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Thiriet-Rupert S, Gain G, Jadoul A, Vigneron A, Bosman B, Carnol M, Motte P, Cardol P, Nouet C, Hanikenne M. Long-term acclimation to cadmium exposure reveals extensive phenotypic plasticity in Chlamydomonas. Plant Physiol 2021; 187:1653-1678. [PMID: 34618070 PMCID: PMC8566208 DOI: 10.1093/plphys/kiab375] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 07/17/2021] [Indexed: 05/06/2023]
Abstract
Increasing industrial and anthropogenic activities are producing and releasing more and more pollutants in the environment. Among them, toxic metals are one of the major threats for human health and natural ecosystems. Because photosynthetic organisms play a critical role in primary productivity and pollution management, investigating their response to metal toxicity is of major interest. Here, the green microalga Chlamydomonas (Chlamydomonas reinhardtii) was subjected to short (3 d) or chronic (6 months) exposure to 50 µM cadmium (Cd), and the recovery from chronic exposure was also examined. An extensive phenotypic characterization and transcriptomic analysis showed that the impact of Cd on biomass production of short-term (ST) exposed cells was almost entirely abolished by long-term (LT) acclimation. The underlying mechanisms were initiated at ST and further amplified after LT exposure resulting in a reversible equilibrium allowing biomass production similar to control condition. This included modification of cell wall-related gene expression and biofilm-like structure formation, dynamics of metal ion uptake and homeostasis, photosynthesis efficiency recovery and Cd acclimation through metal homeostasis adjustment. The contribution of the identified coordination of phosphorus and iron homeostasis (partly) mediated by the main phosphorus homeostasis regulator, Phosphate Starvation Response 1, and a basic Helix-Loop-Helix transcription factor (Cre05.g241636) was further investigated. The study reveals the highly dynamic physiological plasticity enabling algal cell growth in an extreme environment.
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Affiliation(s)
- Stanislas Thiriet-Rupert
- InBioS-PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, 4000 Liège, Belgium
- Present address: Unité de Génétique des Biofilms, Département Microbiologie, Institut Pasteur, Paris, France
| | - Gwenaëlle Gain
- InBioS-PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, 4000 Liège, Belgium
- InBioS-PhytoSystems, Genetics and Physiology of Microalgae, University of Liège, 4000 Liège, Belgium
| | - Alice Jadoul
- InBioS-PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, 4000 Liège, Belgium
| | - Amandine Vigneron
- InBioS-PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, 4000 Liège, Belgium
| | - Bernard Bosman
- InBioS-PhytoSystems, Laboratory of Plant and Microbial Ecology, University of Liège, 4000 Liège, Belgium
| | - Monique Carnol
- InBioS-PhytoSystems, Laboratory of Plant and Microbial Ecology, University of Liège, 4000 Liège, Belgium
| | - Patrick Motte
- InBioS-PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, 4000 Liège, Belgium
| | - Pierre Cardol
- InBioS-PhytoSystems, Genetics and Physiology of Microalgae, University of Liège, 4000 Liège, Belgium
| | - Cécile Nouet
- InBioS-PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, 4000 Liège, Belgium
| | - Marc Hanikenne
- InBioS-PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, 4000 Liège, Belgium
- Author for communication:
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Lekeux G, Crowet JM, Nouet C, Joris M, Jadoul A, Bosman B, Carnol M, Motte P, Lins L, Galleni M, Hanikenne M. Homology modeling and in vivo functional characterization of the zinc permeation pathway in a heavy metal P-type ATPase. J Exp Bot 2019; 70:329-341. [PMID: 30418580 PMCID: PMC6305203 DOI: 10.1093/jxb/ery353] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 10/01/2018] [Indexed: 05/26/2023]
Abstract
The P1B ATPase heavy metal ATPase 4 (HMA4) is responsible for zinc and cadmium translocation from roots to shoots in Arabidopsis thaliana. It couples ATP hydrolysis to cytosolic domain movements, enabling metal transport across the membrane. The detailed mechanism of metal permeation by HMA4 through the membrane remains elusive. Here, homology modeling of the HMA4 transmembrane region was conducted based on the crystal structure of a ZntA bacterial homolog. The analysis highlighted amino acids forming a metal permeation pathway, whose importance was subsequently investigated functionally through mutagenesis and complementation experiments in plants. Although the zinc pathway displayed overall conservation among the two proteins, significant differences were observed, especially in the entrance area with altered electronegativity and the presence of a ionic interaction/hydrogen bond network. The analysis also newly identified amino acids whose mutation results in total or partial loss of the protein function. In addition, comparison of zinc and cadmium accumulation in shoots of A. thaliana complemented lines revealed a number of HMA4 mutants exhibiting different abilities in zinc and cadmium translocation. These observations could be instrumental to design low cadmium-accumulating crops, hence decreasing human cadmium exposure.
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Affiliation(s)
- Gilles Lekeux
- InBioS - Center for Protein Engineering (CIP), Biological Macromolecules, University of Liège, Liège, Belgium
- InBioS - PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, Liège, Belgium
| | - Jean-Marc Crowet
- Laboratory of Molecular Biophysics at Interfaces, Gembloux Agro-Bio Tech, University of Liège, Gembloux, Belgium
| | - Cécile Nouet
- InBioS - PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, Liège, Belgium
| | - Marine Joris
- InBioS - PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, Liège, Belgium
| | - Alice Jadoul
- InBioS - PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, Liège, Belgium
| | - Bernard Bosman
- InBioS - PhytoSystems, Laboratory of Plant and Microbial Ecology, Department of Biology, Ecology, Evolution, University of Liège, Liège, Belgium
| | - Monique Carnol
- InBioS - PhytoSystems, Laboratory of Plant and Microbial Ecology, Department of Biology, Ecology, Evolution, University of Liège, Liège, Belgium
| | - Patrick Motte
- InBioS - PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, Liège, Belgium
| | - Laurence Lins
- Laboratory of Molecular Biophysics at Interfaces, Gembloux Agro-Bio Tech, University of Liège, Gembloux, Belgium
| | - Moreno Galleni
- InBioS - Center for Protein Engineering (CIP), Biological Macromolecules, University of Liège, Liège, Belgium
| | - Marc Hanikenne
- InBioS - PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, Liège, Belgium
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Schvartzman MS, Corso M, Fataftah N, Scheepers M, Nouet C, Bosman B, Carnol M, Motte P, Verbruggen N, Hanikenne M. Adaptation to high zinc depends on distinct mechanisms in metallicolous populations of Arabidopsis halleri. New Phytol 2018; 218:269-282. [PMID: 29292833 DOI: 10.1111/nph.14949] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 11/14/2017] [Indexed: 05/06/2023]
Abstract
Zinc (Zn) hyperaccumulation and hypertolerance are highly variable traits in Arabidopsis halleri. Metallicolous populations have evolved from nearby nonmetallicolous populations in multiple independent adaptation events. To determine whether these events resulted in similar or divergent adaptive strategies to high soil Zn concentrations, we compared two A. halleri metallicolous populations from distant genetic units in Europe (Poland (PL22) and Italy (I16)). The ionomic (Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES)) and transcriptomic (RNA sequencing (RNA-Seq)) responses to growth at 5 and 150 μM Zn were analyzed in root and shoot tissues to examine the contribution of the geographic origin and treatment to variation among populations. These analyses were enabled by the generation of a reference A. halleri transcriptome assembly. The genetic unit accounted for the largest variation in the gene expression profile, whereas the two populations had contrasting Zn accumulation phenotypes and shared little common response to the Zn treatment. The PL22 population displayed an iron deficiency response at high Zn in roots and shoots, which may account for higher Zn accumulation. By contrast, I16, originating from a highly Zn-contaminated soil, strongly responded to control conditions. Our data suggest that distinct mechanisms support adaptation to high Zn in soils among A. halleri metallicolous populations.
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Affiliation(s)
- M Sol Schvartzman
- InBioS-PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, Liège, B-4000, Belgium
| | - Massimiliano Corso
- Physiology and Plant Molecular Genetics, Free University of Brussels, Brussels, 1050, Belgium
| | - Nazeer Fataftah
- InBioS-PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, Liège, B-4000, Belgium
| | - Maxime Scheepers
- InBioS-PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, Liège, B-4000, Belgium
| | - Cécile Nouet
- InBioS-PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, Liège, B-4000, Belgium
| | - Bernard Bosman
- Laboratory of Plant and Microbial Ecology, Department of Biology, Ecology and Evolution, University of Liège, Liège, B-4000, Belgium
| | - Monique Carnol
- Laboratory of Plant and Microbial Ecology, Department of Biology, Ecology and Evolution, University of Liège, Liège, B-4000, Belgium
| | - Patrick Motte
- InBioS-PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, Liège, B-4000, Belgium
| | - Nathalie Verbruggen
- Physiology and Plant Molecular Genetics, Free University of Brussels, Brussels, 1050, Belgium
| | - Marc Hanikenne
- InBioS-PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, Liège, B-4000, Belgium
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Nouet C, Charlier JB, Carnol M, Bosman B, Farnir F, Motte P, Hanikenne M. Functional analysis of the three HMA4 copies of the metal hyperaccumulator Arabidopsis halleri. J Exp Bot 2015; 66:5783-95. [PMID: 26044091 PMCID: PMC4566976 DOI: 10.1093/jxb/erv280] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
In Arabidopsis halleri, the HMA4 gene has an essential function in Zn/Cd hypertolerance and hyperaccumulation by mediating root-to-shoot translocation of metals. Constitutive high expression of AhHMA4 results from a tandem triplication and cis-activation of the promoter of all three copies. The three AhHMA4 copies possess divergent promoter sequences, but highly conserved coding sequences, and display identical expression profiles in the root and shoot vascular system. Here, an AhHMA4::GFP fusion was expressed under the control of each of the three A. halleri HMA4 promoters in a hma2hma4 double mutant of A. thaliana to individually examine the function of each AhHMA4 copy. The protein showed non-polar localization at the plasma membrane of the root pericycle cells of both A. thaliana and A. halleri. The expression of each AhHMA4::GFP copy complemented the severe Zn-deficiency phenotype of the hma2hma4 mutant by restoring root-to-shoot translocation of Zn. However, each copy had a different impact on metal homeostasis in the A. thaliana genetic background: AhHMA4 copies 2 and 3 were more highly expressed and provided higher Zn tolerance in roots and accumulation in shoots than copy 1, and AhHMA4 copy 3 also increased Cd tolerance in roots. These data suggest a certain extent of functional differentiation among the three A. halleri HMA4 copies, stemming from differences in expression levels rather than in expression profile. HMA4 is a key node of the Zn homeostasis network and small changes in expression level can have a major impact on Zn allocation to root or shoot tissues.
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Affiliation(s)
- Cécile Nouet
- Functional Genomics and Plant Molecular Imaging, Center for Protein Engineering (CIP), Department of Life Sciences, University of Liège, B-4000 Liège, Belgium
| | - Jean-Benoit Charlier
- Functional Genomics and Plant Molecular Imaging, Center for Protein Engineering (CIP), Department of Life Sciences, University of Liège, B-4000 Liège, Belgium
| | - Monique Carnol
- Laboratory of Plant and Microbial Ecology, Department of Biology, Ecology, Evolution, University of Liège, B-4000 Liège, Belgium
| | - Bernard Bosman
- Laboratory of Plant and Microbial Ecology, Department of Biology, Ecology, Evolution, University of Liège, B-4000 Liège, Belgium
| | - Frédéric Farnir
- Biostatistics and Bioinformatics, FARAH, Faculty of Veterinary Medicine, University of Liège, B-4000 Liège, Belgium
| | - Patrick Motte
- Functional Genomics and Plant Molecular Imaging, Center for Protein Engineering (CIP), Department of Life Sciences, University of Liège, B-4000 Liège, Belgium PhytoSYSTEMS, University of Liège, B-4000 Liège, Belgium
| | - Marc Hanikenne
- Functional Genomics and Plant Molecular Imaging, Center for Protein Engineering (CIP), Department of Life Sciences, University of Liège, B-4000 Liège, Belgium PhytoSYSTEMS, University of Liège, B-4000 Liège, Belgium
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Charlier JB, Polese C, Nouet C, Carnol M, Bosman B, Krämer U, Motte P, Hanikenne M. Zinc triggers a complex transcriptional and post-transcriptional regulation of the metal homeostasis gene FRD3 in Arabidopsis relatives. J Exp Bot 2015; 66:3865-78. [PMID: 25900619 PMCID: PMC4473987 DOI: 10.1093/jxb/erv188] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
In Arabidopsis thaliana, FRD3 (FERRIC CHELATE REDUCTASE DEFECTIVE 3) plays a central role in metal homeostasis. FRD3 is among a set of metal homeostasis genes that are constitutively highly expressed in roots and shoots of Arabidopsis halleri, a zinc hyperaccumulating and hypertolerant species. Here, we examined the regulation of FRD3 by zinc in both species to shed light on the evolutionary processes underlying the evolution of hyperaccumulation in A. halleri. We combined gene expression studies with the use of β-glucuronidase and green fluorescent protein reporter constructs to compare the expression profile and transcriptional and post-transcriptional regulation of FRD3 in both species. The AtFRD3 and AhFRD3 genes displayed a conserved expression profile. In A. thaliana, alternative transcription initiation sites from two promoters determined transcript variants that were differentially regulated by zinc supply in roots and shoots to favour the most highly translated variant under zinc-excess conditions. In A. halleri, a single transcript variant with higher transcript stability and enhanced translation has been maintained. The FRD3 gene thus undergoes complex transcriptional and post-transcriptional regulation in Arabidopsis relatives. Our study reveals that a diverse set of mechanisms underlie increased gene dosage in the A. halleri lineage and illustrates how an environmental challenge can alter gene regulation.
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Affiliation(s)
- Jean-Benoit Charlier
- Functional Genomics and Plant Molecular Imaging, Center for Protein Engineering (CIP), Department of Life Sciences, University of Liège, B-4000 Liège, Belgium
| | - Catherine Polese
- Functional Genomics and Plant Molecular Imaging, Center for Protein Engineering (CIP), Department of Life Sciences, University of Liège, B-4000 Liège, Belgium
| | - Cécile Nouet
- Functional Genomics and Plant Molecular Imaging, Center for Protein Engineering (CIP), Department of Life Sciences, University of Liège, B-4000 Liège, Belgium
| | - Monique Carnol
- Laboratory of Plant and Microbial Ecology, Department of Biology, Ecology, Evolution, University of Liège, B-4000 Liège, Belgium
| | - Bernard Bosman
- Laboratory of Plant and Microbial Ecology, Department of Biology, Ecology, Evolution, University of Liège, B-4000 Liège, Belgium
| | - Ute Krämer
- Department of Plant Physiology, Ruhr University Bochum, D-44801 Bochum, Germany
| | - Patrick Motte
- Functional Genomics and Plant Molecular Imaging, Center for Protein Engineering (CIP), Department of Life Sciences, University of Liège, B-4000 Liège, Belgium PhytoSYSTEMS, University of Liège, B-4000 Liège, Belgium
| | - Marc Hanikenne
- Functional Genomics and Plant Molecular Imaging, Center for Protein Engineering (CIP), Department of Life Sciences, University of Liège, B-4000 Liège, Belgium PhytoSYSTEMS, University of Liège, B-4000 Liège, Belgium
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Ostojić J, Panozzo C, Lasserre JP, Nouet C, Courtin F, Blancard C, di Rago JP, Dujardin G. The energetic state of mitochondria modulates complex III biogenesis through the ATP-dependent activity of Bcs1. Cell Metab 2013; 18:567-77. [PMID: 24055101 DOI: 10.1016/j.cmet.2013.08.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Revised: 03/27/2013] [Accepted: 08/12/2013] [Indexed: 01/08/2023]
Abstract
Our understanding of the mechanisms involved in mitochondrial biogenesis has continuously expanded during the last decades, yet little is known about how they are modulated to optimize the functioning of mitochondria. Here, we show that mutations in the ATP binding domain of Bcs1, a chaperone involved in the assembly of complex III, can be rescued by mutations that decrease the ATP hydrolytic activity of the ATP synthase. Our results reveal a Bcs1-mediated control loop in which the biogenesis of complex III is modulated by the energy-transducing activity of mitochondria. Although ATP is well known as a regulator of a number of cellular activities, we show here that ATP can be also used to modulate the biogenesis of an enzyme by controlling a specific chaperone involved in its assembly. Our study further highlights the intramitochondrial adenine nucleotide pool as a potential target for the treatment of Bcs1-based disorders.
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Affiliation(s)
- Jelena Ostojić
- Centre de Génétique Moléculaire, Université Paris-Sud, avenue de la Terrasse, 91198 Gif sur Yvette, France
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Nouet C, Motte P, Hanikenne M. Chloroplastic and mitochondrial metal homeostasis. Trends Plant Sci 2011; 16:395-404. [PMID: 21489854 DOI: 10.1016/j.tplants.2011.03.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Revised: 02/25/2011] [Accepted: 03/07/2011] [Indexed: 05/03/2023]
Abstract
Transition metal deficiency has a strong impact on the growth and survival of an organism. Indeed, transition metals, such as iron, copper, manganese and zinc, constitute essential cofactors for many key cellular functions. Both photosynthesis and respiration rely on metal cofactor-mediated electron transport chains. Chloroplasts and mitochondria are, therefore, organelles with high metal ion demand and represent essential components of the metal homeostasis network in photosynthetic cells. In this review, we describe the metal requirements of chloroplasts and mitochondria, the acclimation of their functions to metal deficiency and recent advances in our understanding of their contributions to cellular metal homeostasis, the control of the cellular redox status and the synthesis of metal cofactors.
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Affiliation(s)
- Cécile Nouet
- Functional Genomics and Plant Molecular Imaging, Center for Protein Engineering, Department of Life Sciences (B22), University of Liège, Belgium
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Hanikenne M, Nouet C. Metal hyperaccumulation and hypertolerance: a model for plant evolutionary genomics. Curr Opin Plant Biol 2011; 14:252-9. [PMID: 21531166 DOI: 10.1016/j.pbi.2011.04.003] [Citation(s) in RCA: 108] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Revised: 04/04/2011] [Accepted: 04/07/2011] [Indexed: 05/21/2023]
Abstract
In the course of evolution, plants adapted to widely differing metal availabilities in soils and therefore represent an important source of natural variation of metal homeostasis networks. Research on plant metal homeostasis can thus provide insights into the functioning, regulation and adaptation of biological networks. Here, we describe major recent breakthroughs in the understanding of the genetic and molecular basis of metal hyperaccumulation and associated hypertolerance, a naturally selected complex trait which represents an extreme adaptation of the metal homeostasis network. Investigations in this field reveal further the molecular alterations underlying the evolution of natural phenotypic diversity and provide a highly relevant framework for comparative genomics.
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Affiliation(s)
- Marc Hanikenne
- Functional Genomics and Plant Molecular Imaging, Center for Protein Engineering, Department of Life Sciences (B22), University of Liège, Liège, Belgium.
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Nouet C, Truan G, Mathieu L, Dujardin G. Functional Analysis of Yeast bcs1 Mutants Highlights the Role of Bcs1p-Specific Amino Acids in the AAA Domain. J Mol Biol 2009; 388:252-61. [DOI: 10.1016/j.jmb.2009.03.018] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2008] [Revised: 03/04/2009] [Accepted: 03/09/2009] [Indexed: 11/28/2022]
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Nouet C, Bourens M, Hlavacek O, Marsy S, Lemaire C, Dujardin G. Rmd9p controls the processing/stability of mitochondrial mRNAs and its overexpression compensates for a partial deficiency of oxa1p in Saccharomyces cerevisiae. Genetics 2006; 175:1105-15. [PMID: 17194787 PMCID: PMC1840076 DOI: 10.1534/genetics.106.063883] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Oxa1p is a key component of the general membrane insertion machinery of eukaryotic respiratory complex subunits encoded by the mitochondrial genome. In this study, we have generated a respiratory-deficient mutant, oxa1-E65G-F229S, that contains two substitutions in the predicted intermembrane space domain of Oxa1p. The respiratory deficiency due to this mutation is compensated for by overexpressing RMD9. We show that Rmd9p is an extrinsic membrane protein facing the matrix side of the mitochondrial inner membrane. Its deletion leads to a pleiotropic effect on respiratory complex biogenesis. The steady-state level of all the mitochondrial mRNAs encoding respiratory complex subunits is strongly reduced in the Deltarmd9 mutant, and there is a slight decrease in the accumulation of two RNAs encoding components of the small subunit of the mitochondrial ribosome. Overexpressing RMD9 leads to an increase in the steady-state level of mitochondrial RNAs, and we discuss how this increase could suppress the oxa1 mutations and compensate for the membrane insertion defect of the subunits encoded by these mRNAs.
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Affiliation(s)
- Cécile Nouet
- Centre de Génétique Moléculaire, 91198 Gif-sur-Yvette, France
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