1
|
Song C, Li Y, Yang M, Li T, Hou Y, Liu Y, Xu C, Liu J, Millar AH, Wang N, Li L. Protein aggregation in plant mitochondria lacking Lon1 inhibits translation and induces unfolded protein responses. PLANT, CELL & ENVIRONMENT 2024. [PMID: 38988259 DOI: 10.1111/pce.15035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 06/20/2024] [Accepted: 06/27/2024] [Indexed: 07/12/2024]
Abstract
Loss of Lon1 led to stunted plant growth and accumulation of nuclear-encoded mitochondrial proteins including Lon1 substrates. However, an in-depth label-free proteomics quantification of mitochondrial proteins in lon1 revealed that the majority of mitochondrial-encoded proteins decreased in abundance. Additionally, we found that lon1 mutants contained protein aggregates in the mitochondrial that were enriched in metabolic enzymes, ribosomal subunits and PPR-containing proteins of the translation apparatus. These mutants exhibited reduced general mitochondrial translation as well as deficiencies in RNA splicing and editing. These findings support the role of Lon1 in maintaining a functional translational apparatus for mitochondrial-encoded gene translation. Transcriptome analysis of lon1 revealed a mitochondrial unfolded protein response reminiscent of the mitochondrial retrograde signalling dependent on the transcription factor ANAC017. Notably, lon1 mutants exhibited transiently elevated ethylene production, and the shortened hypocotyl observed in lon1 mutants during skotomorphogenesis was partially alleviated by ethylene inhibitors. Furthermore, the short root phenotype was partially ameliorated by introducing a mutation in the ethylene receptor ETR1. Interestingly, the upregulation of only a select few target genes was linked to ETR1-mediated ethylene signalling. Together this provides multiple steps in the link between loss of Lon1 and signalling responses to restore mitochondrial protein homoeostasis in plants.
Collapse
Affiliation(s)
- Ce Song
- Frontiers Science Center for Cell Responses, Department of Plant Biology and Ecology, College of Life Sciences, Nankai University, Tianjin, China
| | - Yuanyuan Li
- Frontiers Science Center for Cell Responses, Department of Plant Biology and Ecology, College of Life Sciences, Nankai University, Tianjin, China
| | - Mengmeng Yang
- Frontiers Science Center for Cell Responses, Department of Plant Biology and Ecology, College of Life Sciences, Nankai University, Tianjin, China
| | - Tiantian Li
- Frontiers Science Center for Cell Responses, Department of Plant Biology and Ecology, College of Life Sciences, Nankai University, Tianjin, China
| | - Yuqi Hou
- Frontiers Science Center for Cell Responses, Department of Plant Biology and Ecology, College of Life Sciences, Nankai University, Tianjin, China
| | - Yinyin Liu
- Frontiers Science Center for Cell Responses, Department of Plant Biology and Ecology, College of Life Sciences, Nankai University, Tianjin, China
| | - Chang Xu
- Frontiers Science Center for Cell Responses, Department of Plant Biology and Ecology, College of Life Sciences, Nankai University, Tianjin, China
| | - Jinjian Liu
- Key Laboratory of Radiopharmacokinetics for Innovative Drugs, Chinese Academy of Medical Sciences, and Institute of Radiation Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China
| | - A Harvey Millar
- ARC Centre of Excellence in Plant Energy Biology, School of Molecular Science, The University of Western Australia, Crawley, Western Australia, Australia
| | - Ningning Wang
- Frontiers Science Center for Cell Responses, Department of Plant Biology and Ecology, College of Life Sciences, Nankai University, Tianjin, China
| | - Lei Li
- Frontiers Science Center for Cell Responses, Department of Plant Biology and Ecology, College of Life Sciences, Nankai University, Tianjin, China
| |
Collapse
|
2
|
Tran HC, Schmitt V, Lama S, Wang C, Launay-Avon A, Bernfur K, Sultan K, Khan K, Brunaud V, Liehrmann A, Castandet B, Levander F, Rasmusson AG, Mireau H, Delannoy E, Van Aken O. An mTRAN-mRNA interaction mediates mitochondrial translation initiation in plants. Science 2023; 381:eadg0995. [PMID: 37651534 DOI: 10.1126/science.adg0995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 08/02/2023] [Indexed: 09/02/2023]
Abstract
Plant mitochondria represent the largest group of respiring organelles on the planet. Plant mitochondrial messenger RNAs (mRNAs) lack Shine-Dalgarno-like ribosome-binding sites, so it is unknown how plant mitoribosomes recognize mRNA. We show that "mitochondrial translation factors" mTRAN1 and mTRAN2 are land plant-specific proteins, required for normal mitochondrial respiration chain biogenesis. Our studies suggest that mTRANs are noncanonical pentatricopeptide repeat (PPR)-like RNA binding proteins of the mitoribosomal "small" subunit. We identified conserved Adenosine (A)/Uridine (U)-rich motifs in the 5' regions of plant mitochondrial mRNAs. mTRAN1 binds this motif, suggesting that it is a mitoribosome homing factor to identify mRNAs. We demonstrate that mTRANs are likely required for translation of all plant mitochondrial mRNAs. Plant mitochondrial translation initiation thus appears to use a protein-mRNA interaction that is divergent from bacteria or mammalian mitochondria.
Collapse
Affiliation(s)
| | | | - Sbatie Lama
- Department of Biology, Lund University, Lund, Sweden
| | - Chuande Wang
- Université Paris-Saclay, INRAE, AgroParisTech, Institut Jean-Pierre Bourgin (IJPB), 78000 Versailles, France
| | - Alexandra Launay-Avon
- Université Paris-Saclay, CNRS, INRAE, Université d'Évry, Institute of Plant Sciences Paris-Saclay (IPS2), 91405 Orsay, France
- Université Paris Cité, CNRS, INRAE, Institute of Plant Sciences Paris-Saclay (IPS2), 91405, Orsay, France
| | - Katja Bernfur
- Department of Chemistry, Lund University, Lund, Sweden
| | - Kristin Sultan
- Department of Immunotechnology, Lund University, Lund, Sweden
| | - Kasim Khan
- Department of Biology, Lund University, Lund, Sweden
| | - Véronique Brunaud
- Université Paris-Saclay, CNRS, INRAE, Université d'Évry, Institute of Plant Sciences Paris-Saclay (IPS2), 91405 Orsay, France
- Université Paris Cité, CNRS, INRAE, Institute of Plant Sciences Paris-Saclay (IPS2), 91405, Orsay, France
| | - Arnaud Liehrmann
- Université Paris-Saclay, CNRS, INRAE, Université d'Évry, Institute of Plant Sciences Paris-Saclay (IPS2), 91405 Orsay, France
- Université Paris Cité, CNRS, INRAE, Institute of Plant Sciences Paris-Saclay (IPS2), 91405, Orsay, France
- Université Paris-Saclay, CNRS, Université d'Évry, Laboratoire de Mathématiques et Modélisation d'Évry, 91037 Évry-Courcouronnes, France
| | - Benoît Castandet
- Université Paris-Saclay, CNRS, INRAE, Université d'Évry, Institute of Plant Sciences Paris-Saclay (IPS2), 91405 Orsay, France
- Université Paris Cité, CNRS, INRAE, Institute of Plant Sciences Paris-Saclay (IPS2), 91405, Orsay, France
| | - Fredrik Levander
- Department of Immunotechnology, Lund University, Lund, Sweden
- National Bioinformatics Infrastructure Sweden, Science for Life Laboratory, Lund University, Lund, Sweden
| | | | - Hakim Mireau
- Université Paris-Saclay, INRAE, AgroParisTech, Institut Jean-Pierre Bourgin (IJPB), 78000 Versailles, France
| | - Etienne Delannoy
- Université Paris-Saclay, CNRS, INRAE, Université d'Évry, Institute of Plant Sciences Paris-Saclay (IPS2), 91405 Orsay, France
- Université Paris Cité, CNRS, INRAE, Institute of Plant Sciences Paris-Saclay (IPS2), 91405, Orsay, France
| | | |
Collapse
|