenzhou, Zhejiang Province 325060, China,Zhejiang Bioinformatics International Science and Technology Cooperation Center, Ouhai, Wenzhou, Zhejiang Province 325060, China
| | - Wei Chi
- Department of Biology, College of Science and Technology, Wenzhou-Kean University, 88 Daxue Road, Ouhai, Wenzhou, Zhejiang Province 325060, China
| | - Ningxin Hu
- Department of Biology, College of Science and Technology, Wenzhou-Kean University, 88 Daxue Road, Ouhai, Wenzhou, Zhejiang Province 325060, China
| | - Chris Gehring
- Department of Chemistry, Biology & Biotechnology, University of Perugia, Perugia 06121, Italy,Corresponding author.
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Spielmann J, Cointry V, Devime F, Ravanel S, Neveu J, Vert G. Differential metal sensing and metal-dependent degradation of the broad spectrum root metal transporter IRT1. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 112:1252-1265. [PMID: 36269689 DOI: 10.1111/tpj.16010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 10/09/2022] [Accepted: 10/13/2022] [Indexed: 06/16/2023]
Abstract
Iron is an essential micronutrient for plant growth and development. Under low iron conditions, Arabidopsis plants take up soil iron using the root iron transporter IRT1. In addition to iron, IRT1 also transports others divalent metals, including cadmium, which consequently accumulates into plant tissues and enters the food chain. IRT1 expression was shown to be regulated at the transcriptional and post-translational levels by its essential metal substrates to maximize iron uptake while limiting the accumulation of zinc, manganese, or cobalt. Here, we characterized the regulation of IRT1 by cadmium. A short-term exposure to cadmium decreased the cell surface levels of IRT1 through endocytosis and degradation, but with a lower efficiency than observed for other IRT1 metal substrates. We demonstrated that IRT1 endocytosis in response to cadmium is mediated through the direct binding of cadmium to histidine residues within the regulatory loop of IRT1. However, we revealed that the affinity of the metal sensing motif is much lower for cadmium compared to other metal substrates of IRT1. Finally, we proved that cadmium-induced IRT1 degradation takes place through ubiquitin-mediated endocytosis driven by the UBC35/36 E2 ubiquitin-conjugating enzymes and the IDF1 E3 ubiquitin ligase. Altogether, this work sheds light on the mechanisms of cadmium-mediated downregulation of IRT1 and provides an additional molecular basis for cadmium accumulation and toxicity in plants.
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Affiliation(s)
- Julien Spielmann
- Plant Science Research Laboratory (LRSV), UMR5546 CNRS/Université Toulouse 3/Toulouse-INP, 24 chemin de Borde Rouge, 31320, Auzeville Tolosane, France
| | - Virginia Cointry
- Plant Science Research Laboratory (LRSV), UMR5546 CNRS/Université Toulouse 3/Toulouse-INP, 24 chemin de Borde Rouge, 31320, Auzeville Tolosane, France
| | - Fabienne Devime
- University of Grenoble Alpes, CEA, INRA, CNRS, IRIG, PCV, 17 Avenue des Martyrs, 38000, Grenoble, France
| | - Stéphane Ravanel
- University of Grenoble Alpes, CEA, INRA, CNRS, IRIG, PCV, 17 Avenue des Martyrs, 38000, Grenoble, France
| | - Julie Neveu
- Plant Science Research Laboratory (LRSV), UMR5546 CNRS/Université Toulouse 3/Toulouse-INP, 24 chemin de Borde Rouge, 31320, Auzeville Tolosane, France
| | - Grégory Vert
- Plant Science Research Laboratory (LRSV), UMR5546 CNRS/Université Toulouse 3/Toulouse-INP, 24 chemin de Borde Rouge, 31320, Auzeville Tolosane, France
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12
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Grones P, De Meyer A, Pleskot R, Mylle E, Kraus M, Vandorpe M, Yperman K, Eeckhout D, Dragwidge JM, Jiang Q, Nolf J, Pavie B, De Jaeger G, De Rybel B, Van Damme D. The endocytic TPLATE complex internalizes ubiquitinated plasma membrane cargo. NATURE PLANTS 2022; 8:1467-1483. [PMID: 36456802 PMCID: PMC7613989 DOI: 10.1038/s41477-022-01280-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 10/19/2022] [Indexed: 05/12/2023]
Abstract
Endocytosis controls the perception of stimuli by modulating protein abundance at the plasma membrane. In plants, clathrin-mediated endocytosis is the most prominent internalization pathway and relies on two multimeric adaptor complexes, the AP-2 and the TPLATE complex (TPC). Ubiquitination is a well-established modification triggering endocytosis of cargo proteins, but how this modification is recognized to initiate the endocytic event remains elusive. Here we show that TASH3, one of the large subunits of TPC, recognizes ubiquitinated cargo at the plasma membrane via its SH3 domain-containing appendage. TASH3 lacking this evolutionary specific appendage modification allows TPC formation but the plants show severely reduced endocytic densities, which correlates with reduced endocytic flux. Moreover, comparative plasma membrane proteomics identified differential accumulation of multiple ubiquitinated cargo proteins for which we confirm altered trafficking. Our findings position TPC as a key player for ubiquitinated cargo internalization, allowing future identification of target proteins under specific stress conditions.
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Affiliation(s)
- Peter Grones
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium.
- Center for Plant Systems Biology, VIB, Ghent, Belgium.
| | - Andreas De Meyer
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - Roman Pleskot
- Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Evelien Mylle
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - Michael Kraus
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - Michael Vandorpe
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - Klaas Yperman
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Ghent, Belgium
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Dominique Eeckhout
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - Jonathan Michael Dragwidge
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - Qihang Jiang
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - Jonah Nolf
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - Benjamin Pavie
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
- BioImaging Core, VIB, 9052 Ghent, Belgium
| | - Geert De Jaeger
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - Bert De Rybel
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - Daniël Van Damme
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium.
- Center for Plant Systems Biology, VIB, Ghent, Belgium.
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13
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Arabidopsis Ubiquitin-Conjugating Enzymes UBC4, UBC5, and UBC6 Have Major Functions in Sugar Metabolism and Leaf Senescence. Int J Mol Sci 2022; 23:ijms231911143. [PMID: 36232444 PMCID: PMC9569852 DOI: 10.3390/ijms231911143] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 09/15/2022] [Accepted: 09/19/2022] [Indexed: 11/23/2022] Open
Abstract
The ubiquitin-conjugating enzyme (E2) is required for protein ubiquitination. Arabidopsis has 37 E2s grouped into 14 subfamilies and the functions for many of them are unknown. We utilized genetic and biochemical methods to study the roles of Arabidopsis UBC4, UBC5, and UBC6 of the E2 subfamily IV. The Arabidopsis ubc4/5/6 triple mutant plants had higher levels of glucose, sucrose, and starch than the control plants, as well as a higher protein level of a key gluconeogenic enzyme, cytosolic fructose 1,6-bisphosphatase 1 (cyFBP). In an in vitro assay, the proteasome inhibitor MG132 inhibited the degradation of recombinant cyFBP whereas ATP promoted cyFBP degradation. In the quadruple mutant ubc4/5/6 cyfbp, the sugar levels returned to normal, suggesting that the increased sugar levels in the ubc4/5/6 mutant were due to an increased cyFBPase level. In addition, the ubc4/5/6 mutant plants showed early leaf senescence at late stages of plant development as well as accelerated leaf senescence using detached leaves. Further, the leaf senescence phenotype remained in the quadruple ubc4/5/6 cyfbp mutant. Our results suggest that UBC4/5/6 have two lines of important functions, in sugar metabolism through regulating the cyFBP protein level and in leaf senescence likely through a cyFBP-independent mechanism.
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14
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Yang K, Xiao W. Functions and mechanisms of the Ubc13-UEV complex and lysine 63-linked polyubiquitination in plants. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:5372-5387. [PMID: 35640002 DOI: 10.1093/jxb/erac239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 05/24/2022] [Indexed: 06/15/2023]
Abstract
Ubiquitination is one of the best-known post-translational modifications in eukaryotes, in which different linkage types of polyubiquitination result in different outputs of the target proteins. Distinct from the well-characterized K48-linked polyubiquitination that usually serves as a signal for degradation of the target protein, K63-linked polyubiquitination often requires a unique E2 heterodimer Ubc13-UEV and alters the target protein activity instead of marking it for degradation. This review focuses on recent advances on the roles of Ubc13-UEV-mediated K63-linked polyubiquitination in plant growth, development, and response to environmental stresses.
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Affiliation(s)
- Kun Yang
- Beijing Key Laboratory of DNA Damage Responses and College of Life Sciences, Capital Normal University, Beijing, China
| | - Wei Xiao
- Beijing Key Laboratory of DNA Damage Responses and College of Life Sciences, Capital Normal University, Beijing, China
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, SK, Canada
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15
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Harnessing the ubiquitin code to respond to environmental cues. Essays Biochem 2022; 66:111-121. [PMID: 35880291 PMCID: PMC9400065 DOI: 10.1042/ebc20210094] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 06/13/2022] [Accepted: 06/27/2022] [Indexed: 12/15/2022]
Abstract
Ubiquitination is an essential post-translational signal that allows cells to adapt and respond to environmental stimuli. Substrate modifications range from a single ubiquitin molecule to complex polyubiquitin chains, where diverse chain topologies constitute a code that is utilized to modify the functions of proteins in numerous cellular signalling pathways. Diverse ubiquitin chain topologies are generated by linking the C-terminus of ubiquitin to one of seven lysine residues or the N-terminal methionine 1 residue of the preceding ubiquitin. Cooperative action between a large array of E2 conjugating and E3 ligase enzymes supports the formation of not only homotypic ubiquitin chains but also heterotypic mixed or branched chains. This complex array of chain topologies is recognized by proteins containing linkage-specific ubiquitin-binding domains and regulates numerous cellular pathways. Although many functions of the ubiquitin code in plants remain unknown, recent work suggests that specific chain topologies are associated with particular molecular processes. Deciphering the ubiquitin code and how plants utilize it to cope with the changing environment is essential to understand the regulatory mechanisms that underpin myriad stress responses and establishment of environmental tolerance.
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16
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E2 ubiquitin-conjugating enzymes (UBCs): drivers of ubiquitin signalling in plants. Essays Biochem 2022; 66:99-110. [PMID: 35766526 DOI: 10.1042/ebc20210093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 06/10/2022] [Accepted: 06/13/2022] [Indexed: 12/22/2022]
Abstract
Most research in the field of ubiquitination has focused on E3 ubiquitin ligases because they are the specificity determinants of the ubiquitination process. Nevertheless, E2s are responsible for the catalysis during ubiquitin transfer, and are therefore, at the heart of the ubiquitination process. Arabidopsis has 37 ubiquitin E2s with additional ones mediating the attachment of ubiquitin-like proteins (e.g. SUMO, Nedd8 and ATG8). Importantly, E2s largely determine the type of ubiquitin chain built, and therefore, the type of signal that decides over the fate of the modified protein, such as degradation by the proteasome (Lys48-linked ubiquitin chains) or relocalization (Lys63-linked ubiquitin chains). Moreover, new regulatory layers impinging on E2s activity, including post-translational modifications or cofactors, are emerging that highlight the importance of E2s.
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17
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Retzer K, Moulinier-Anzola J, Lugsteiner R, Konstantinova N, Schwihla M, Korbei B, Luschnig C. Endosomally Localized RGLG-Type E3 RING-Finger Ligases Modulate Sorting of Ubiquitylation-Mimic PIN2. Int J Mol Sci 2022; 23:6767. [PMID: 35743207 PMCID: PMC9224344 DOI: 10.3390/ijms23126767] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 03/07/2022] [Accepted: 06/14/2022] [Indexed: 11/26/2022] Open
Abstract
Intracellular sorting and the abundance of sessile plant plasma membrane proteins are imperative for sensing and responding to environmental inputs. A key determinant for inducing adjustments in protein localization and hence functionality is their reversible covalent modification by the small protein modifier ubiquitin, which is for example responsible for guiding proteins from the plasma membrane to endosomal compartments. This mode of membrane protein sorting control requires the catalytic activity of E3 ubiquitin ligases, amongst which members of the RING DOMAIN LIGASE (RGLG) family have been implicated in the formation of lysine 63-linked polyubiquitin chains, serving as a prime signal for endocytic vacuolar cargo sorting. Nevertheless, except from some indirect implications for such RGLG activity, no further evidence for their role in plasma membrane protein sorting has been provided so far. Here, by employing RGLG1 reporter proteins combined with assessment of plasma membrane protein localization in a rglg1 rglg2 loss-of-function mutant, we demonstrate a role for RGLGs in cargo trafficking between plasma membrane and endosomal compartments. Specifically, our findings unveil a requirement for RGLG1 association with endosomal sorting compartments for fundamental aspects of plant morphogenesis, underlining a vital importance for ubiquitylation-controlled intracellular sorting processes.
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Affiliation(s)
| | | | | | | | | | - Barbara Korbei
- Department of Applied Genetics and Cell Biology, Institute of Molecular Plant Biology, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria; (K.R.); (J.M.-A.); (R.L.); (N.K.); (M.S.)
| | - Christian Luschnig
- Department of Applied Genetics and Cell Biology, Institute of Molecular Plant Biology, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria; (K.R.); (J.M.-A.); (R.L.); (N.K.); (M.S.)
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18
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Ubiquitin ligases at the nexus of plant responses to biotic and abiotic stresses. Essays Biochem 2022; 66:123-133. [PMID: 35704617 DOI: 10.1042/ebc20210070] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Revised: 05/11/2022] [Accepted: 05/30/2022] [Indexed: 01/15/2023]
Abstract
Plants must cope with an ever-changing environment, including concurrent biotic and abiotic stresses. The ubiquitin-proteasome system (UPS) is intricately involved in regulating signaling events that facilitate cellular changes required to mitigate the detrimental effects of environmental stress. A key component of the UPS are ubiquitin ligases (or E3s) that catalyze the attachment of ubiquitin molecules to select substrate proteins, which are then recognized by the 26S proteasome for degradation. With the identification of substrate proteins, a growing number of E3s are shown to differentially regulate responses to abiotic as well as bioitic stresses. The review discusses select E3s to illustrate the role of ubiquitin ligases as negative and/or positive regulators of responses to both biotic and abiotic stresses.
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19
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Le XH, Lee CP, Monachello D, Millar AH. Metabolic evidence for distinct pyruvate pools inside plant mitochondria. NATURE PLANTS 2022; 8:694-705. [PMID: 35681019 DOI: 10.1038/s41477-022-01165-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 05/04/2022] [Indexed: 06/15/2023]
Abstract
The majority of the pyruvate inside plant mitochondria is either transported into the matrix from the cytosol via the mitochondria pyruvate carrier (MPC) or synthesized in the matrix by alanine aminotransferase (AlaAT) or NAD-malic enzyme (NAD-ME). Pyruvate from these origins could mix into a single pool in the matrix and contribute indistinguishably to respiration via the pyruvate dehydrogenase complex (PDC), or these molecules could maintain a degree of independence in metabolic regulation. Here we demonstrate that feeding isolated mitochondria with uniformly labelled 13C-pyruvate and unlabelled malate enables the assessment of pyruvate contribution from different sources to intermediate production in the tricarboxylic acid cycle. Imported pyruvate was the preferred source for citrate production even when the synthesis of NAD-ME-derived pyruvate was optimized. Genetic or pharmacological elimination of MPC activity removed this preference and allowed an equivalent amount of citrate to be generated from the pyruvate produced by NAD-ME. Increasing the mitochondrial pyruvate pool size by exogenous addition affected only metabolites from pyruvate transported by MPC, whereas depleting the pyruvate pool size by transamination to alanine affected only metabolic products derived from NAD-ME. PDC was more membrane-associated than AlaAT and NAD-ME, suggesting that the physical organization of metabolic machinery may influence metabolic rates. Together, these data reveal that the respiratory substrate supply in plants involves distinct pyruvate pools inside the matrix that can be flexibly mixed on the basis of the rate of pyruvate transport from the cytosol. These pools are independently regulated and contribute differentially to organic acid export from plant mitochondria.
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Affiliation(s)
- Xuyen H Le
- School of Molecular Sciences, The University of Western Australia, Perth, WA, Australia
- The ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, Perth, WA, Australia
| | - Chun Pong Lee
- School of Molecular Sciences, The University of Western Australia, Perth, WA, Australia
- The ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, Perth, WA, Australia
| | - Dario Monachello
- Université Paris-Saclay, CNRS, INRAE, Univ Evry, Institute of Plant Sciences Paris-Saclay (IPS2), Orsay, France
- Université de Paris, CNRS, INRAE, Institute of Plant Sciences Paris-Saclay (IPS2), Orsay, France
| | - A Harvey Millar
- School of Molecular Sciences, The University of Western Australia, Perth, WA, Australia.
- The ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, Perth, WA, Australia.
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20
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Trenner J, Monaghan J, Saeed B, Quint M, Shabek N, Trujillo M. Evolution and Functions of Plant U-Box Proteins: From Protein Quality Control to Signaling. ANNUAL REVIEW OF PLANT BIOLOGY 2022; 73:93-121. [PMID: 35226816 DOI: 10.1146/annurev-arplant-102720-012310] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Posttranslational modifications add complexity and diversity to cellular proteomes. One of the most prevalent modifications across eukaryotes is ubiquitination, which is orchestrated by E3 ubiquitin ligases. U-box-containing E3 ligases have massively expanded in the plant kingdom and have diversified into plant U-box proteins (PUBs). PUBs likely originated from two or three ancestral forms, fusing with diverse functional subdomains that resulted in neofunctionalization. Their emergence and diversification may reflect adaptations to stress during plant evolution, reflecting changes in the needs of plant proteomes to maintain cellular homeostasis. Through their close association with protein kinases, they are physically linked to cell signaling hubs and activate feedback loops by dynamically pairing with E2-ubiquitin-conjugating enzymes to generate distinct ubiquitin polymers that themselves act as signals. Here, we complement current knowledgewith comparative genomics to gain a deeper understanding of PUB function, focusing on their evolution and structural adaptations of key U-box residues, as well as their various roles in plant cells.
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Affiliation(s)
- Jana Trenner
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Halle, Germany; ,
| | | | - Bushra Saeed
- Institute of Biology II, Faculty of Biology, Albert-Ludwigs-University Freiburg, Freiburg, Germany; ,
| | - Marcel Quint
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Halle, Germany; ,
| | - Nitzan Shabek
- Department of Plant Biology, College of Biological Sciences, University of California, Davis, California, USA;
| | - Marco Trujillo
- Institute of Biology II, Faculty of Biology, Albert-Ludwigs-University Freiburg, Freiburg, Germany; ,
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21
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Hasegawa Y, Huarancca Reyes T, Uemura T, Baral A, Fujimaki A, Luo Y, Morita Y, Saeki Y, Maekawa S, Yasuda S, Mukuta K, Fukao Y, Tanaka K, Nakano A, Takagi J, Bhalerao RP, Yamaguchi J, Sato T. The TGN/EE SNARE protein SYP61 and the ubiquitin ligase ATL31 cooperatively regulate plant responses to carbon/nitrogen conditions in Arabidopsis. THE PLANT CELL 2022; 34:1354-1374. [PMID: 35089338 PMCID: PMC8972251 DOI: 10.1093/plcell/koac014] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 12/30/2021] [Indexed: 05/23/2023]
Abstract
Ubiquitination is a post-translational modification involving the reversible attachment of the small protein ubiquitin to a target protein. Ubiquitination is involved in numerous cellular processes, including the membrane trafficking of cargo proteins. However, the ubiquitination of the trafficking machinery components and their involvement in environmental responses are not well understood. Here, we report that the Arabidopsis thaliana trans-Golgi network/early endosome localized SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) protein SYP61 interacts with the transmembrane ubiquitin ligase ATL31, a key regulator of resistance to disrupted carbon (C)/nitrogen/(N)-nutrient conditions. SYP61 is a key component of membrane trafficking in Arabidopsis. The subcellular localization of ATL31 was disrupted in knockdown mutants of SYP61, and the insensitivity of ATL31-overexpressing plants to high C/low N-stress was repressed in these mutants, suggesting that SYP61 and ATL31 cooperatively function in plant responses to nutrient stress. SYP61 is ubiquitinated in plants, and its ubiquitination level is upregulated under low C/high N-nutrient conditions. These findings provide important insights into the ubiquitin signaling and membrane trafficking machinery in plants.
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Affiliation(s)
- Yoko Hasegawa
- Faculty of Science and Graduate School of Life Science, Hokkaido University, Kita-ku N10-W8, Sapporo 060-0810, Japan
| | - Thais Huarancca Reyes
- Faculty of Science and Graduate School of Life Science, Hokkaido University, Kita-ku N10-W8, Sapporo 060-0810, Japan
| | - Tomohiro Uemura
- Graduate School of Humanities and Sciences, Ochanomizu University, Bunkyo-ku, Tokyo 112-8610, Japan
| | - Anirban Baral
- Umeå Plant Science Centre, Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå S-901 83, Sweden
| | - Akari Fujimaki
- Faculty of Science and Graduate School of Life Science, Hokkaido University, Kita-ku N10-W8, Sapporo 060-0810, Japan
| | - Yongming Luo
- Faculty of Science and Graduate School of Life Science, Hokkaido University, Kita-ku N10-W8, Sapporo 060-0810, Japan
| | - Yoshie Morita
- Faculty of Science and Graduate School of Life Science, Hokkaido University, Kita-ku N10-W8, Sapporo 060-0810, Japan
| | - Yasushi Saeki
- Laboratory of Protein Metabolism, Tokyo Metropolitan Institute of Medical Science, Setagaya-ku, Tokyo 156-8506, Japan
| | - Shugo Maekawa
- Faculty of Science and Graduate School of Life Science, Hokkaido University, Kita-ku N10-W8, Sapporo 060-0810, Japan
| | - Shigetaka Yasuda
- Faculty of Science and Graduate School of Life Science, Hokkaido University, Kita-ku N10-W8, Sapporo 060-0810, Japan
| | - Koki Mukuta
- Faculty of Science and Graduate School of Life Science, Hokkaido University, Kita-ku N10-W8, Sapporo 060-0810, Japan
| | - Yoichiro Fukao
- Department of Bioinformatics, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan
| | - Keiji Tanaka
- Laboratory of Protein Metabolism, Tokyo Metropolitan Institute of Medical Science, Setagaya-ku, Tokyo 156-8506, Japan
| | - Akihiko Nakano
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, Wako, Saitama 351-0198, Japan
| | - Junpei Takagi
- Faculty of Science and Graduate School of Life Science, Hokkaido University, Kita-ku N10-W8, Sapporo 060-0810, Japan
| | - Rishikesh P Bhalerao
- Umeå Plant Science Centre, Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå S-901 83, Sweden
| | - Junji Yamaguchi
- Faculty of Science and Graduate School of Life Science, Hokkaido University, Kita-ku N10-W8, Sapporo 060-0810, Japan
| | - Takeo Sato
- Faculty of Science and Graduate School of Life Science, Hokkaido University, Kita-ku N10-W8, Sapporo 060-0810, Japan
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22
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Berger N, Demolombe V, Hem S, Rofidal V, Steinmann L, Krouk G, Crabos A, Nacry P, Verdoucq L, Santoni V. Root Membrane Ubiquitinome under Short-Term Osmotic Stress. Int J Mol Sci 2022; 23:ijms23041956. [PMID: 35216074 PMCID: PMC8879470 DOI: 10.3390/ijms23041956] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 02/04/2022] [Accepted: 02/07/2022] [Indexed: 01/27/2023] Open
Abstract
Osmotic stress can be detrimental to plants, whose survival relies heavily on proteomic plasticity. Protein ubiquitination is a central post-translational modification in osmotic-mediated stress. In this study, we used the K-Ɛ-GG antibody enrichment method integrated with high-resolution mass spectrometry to compile a list of 719 ubiquitinated lysine (K-Ub) residues from 450 Arabidopsis root membrane proteins (58% of which are transmembrane proteins), thereby adding to the database of ubiquitinated substrates in plants. Although no ubiquitin (Ub) motifs could be identified, the presence of acidic residues close to K-Ub was revealed. Our ubiquitinome analysis pointed to a broad role of ubiquitination in the internalization and sorting of cargo proteins. Moreover, the simultaneous proteome and ubiquitinome quantification showed that ubiquitination is mostly not involved in membrane protein degradation in response to short osmotic treatment but that it is putatively involved in protein internalization, as described for the aquaporin PIP2;1. Our in silico analysis of ubiquitinated proteins shows that two E2 Ub-conjugating enzymes, UBC32 and UBC34, putatively target membrane proteins under osmotic stress. Finally, we revealed a positive role for UBC32 and UBC34 in primary root growth under osmotic stress.
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Affiliation(s)
- Nathalie Berger
- BPMP, CNRS, INRAE, Institut Agro, University Montpellier, 34060 Montpellier, France; (N.B.); (V.D.); (S.H.); (V.R.); (L.S.); (G.K.); (A.C.); (P.N.); (L.V.)
| | - Vincent Demolombe
- BPMP, CNRS, INRAE, Institut Agro, University Montpellier, 34060 Montpellier, France; (N.B.); (V.D.); (S.H.); (V.R.); (L.S.); (G.K.); (A.C.); (P.N.); (L.V.)
| | - Sonia Hem
- BPMP, CNRS, INRAE, Institut Agro, University Montpellier, 34060 Montpellier, France; (N.B.); (V.D.); (S.H.); (V.R.); (L.S.); (G.K.); (A.C.); (P.N.); (L.V.)
| | - Valérie Rofidal
- BPMP, CNRS, INRAE, Institut Agro, University Montpellier, 34060 Montpellier, France; (N.B.); (V.D.); (S.H.); (V.R.); (L.S.); (G.K.); (A.C.); (P.N.); (L.V.)
| | - Laura Steinmann
- BPMP, CNRS, INRAE, Institut Agro, University Montpellier, 34060 Montpellier, France; (N.B.); (V.D.); (S.H.); (V.R.); (L.S.); (G.K.); (A.C.); (P.N.); (L.V.)
- Center for Computational and Theoretical Biology, University of Würzburg, 97070 Würzburg, Germany
| | - Gabriel Krouk
- BPMP, CNRS, INRAE, Institut Agro, University Montpellier, 34060 Montpellier, France; (N.B.); (V.D.); (S.H.); (V.R.); (L.S.); (G.K.); (A.C.); (P.N.); (L.V.)
| | - Amandine Crabos
- BPMP, CNRS, INRAE, Institut Agro, University Montpellier, 34060 Montpellier, France; (N.B.); (V.D.); (S.H.); (V.R.); (L.S.); (G.K.); (A.C.); (P.N.); (L.V.)
| | - Philippe Nacry
- BPMP, CNRS, INRAE, Institut Agro, University Montpellier, 34060 Montpellier, France; (N.B.); (V.D.); (S.H.); (V.R.); (L.S.); (G.K.); (A.C.); (P.N.); (L.V.)
| | - Lionel Verdoucq
- BPMP, CNRS, INRAE, Institut Agro, University Montpellier, 34060 Montpellier, France; (N.B.); (V.D.); (S.H.); (V.R.); (L.S.); (G.K.); (A.C.); (P.N.); (L.V.)
| | - Véronique Santoni
- BPMP, CNRS, INRAE, Institut Agro, University Montpellier, 34060 Montpellier, France; (N.B.); (V.D.); (S.H.); (V.R.); (L.S.); (G.K.); (A.C.); (P.N.); (L.V.)
- Correspondence:
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23
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Trujillo M. Ubiquitination and PARylation cross-talk about immunity. MOLECULAR PLANT 2021; 14:1976-1978. [PMID: 34813951 DOI: 10.1016/j.molp.2021.11.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 11/16/2021] [Accepted: 11/16/2021] [Indexed: 06/13/2023]
Affiliation(s)
- Marco Trujillo
- Faculty of Biology, Cell Biology II, University of Freiburg, 79104 Freiburg, Germany
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24
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Yao D, Arguez MA, He P, Bent AF, Song J. Coordinated regulation of plant immunity by poly(ADP-ribosyl)ation and K63-linked ubiquitination. MOLECULAR PLANT 2021; 14:2088-2103. [PMID: 34418551 PMCID: PMC9070964 DOI: 10.1016/j.molp.2021.08.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 05/24/2021] [Accepted: 08/15/2021] [Indexed: 05/02/2023]
Abstract
Poly(ADP-ribosyl)ation (PARylation) is a posttranslational modification reversibly catalyzed by poly(ADP-ribose) polymerases (PARPs) and poly(ADP-ribose) glycohydrolases (PARGs) and plays a key role in multiple cellular processes. The molecular mechanisms by which PARylation regulates innate immunity remain largely unknown in eukaryotes. Here we show that Arabidopsis UBC13A and UBC13B, the major drivers of lysine 63 (K63)-linked polyubiquitination, directly interact with PARPs/PARGs. Activation of pathogen-associated molecular pattern (PAMP)-triggered immunity promotes these interactions and enhances PARylation of UBC13. Both parp1 parp2 and ubc13a ubc13b mutants are compromised in immune responses with increased accumulation of total pathogenesis-related (PR) proteins but decreased accumulation of secreted PR proteins. Protein disulfide-isomerases (PDIs), essential components of endoplasmic reticulum quality control (ERQC) that ensure proper folding and maturation of proteins destined for secretion, complex with PARPs/PARGs and are PARylated upon PAMP perception. Significantly, PARylation of UBC13 regulates K63-linked ubiquitination of PDIs, which may further promote their disulfide isomerase activities for correct protein folding and subsequent secretion. Taken together, these results indicate that plant immunity is coordinately regulated by PARylation and K63-linked ubiquitination.
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Affiliation(s)
- Dongsheng Yao
- Texas A&M AgriLife Research Center at Dallas, Texas A&M University System, Dallas, TX 75252, USA
| | - Marcus A Arguez
- Texas A&M AgriLife Research Center at Dallas, Texas A&M University System, Dallas, TX 75252, USA
| | - Ping He
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA
| | - Andrew F Bent
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Junqi Song
- Texas A&M AgriLife Research Center at Dallas, Texas A&M University System, Dallas, TX 75252, USA; Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX 77843, USA.
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25
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Wang Y, Cheng X, Yang T, Su Y, Lin S, Zhang S, Zhang Z. Nitrogen-Regulated Theanine and Flavonoid Biosynthesis in Tea Plant Roots: Protein-Level Regulation Revealed by Multiomics Analyses. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:10002-10016. [PMID: 34406741 DOI: 10.1021/acs.jafc.1c02589] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Theanine and flavonoids (especially proanthocyanidins) are the most important and abundant secondary metabolites synthesized in the roots of tea plants. Nitrogen promotes theanine and represses flavonoid biosynthesis in tea plant roots, but the underlying mechanism is still elusive. Here, we analyzed theanine and flavonoid metabolism in tea plant roots under nitrogen deficiency and explored the regulatory mechanism using proteome and ubiquitylome profiling together with transcriptome data. Differentially expressed proteins responsive to nitrogen deficiency were identified and found to be enriched in flavonoid, nitrogen, and amino acid metabolism pathways. The proteins responding to nitrogen deficiency at the transcriptional level, translational level, and both transcriptional and translational levels were classified. Nitrogen-deficiency-responsive and ubiquitinated proteins were further identified. Our results showed that most genes encoding enzymes in the theanine synthesis pathway, such as CsAlaDC, CsGDH, and CsGOGATs, were repressed by nitrogen deficiency at transcriptional and/or protein level(s). While a large number of enzymes in flavonoid metabolism were upregulated at the transcriptional and/or translational level(s). Importantly, the ubiquitylomic analysis identified important proteins, especially the hub enzymes in theanine and flavonoid biosynthesis, such as CsAlaDC, CsTSI, CsGS, CsPAL, and CsCHS, modified by ubiquitination. This study provided novel insights into the regulation of theanine and flavonoid biosynthesis and will contribute to future studies on the post-translational regulation of secondary metabolism in tea plants.
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Affiliation(s)
- Yan Wang
- State Key Laboratory of Tea Biology and Utilization, Anhui Agricultural University, Hefei, Anhui 230036, People's Republic of China
| | - Xunmin Cheng
- State Key Laboratory of Tea Biology and Utilization, Anhui Agricultural University, Hefei, Anhui 230036, People's Republic of China
| | - Tianyuan Yang
- State Key Laboratory of Tea Biology and Utilization, Anhui Agricultural University, Hefei, Anhui 230036, People's Republic of China
| | - Yanlei Su
- State Key Laboratory of Tea Biology and Utilization, Anhui Agricultural University, Hefei, Anhui 230036, People's Republic of China
| | - Shijia Lin
- State Key Laboratory of Tea Biology and Utilization, Anhui Agricultural University, Hefei, Anhui 230036, People's Republic of China
| | - Shupei Zhang
- State Key Laboratory of Tea Biology and Utilization, Anhui Agricultural University, Hefei, Anhui 230036, People's Republic of China
| | - Zhaoliang Zhang
- State Key Laboratory of Tea Biology and Utilization, Anhui Agricultural University, Hefei, Anhui 230036, People's Republic of China
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26
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Trujillo M. Ubiquitin signalling: controlling the message of surface immune receptors. THE NEW PHYTOLOGIST 2021; 231:47-53. [PMID: 33792068 DOI: 10.1111/nph.17360] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 02/25/2021] [Indexed: 05/27/2023]
Abstract
Microbial attack is first detected by immune receptors located at the plasma membrane. Their activation triggers a plethora of signalling cascades that culminate in the immune response. Ubiquitin and ubiquitin-like protein modifiers play key roles in controlling signalling amplitude and intensity, as well as in buffering proteome imbalances caused by pathogen attack. Here I highlight some of the important advances in the field, which are starting to reveal an intertwined and complex signalling circuitry, which regulates cellular dynamics and protein degradation to maintain homeostasis.
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Affiliation(s)
- Marco Trujillo
- Faculty of Biology, Cell Biology, University of Freiburg, Freiburg, 79104, Germany
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27
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Spielmann J, Vert G. The many facets of protein ubiquitination and degradation in plant root iron-deficiency responses. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:2071-2082. [PMID: 32945865 DOI: 10.1093/jxb/eraa441] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 09/16/2020] [Indexed: 06/11/2023]
Abstract
Organisms need to deal with the absolute requirement for metals and also their possible toxicity. This is achieved through an intricate network of signaling pathways that are integrated to ultimately fine-tune iron uptake and metabolism. The mechanisms by which plants cope with iron limitation and the associated genomic responses are well characterized. On top of this transcriptional cascade is another level of regulation involving the post-translational protein modification and degradation. The ubiquitination and/or degradation of several transcription factors in the iron-deficiency signaling pathways and metal transporters has recently come to light. In this review we discuss the mechanisms and possible roles of protein modification and turnover in the regulation of root iron-deficiency responses. We also highlight the tight coupling between metal sensing by E3 ubiquitin ligases or bifunctional transporters and protein degradation.
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Affiliation(s)
- Julien Spielmann
- Plant Science Research Laboratory (LRSV), UMR5546 CNRS/Université Toulouse 3, 24 chemin de Borde Rouge, Auzeville-Tolosane, France
| | - Grégory Vert
- Plant Science Research Laboratory (LRSV), UMR5546 CNRS/Université Toulouse 3, 24 chemin de Borde Rouge, Auzeville-Tolosane, France
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28
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Yapa MM, Yu P, Liao F, Moore AG, Hua Z. Generation of a fertile ask1 mutant uncovers a comprehensive set of SCF-mediated intracellular functions. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 104:493-509. [PMID: 33543567 DOI: 10.1111/tpj.14939] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 07/09/2020] [Indexed: 06/12/2023]
Abstract
Many eukaryotic intracellular processes employ protein ubiquitylation by ubiquitin E3 ligases for functional regulation or protein quality control. In plants, the multi-subunit Skp1-Cullin1-F-box (SCF) complexes compose the largest group of E3 ligases whose specificity is determined by a diverse array of F-box proteins. Although both sequence divergence and polymorphism of F-box genes well support a broad spectrum of SCF functions, experimental evidence is scarce due to the low number of identified SCF substrates. Taking advantage of the bridge role of Skp1 between F-box and Cullin1 in the complex, we systematically analyzed the functional influence of a well-characterized Arabidopsis Skp1-Like1 (ASK1) Ds insertion allele, ask1, in different Arabidopsis accessions. Through 10 generations of backcrossing with Columbia-0 (Col-0), we partially rescued the fertility of this otherwise sterile ask1 allele in Landsberg erecta, thus providing experimental evidence showing the polymorphic roles of SCF complexes. This ask1 mutant produces twisted rosette leaves, a reduced number of petals, fewer viable pollen grains, and larger embryos and seeds compared to Col-0. RNA-Seq-based transcriptome analysis of ask1 uncovered a large spectrum of SCF functions, which is greater than a 10-fold increase compared with previous studies. We also identified its hyposensitive responses to auxin and abscisic acid treatments and enhanced far-red light/phyA-mediated photomorphogenesis. Such diverse roles are consistent with the 20-30% reduction of ubiquitylation events in ask1 estimated by immunoblotting analysis in this work. Collectively, we conclude that ASK1 is a predominant Skp1 protein in Arabidopsis and that the fertile ask1 mutant allowed us to uncover a comprehensive set of SCF functions.
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Affiliation(s)
- Madhura M Yapa
- Department of Environmental and Plant Biology, Ohio University, Athens, Ohio, 45701, USA
| | - Peifeng Yu
- Department of Environmental and Plant Biology, Ohio University, Athens, Ohio, 45701, USA
- Interdisciplinary Program in Molecular and Cellular Biology, Ohio University, Athens, Ohio, 45701, USA
| | - Fanglei Liao
- Department of Environmental and Plant Biology, Ohio University, Athens, Ohio, 45701, USA
- College of Chemistry and Life Science, Zhejiang Normal University, Jinhua, Zhejiang, 321004, China
| | - Abigail G Moore
- Department of Environmental and Plant Biology, Ohio University, Athens, Ohio, 45701, USA
| | - Zhihua Hua
- Department of Environmental and Plant Biology, Ohio University, Athens, Ohio, 45701, USA
- Interdisciplinary Program in Molecular and Cellular Biology, Ohio University, Athens, Ohio, 45701, USA
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29
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Affiliation(s)
- Emily Breeze
- School of Life SciencesUniversity of WarwickCoventry, United Kingdom
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30
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Schwihla M, Korbei B. The Beginning of the End: Initial Steps in the Degradation of Plasma Membrane Proteins. FRONTIERS IN PLANT SCIENCE 2020; 11:680. [PMID: 32528512 PMCID: PMC7253699 DOI: 10.3389/fpls.2020.00680] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 04/30/2020] [Indexed: 05/05/2023]
Abstract
The plasma membrane (PM), as border between the inside and the outside of a cell, is densely packed with proteins involved in the sensing and transmission of internal and external stimuli, as well as transport processes and is therefore vital for plant development as well as quick and accurate responses to the environment. It is consequently not surprising that several regulatory pathways participate in the tight regulation of the spatiotemporal control of PM proteins. Ubiquitination of PM proteins plays a key role in directing their entry into the endo-lysosomal system, serving as a signal for triggering endocytosis and further sorting for degradation. Nevertheless, a uniting picture of the different roles of the respective types of ubiquitination in the consecutive steps of down-regulation of membrane proteins is still missing. The trans-Golgi network (TGN), which acts as an early endosome (EE) in plants receives the endocytosed cargo, and here the decision is made to either recycled back to the PM or further delivered to the vacuole for degradation. A multi-complex machinery, the endosomal sorting complex required for transport (ESCRT), concentrates ubiquitinated proteins and ushers them into the intraluminal vesicles of multi-vesicular bodies (MVBs). Several ESCRTs have ubiquitin binding subunits, which anchor and guide the cargos through the endocytic degradation route. Basic enzymes and the mode of action in the early degradation steps of PM proteins are conserved in eukaryotes, yet many plant unique components exist, which are often essential in this pathway. Thus, deciphering the initial steps in the degradation of ubiquitinated PM proteins, which is the major focus of this review, will greatly contribute to the larger question of how plants mange to fine-tune their responses to their environment.
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