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Yao L, Jia Y, Zhang Q, Zheng X, Yang H, Dai J, Chen X. Adaptive laboratory evolution to obtain furfural tolerant Saccharomyces cerevisiae for bioethanol production and the underlying mechanism. Front Microbiol 2024; 14:1333777. [PMID: 38239732 PMCID: PMC10794740 DOI: 10.3389/fmicb.2023.1333777] [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: 11/06/2023] [Accepted: 12/05/2023] [Indexed: 01/22/2024] Open
Abstract
Introduction Furfural, a main inhibitor produced during pretreatment of lignocellulose, has shown inhibitory effects on S. cerevisiae. Method In the present study, new strains named 12-1 with enhanced resistance to furfural were obtained through adaptive laboratory evolution, which exhibited a shortened lag phase by 36 h, and an increased ethanol conversion rate by 6.67% under 4 g/L furfural. Results and Discussion To further explore the mechanism of enhanced furfural tolerance, ADR1_1802 mutant was constructed by CRISPR/Cas9 technology, based on whole genome re-sequencing data. The results indicated that the time when ADR1_1802 begin to grow was shortened by 20 h compared with reference strain (S. cerevisiae CEN.PK113-5D) when furfural was 4 g/L. Additionally, the transcription levels of GRE2 and ADH6 in ADR1_ 1802 mutant were increased by 53.69 and 44.95%, respectively, according to real-time fluorescence quantitative PCR analysis. These findings suggest that the enhanced furfural tolerance of mutant is due to accelerated furfural degradation. Importance: Renewable carbon worldwide is vital to achieve "zero carbon" target. Bioethanol obtained from biomass is one of them. To make bioethanol price competitive to fossil fuel, higher ethanol yield is necessary, therefore, monosaccharide produced during biomass pretreatment should be effectively converted to ethanol by Saccharomyces cerevisiae. However, inhibitors formed by glucose or xylose oxidation could make ethanol yield lower. Thus, inhibitor tolerant Saccharomyces cerevisiae is important to this process. As one of the main component of pretreatment hydrolysate, furfural shows obvious impact on growth and ethanol production of Saccharomyces cerevisiae. To get furfural tolerant Saccharomyces cerevisiae and find the underlying mechanism, adaptive laboratory evolution and CRISPR/Cas9 technology were applied in the present study.
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Affiliation(s)
- Lan Yao
- Key Laboratory of Fermentation Engineering (Ministry of Education), Cooperative Innovation Center of Industrial Fermentation (Ministry of Education and Hubei Province), College of Bioengineering, Hubei University of Technology, Wuhan, China
| | - Youpiao Jia
- Key Laboratory of Fermentation Engineering (Ministry of Education), Cooperative Innovation Center of Industrial Fermentation (Ministry of Education and Hubei Province), College of Bioengineering, Hubei University of Technology, Wuhan, China
| | - Qingyan Zhang
- Key Laboratory of Fermentation Engineering (Ministry of Education), Cooperative Innovation Center of Industrial Fermentation (Ministry of Education and Hubei Province), College of Bioengineering, Hubei University of Technology, Wuhan, China
| | - Xueyun Zheng
- Key Laboratory of Fermentation Engineering (Ministry of Education), Cooperative Innovation Center of Industrial Fermentation (Ministry of Education and Hubei Province), College of Bioengineering, Hubei University of Technology, Wuhan, China
| | - Haitao Yang
- Hubei Provincial Key Laboratory of Green Materials for Light Industry, Hubei University of Technology, Wuhan, China
| | - Jun Dai
- Key Laboratory of Fermentation Engineering (Ministry of Education), Cooperative Innovation Center of Industrial Fermentation (Ministry of Education and Hubei Province), College of Bioengineering, Hubei University of Technology, Wuhan, China
| | - Xiong Chen
- Key Laboratory of Fermentation Engineering (Ministry of Education), Cooperative Innovation Center of Industrial Fermentation (Ministry of Education and Hubei Province), College of Bioengineering, Hubei University of Technology, Wuhan, China
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Alves R, Pazos-Gil M, Medina-Carbonero M, Sanz-Alcázar A, Delaspre F, Tamarit J. Evolution of an Iron-Detoxifying Protein: Eukaryotic and Rickettsia Frataxins Contain a Conserved Site Which Is Not Present in Their Bacterial Homologues. Int J Mol Sci 2022; 23:13151. [PMID: 36361939 PMCID: PMC9658677 DOI: 10.3390/ijms232113151] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 10/21/2022] [Accepted: 10/27/2022] [Indexed: 01/07/2024] Open
Abstract
Friedreich's ataxia is a neurodegenerative disease caused by mutations in the frataxin gene. Frataxin homologues, including bacterial CyaY proteins, can be found in most species and play a fundamental role in mitochondrial iron homeostasis, either promoting iron assembly into metaloproteins or contributing to iron detoxification. While several lines of evidence suggest that eukaryotic frataxins are more effective than bacterial ones in iron detoxification, the residues involved in this gain of function are unknown. In this work, we analyze conservation of amino acid sequence and protein structure among frataxins and CyaY proteins to identify four highly conserved residue clusters and group them into potential functional clusters. Clusters 1, 2, and 4 are present in eukaryotic frataxins and bacterial CyaY proteins. Cluster 3, containing two serines, a tyrosine, and a glutamate, is only present in eukaryotic frataxins and on CyaY proteins from the Rickettsia genus. Residues from cluster 3 are blocking a small cavity of about 40 Å present in E. coli's CyaY. The function of this cluster is unknown, but we hypothesize that its tyrosine may contribute to prevent formation of reactive oxygen species during iron detoxification. This cluster provides an example of gain of function during evolution in a protein involved in iron homeostasis, as our results suggests that Cluster 3 was present in the endosymbiont ancestor of mitochondria and was conserved in eukaryotic frataxins.
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Affiliation(s)
| | | | | | | | | | - Jordi Tamarit
- Departament de Ciències Mèdiques Bàsiques, Facultat de Medicina, IRBLleida, Universitat de Lleida, 25001 Lleida, Spain
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3
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Medina-Carbonero M, Sanz-Alcázar A, Britti E, Delaspre F, Cabiscol E, Ros J, Tamarit J. Mice harboring the FXN I151F pathological point mutation present decreased frataxin levels, a Friedreich ataxia-like phenotype, and mitochondrial alterations. Cell Mol Life Sci 2022; 79:74. [PMID: 35038030 PMCID: PMC8763788 DOI: 10.1007/s00018-021-04100-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 11/21/2021] [Accepted: 12/16/2021] [Indexed: 12/13/2022]
Abstract
Friedreich Ataxia (FA) is a rare neuro-cardiodegenerative disease caused by mutations in the frataxin (FXN) gene. The most prevalent mutation is a GAA expansion in the first intron of the gene causing decreased frataxin expression. Some patients present the GAA expansion in one allele and a missense mutation in the other allele. One of these mutations, FXNI154F, was reported to result in decreased content of mature frataxin and increased presence of an insoluble intermediate proteoform in cellular models. By introducing this mutation into the murine Fxn gene (I151F, equivalent to human I154F) we have now analyzed the consequences of this pathological point mutation in vivo. We have observed that FXNI151F homozygous mice present low frataxin levels in all tissues, with no evidence of insoluble proteoforms. Moreover, they display neurological deficits resembling those observed in FA patients. Biochemical analysis of heart, cerebrum and cerebellum have revealed decreased content of components from OXPHOS complexes I and II, decreased aconitase activity, and alterations in antioxidant defenses. These mitochondrial alterations are more marked in the nervous system than in heart, precede the appearance of neurological symptoms, and are similar to those observed in other FA models. We conclude that the primary pathological mechanism underlying the I151F mutation is frataxin deficiency, like in patients carrying GAA expansions. Therefore, patients carrying the I154F mutation would benefit from frataxin replacement therapies. Furthermore, our results also show that the FXNI151F mouse is an excellent tool for analyzing tissue-specific consequences of frataxin deficiency and for testing new therapies.
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Affiliation(s)
- Marta Medina-Carbonero
- Dept. Ciències Mèdiques Bàsiques, Fac. Medicina, IRBLleida, Universitat de Lleida, Av. Rovira Roure, 80, 25198, Lleida, Spain
| | - Arabela Sanz-Alcázar
- Dept. Ciències Mèdiques Bàsiques, Fac. Medicina, IRBLleida, Universitat de Lleida, Av. Rovira Roure, 80, 25198, Lleida, Spain
| | - Elena Britti
- Dept. Ciències Mèdiques Bàsiques, Fac. Medicina, IRBLleida, Universitat de Lleida, Av. Rovira Roure, 80, 25198, Lleida, Spain
| | - Fabien Delaspre
- Dept. Ciències Mèdiques Bàsiques, Fac. Medicina, IRBLleida, Universitat de Lleida, Av. Rovira Roure, 80, 25198, Lleida, Spain
| | - Elisa Cabiscol
- Dept. Ciències Mèdiques Bàsiques, Fac. Medicina, IRBLleida, Universitat de Lleida, Av. Rovira Roure, 80, 25198, Lleida, Spain
| | - Joaquim Ros
- Dept. Ciències Mèdiques Bàsiques, Fac. Medicina, IRBLleida, Universitat de Lleida, Av. Rovira Roure, 80, 25198, Lleida, Spain
| | - Jordi Tamarit
- Dept. Ciències Mèdiques Bàsiques, Fac. Medicina, IRBLleida, Universitat de Lleida, Av. Rovira Roure, 80, 25198, Lleida, Spain.
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Tamarit J, Britti E, Delaspre F, Medina-Carbonero M, Sanz-Alcázar A, Cabiscol E, Ros J. Mitochondrial iron and calcium homeostasis in Friedreich ataxia. IUBMB Life 2021; 73:543-553. [PMID: 33675183 DOI: 10.1002/iub.2457] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 02/08/2021] [Accepted: 02/08/2021] [Indexed: 12/13/2022]
Abstract
Friedreich Ataxia is a neuro-cardiodegenerative disease caused by the deficiency of frataxin, a mitochondrial protein. Many evidences indicate that frataxin deficiency causes an unbalance of iron homeostasis. Nevertheless, in the last decade many results also highlighted the importance of calcium unbalance in the deleterious downstream effects caused by frataxin deficiency. In this review, the role of these two metals has been gathered to give a whole view of how iron and calcium dyshomeostasys impacts on cellular functions and, as a result, which strategies can be followed to find an effective therapy for the disease.
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Affiliation(s)
- Jordi Tamarit
- Dept. Ciències Mèdiques Bàsiques, Universitat de Lleida, IRBLleida, Lleida, Spain
| | - Elena Britti
- Dept. Ciències Mèdiques Bàsiques, Universitat de Lleida, IRBLleida, Lleida, Spain
| | - Fabien Delaspre
- Dept. Ciències Mèdiques Bàsiques, Universitat de Lleida, IRBLleida, Lleida, Spain
| | | | - Arabela Sanz-Alcázar
- Dept. Ciències Mèdiques Bàsiques, Universitat de Lleida, IRBLleida, Lleida, Spain
| | - Elisa Cabiscol
- Dept. Ciències Mèdiques Bàsiques, Universitat de Lleida, IRBLleida, Lleida, Spain
| | - Joaquim Ros
- Dept. Ciències Mèdiques Bàsiques, Universitat de Lleida, IRBLleida, Lleida, Spain
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5
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Purroy R, Medina-Carbonero M, Ros J, Tamarit J. Frataxin-deficient cardiomyocytes present an altered thiol-redox state which targets actin and pyruvate dehydrogenase. Redox Biol 2020; 32:101520. [PMID: 32279039 PMCID: PMC7152683 DOI: 10.1016/j.redox.2020.101520] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 03/10/2020] [Accepted: 03/21/2020] [Indexed: 01/11/2023] Open
Abstract
Friedreich ataxia (FA) is a cardioneurodegenerative disease caused by deficient frataxin expression. This mitochondrial protein has been related to iron homeostasis, energy metabolism, and oxidative stress. Previously, we set up a cardiac cellular model of FA based on neonatal rat cardiac myocytes (NRVM) and lentivirus-mediated frataxin RNA interference. These frataxin-deficient NRVMs presented lipid droplet accumulation, mitochondrial swelling and signs of oxidative stress. Therefore, we decided to explore the presence of protein thiol modifications in this model. With this purpose, reduced glutathione (GSH) levels were measured and the presence of glutathionylated proteins was analyzed. We observed decreased GSH content and increased presence of glutahionylated actin in frataxin-deficient NRVMs. Moreover, the presence of oxidized cysteine residues was investigated using the thiol-reactive fluorescent probe iodoacetamide-Bodipy and 2D-gel electrophoresis. With this approach, we identified two proteins with altered redox status in frataxin-deficient NRVMs: electron transfer flavoprotein-ubiquinone oxidoreductase and dihydrolipoyl dehydrogenase (DLDH). As DLDH is involved in protein-bound lipoic acid redox cycling, we analyzed the redox state of this cofactor and we observed that lipoic acid from pyruvate dehydrogenase was more oxidized in frataxin-deficient cells. Also, by targeted proteomics, we observed a decreased content on the PDH A1 subunit from pyruvate dehydrogenase. Finally, we analyzed the consequences of supplementing frataxin-deficient NRVMs with the PDH cofactors thiamine and lipoic acid, the PDH activator dichloroacetate and the antioxidants N-acetyl cysteine and Tiron. Both dichloroacetate and Tiron were able to partially prevent lipid droplet accumulation in these cells. Overall, these results indicate that frataxin-deficient NRVMs present an altered thiol-redox state which could contribute to the cardiac pathology.
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Affiliation(s)
- Rosa Purroy
- Dept. Ciències Mèdiques Bàsiques, Fac. Medicina, IRBLLeida, Universitat de Lleida, Lleida, Spain
| | - Marta Medina-Carbonero
- Dept. Ciències Mèdiques Bàsiques, Fac. Medicina, IRBLLeida, Universitat de Lleida, Lleida, Spain
| | - Joaquim Ros
- Dept. Ciències Mèdiques Bàsiques, Fac. Medicina, IRBLLeida, Universitat de Lleida, Lleida, Spain
| | - Jordi Tamarit
- Dept. Ciències Mèdiques Bàsiques, Fac. Medicina, IRBLLeida, Universitat de Lleida, Lleida, Spain.
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Myers KS, Riley NM, MacGilvray ME, Sato TK, McGee M, Heilberger J, Coon JJ, Gasch AP. Rewired cellular signaling coordinates sugar and hypoxic responses for anaerobic xylose fermentation in yeast. PLoS Genet 2019; 15:e1008037. [PMID: 30856163 PMCID: PMC6428351 DOI: 10.1371/journal.pgen.1008037] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 03/21/2019] [Accepted: 02/20/2019] [Indexed: 01/08/2023] Open
Abstract
Microbes can be metabolically engineered to produce biofuels and biochemicals, but rerouting metabolic flux toward products is a major hurdle without a systems-level understanding of how cellular flux is controlled. To understand flux rerouting, we investigated a panel of Saccharomyces cerevisiae strains with progressive improvements in anaerobic fermentation of xylose, a sugar abundant in sustainable plant biomass used for biofuel production. We combined comparative transcriptomics, proteomics, and phosphoproteomics with network analysis to understand the physiology of improved anaerobic xylose fermentation. Our results show that upstream regulatory changes produce a suite of physiological effects that collectively impact the phenotype. Evolved strains show an unusual co-activation of Protein Kinase A (PKA) and Snf1, thus combining responses seen during feast on glucose and famine on non-preferred sugars. Surprisingly, these regulatory changes were required to mount the hypoxic response when cells were grown on xylose, revealing a previously unknown connection between sugar source and anaerobic response. Network analysis identified several downstream transcription factors that play a significant, but on their own minor, role in anaerobic xylose fermentation, consistent with the combinatorial effects of small-impact changes. We also discovered that different routes of PKA activation produce distinct phenotypes: deletion of the RAS/PKA inhibitor IRA2 promotes xylose growth and metabolism, whereas deletion of PKA inhibitor BCY1 decouples growth from metabolism to enable robust fermentation without division. Comparing phosphoproteomic changes across ira2Δ and bcy1Δ strains implicated regulatory changes linked to xylose-dependent growth versus metabolism. Together, our results present a picture of the metabolic logic behind anaerobic xylose flux and suggest that widespread cellular remodeling, rather than individual metabolic changes, is an important goal for metabolic engineering.
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Affiliation(s)
- Kevin S. Myers
- Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Nicholas M. Riley
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Matthew E. MacGilvray
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Trey K. Sato
- Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Mick McGee
- Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Justin Heilberger
- Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Joshua J. Coon
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, United States of America
- Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, WI, United States of America
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI, United States of America
- Morgridge Institute for Research, Madison, WI, United States of America
| | - Audrey P. Gasch
- Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, United States of America
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI, United States of America
- Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, WI, United States of America
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Alsina D, Purroy R, Ros J, Tamarit J. Iron in Friedreich Ataxia: A Central Role in the Pathophysiology or an Epiphenomenon? Pharmaceuticals (Basel) 2018; 11:E89. [PMID: 30235822 PMCID: PMC6161073 DOI: 10.3390/ph11030089] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 09/15/2018] [Accepted: 09/17/2018] [Indexed: 12/16/2022] Open
Abstract
Friedreich ataxia is a neurodegenerative disease with an autosomal recessive inheritance. In most patients, the disease is caused by the presence of trinucleotide GAA expansions in the first intron of the frataxin gene. These expansions cause the decreased expression of this mitochondrial protein. Many evidences indicate that frataxin deficiency causes the deregulation of cellular iron homeostasis. In this review, we will discuss several hypotheses proposed for frataxin function, their caveats, and how they could provide an explanation for the deregulation of iron homeostasis found in frataxin-deficient cells. We will also focus on the potential mechanisms causing cellular dysfunction in Friedreich Ataxia and on the potential use of the iron chelator deferiprone as a therapeutic agent for this disease.
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Affiliation(s)
- David Alsina
- Departament de Ciències Mèdiques Bàsiques, IRBLleida, Universitat de Lleida, 25198 Lleida, Spain.
| | - Rosa Purroy
- Departament de Ciències Mèdiques Bàsiques, IRBLleida, Universitat de Lleida, 25198 Lleida, Spain.
| | - Joaquim Ros
- Departament de Ciències Mèdiques Bàsiques, IRBLleida, Universitat de Lleida, 25198 Lleida, Spain.
| | - Jordi Tamarit
- Departament de Ciències Mèdiques Bàsiques, IRBLleida, Universitat de Lleida, 25198 Lleida, Spain.
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Alsina D, Ros J, Tamarit J. Nitric oxide prevents Aft1 activation and metabolic remodeling in frataxin-deficient yeast. Redox Biol 2018; 14:131-141. [PMID: 28918000 PMCID: PMC5602528 DOI: 10.1016/j.redox.2017.09.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 08/25/2017] [Accepted: 09/02/2017] [Indexed: 11/30/2022] Open
Abstract
Yeast frataxin homolog (Yfh1) is the orthologue of human frataxin, a mitochondrial protein whose deficiency causes Friedreich Ataxia. Yfh1 deficiency activates Aft1, a transcription factor governing iron homeostasis in yeast cells. Although the mechanisms causing this activation are not completely understood, it is assumed that it may be caused by iron-sulfur deficiency. However, several evidences indicate that activation of Aft1 occurs in the absence of iron-sulfur deficiency. Besides, Yfh1 deficiency also leads to metabolic remodeling (mainly consisting in a shift from respiratory to fermentative metabolism) and to induction of Yhb1, a nitric oxide (NO) detoxifying enzyme. In this work, we have used conditional Yfh1 mutant yeast strains to investigate the relationship between NO, Aft1 activation and metabolic remodeling. We have observed that NO prevents Aft1 activation caused by Yfh1 deficiency. This phenomenon is not observed when Aft1 is activated by iron scarcity or impaired iron-sulfur biogenesis. In addition, analyzing key metabolic proteins by a targeted proteomics approach, we have observed that NO prevents the metabolic remodeling caused by Yfh1 deficiency. We conclude that Aft1 activation in Yfh1-deficient yeasts is not caused by iron-sulfur deficiency or iron scarcity. Our hypothesis is that Yfh1 deficiency leads to the presence of anomalous iron species that can compromise iron bioavailability and activate a signaling cascade that results in Aft1 activation and metabolic remodeling.
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Affiliation(s)
- David Alsina
- Departament de Ciències Mèdiques Bàsiques, IRBLleida, Universitat de Lleida, Lleida, Spain
| | - Joaquim Ros
- Departament de Ciències Mèdiques Bàsiques, IRBLleida, Universitat de Lleida, Lleida, Spain
| | - Jordi Tamarit
- Departament de Ciències Mèdiques Bàsiques, IRBLleida, Universitat de Lleida, Lleida, Spain.
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Edenharter O, Schneuwly S, Navarro JA. Mitofusin-Dependent ER Stress Triggers Glial Dysfunction and Nervous System Degeneration in a Drosophila Model of Friedreich's Ataxia. Front Mol Neurosci 2018; 11:38. [PMID: 29563863 PMCID: PMC5845754 DOI: 10.3389/fnmol.2018.00038] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 01/29/2018] [Indexed: 11/13/2022] Open
Abstract
Friedreich's ataxia (FRDA) is the most important recessive ataxia in the Caucasian population. It is caused by a deficit of the mitochondrial protein frataxin. Despite its pivotal effect on biosynthesis of iron-sulfur clusters and mitochondrial energy production, little is known about the influence of frataxin depletion on homeostasis of the cellular mitochondrial network. We have carried out a forward genetic screen to analyze genetic interactions between genes controlling mitochondrial homeostasis and Drosophila frataxin. Our screen has identified silencing of Drosophila mitofusin (Marf) as a suppressor of FRDA phenotypes in glia. Drosophila Marf is known to play crucial roles in mitochondrial fusion, mitochondrial degradation and in the interface between mitochondria and endoplasmic reticulum (ER). Thus, we have analyzed the effects of frataxin knockdown on mitochondrial morphology, mitophagy and ER function in our fly FRDA model using different histological and molecular markers such as tetramethylrhodamine, ethyl ester (TMRE), mitochondria-targeted GFP (mitoGFP), p62, ATG8a, LAMP1, Xbp1 and BiP/GRP78. Furthermore, we have generated the first Drosophila transgenic line containing the mtRosella construct under the UAS control to study the progression of the mitophagy process in vivo. Our results indicated that frataxin-deficiency had a small impact on mitochondrial morphology but enhanced mitochondrial clearance and altered the ER stress response in Drosophila. Remarkably, we demonstrate that downregulation of Marf suppresses ER stress in frataxin-deficient cells and this is sufficient to improve locomotor dysfunction, brain degeneration and lipid dyshomeostasis in our FRDA model. In agreement, chemical reduction of ER stress by means of two different compounds was sufficient to ameliorate the effects of frataxin deficiency in three different fly FRDA models. Altogether, our results strongly suggest that the protection mediated by Marf knockdown in glia is mainly linked to its role in the mitochondrial-ER tethering and not to mitochondrial dynamics or mitochondrial degradation and that ER stress is a novel and pivotal player in the progression and etiology of FRDA. This work might define a new pathological mechanism in FRDA, linking mitochondrial dysfunction due to frataxin deficiency and mitofusin-mediated ER stress, which might be responsible for characteristic cellular features of the disease and also suggests ER stress as a therapeutic target.
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Affiliation(s)
- Oliver Edenharter
- Department of Developmental Biology, Institute of Zoology, University of Regensburg, Regensburg, Germany
| | - Stephan Schneuwly
- Department of Developmental Biology, Institute of Zoology, University of Regensburg, Regensburg, Germany
| | - Juan A. Navarro
- Department of Developmental Biology, Institute of Zoology, University of Regensburg, Regensburg, Germany
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Lupoli F, Vannocci T, Longo G, Niccolai N, Pastore A. The role of oxidative stress in Friedreich's ataxia. FEBS Lett 2018; 592:718-727. [PMID: 29197070 PMCID: PMC5887922 DOI: 10.1002/1873-3468.12928] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2017] [Revised: 11/24/2017] [Accepted: 11/27/2017] [Indexed: 12/12/2022]
Abstract
Oxidative stress and an increase in the levels of free radicals are important markers associated with several pathologies, including Alzheimer's disease, cancer and diabetes. Friedreich's ataxia (FRDA) is an excellent paradigmatic example of a disease in which oxidative stress plays an important, albeit incompletely understood, role. FRDA is a rare genetic neurodegenerative disease that involves the partial silencing of frataxin, a small mitochondrial protein that was completely overlooked before being linked to FRDA. More than 20 years later, we now know how important this protein is in terms of being an essential and vital part of the machinery that produces iron-sulfur clusters in the cell. In this review, we revisit the most important steps that have brought us to our current understanding of the function of frataxin and its role in disease. We discuss the current hypotheses on the role of oxidative stress in FRDA and review some of the existing animal and cellular models. We also evaluate new techniques that can assist in the study of the disease mechanisms, as well as in our understanding of the interplay between primary and secondary phenotypes.
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Affiliation(s)
- Federica Lupoli
- Department of Biotechnology, Chemistry and PharmacyUniversity of SienaItaly
| | - Tommaso Vannocci
- The Maurice Wohl InstituteDementia Research CentreKing's College LondonUK
| | | | - Neri Niccolai
- Department of Biotechnology, Chemistry and PharmacyUniversity of SienaItaly
| | - Annalisa Pastore
- The Maurice Wohl InstituteDementia Research CentreKing's College LondonUK
- Department of Molecular MedicineUniversity of PaviaItaly
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11
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Britti E, Delaspre F, Feldman A, Osborne M, Greif H, Tamarit J, Ros J. Frataxin-deficient neurons and mice models of Friedreich ataxia are improved by TAT-MTScs-FXN treatment. J Cell Mol Med 2018; 22:834-848. [PMID: 28980774 PMCID: PMC5783845 DOI: 10.1111/jcmm.13365] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 07/28/2017] [Indexed: 01/02/2023] Open
Abstract
Friedreich ataxia (FA) is a rare disease caused by deficiency of frataxin, a mitochondrial protein. As there is no cure available for this disease, many strategies have been developed to reduce the deleterious effects of such deficiency. One of these approaches is based on delivering frataxin to the tissues by coupling the protein to trans-activator of transcription (TAT) peptides, which enables cell membranes crossing. In this study, we tested the efficiency of TAT-MTScs-FXN fusion protein to decrease neurodegeneration markers on frataxin-depleted neurons obtained from dorsal root ganglia (DRG), one of the most affected tissues. In mice models of the disease, we tested the ability of TAT-MTScs-FXN to penetrate the mitochondria and its effect on lifespan. In DRG neurons, treatment with TAT-MTScs-FXN increased cell survival, decreased neurite degeneration and reduced apoptotic markers, such as α-fodrin cleavage and caspase 9 activation. Also, we show that heat-shock protein 60 (HSP60), a molecular chaperone targeted to mitochondria, suffered an impaired processing in frataxin-deficient neurons that was relieved by TAT-MTScs-FXN addition. In mice models of the disease, administration of TAT-MTScs-FXN was able to reach muscle mitochondria, restore the activity of the succinate dehydrogenase and produce a significant lifespan increase. These results support the use of TAT-MTScs-FXN as a treatment for Friedreich ataxia.
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Affiliation(s)
- Elena Britti
- Departament de Ciències Mèdiques BàsiquesIRBLleidaUniversitat de LleidaLleidaSpain
| | - Fabien Delaspre
- Departament de Ciències Mèdiques BàsiquesIRBLleidaUniversitat de LleidaLleidaSpain
| | | | | | | | - Jordi Tamarit
- Departament de Ciències Mèdiques BàsiquesIRBLleidaUniversitat de LleidaLleidaSpain
| | - Joaquim Ros
- Departament de Ciències Mèdiques BàsiquesIRBLleidaUniversitat de LleidaLleidaSpain
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12
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Exploring the power of yeast to model aging and age-related neurodegenerative disorders. Biogerontology 2016; 18:3-34. [PMID: 27804052 DOI: 10.1007/s10522-016-9666-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 10/24/2016] [Indexed: 12/12/2022]
Abstract
Aging is a multifactorial process determined by molecular, cellular and systemic factors and it is well established that advancing age is a leading risk factor for several neurodegenerative diseases. In fact, the close association of aging and neurodegenerative disorders has placed aging as the greatest social and economic challenge of the 21st century, and age-related diseases have also become a key priority for countries worldwide. The growing need to better understand both aging and neurodegenerative processes has led to the development of simple eukaryotic models amenable for mechanistic studies. Saccharomyces cerevisiae has proven to be an unprecedented experimental model to study the fundamental aspects of aging and to decipher the intricacies of neurodegenerative disorders greatly because the molecular mechanisms underlying these processes are evolutionarily conserved from yeast to human. Moreover, yeast offers several methodological advantages allowing a rapid and relatively easy way of establishing gene-protein-function associations. Here we review different aging theories, common cellular pathways driving aging and neurodegenerative diseases and discuss the major contributions of yeast to the state-of-art knowledge in both research fields.
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13
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Sato TK, Tremaine M, Parreiras LS, Hebert AS, Myers KS, Higbee AJ, Sardi M, McIlwain SJ, Ong IM, Breuer RJ, Avanasi Narasimhan R, McGee MA, Dickinson Q, La Reau A, Xie D, Tian M, Reed JL, Zhang Y, Coon JJ, Hittinger CT, Gasch AP, Landick R. Directed Evolution Reveals Unexpected Epistatic Interactions That Alter Metabolic Regulation and Enable Anaerobic Xylose Use by Saccharomyces cerevisiae. PLoS Genet 2016; 12:e1006372. [PMID: 27741250 PMCID: PMC5065143 DOI: 10.1371/journal.pgen.1006372] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 09/19/2016] [Indexed: 11/25/2022] Open
Abstract
The inability of native Saccharomyces cerevisiae to convert xylose from plant biomass into biofuels remains a major challenge for the production of renewable bioenergy. Despite extensive knowledge of the regulatory networks controlling carbon metabolism in yeast, little is known about how to reprogram S. cerevisiae to ferment xylose at rates comparable to glucose. Here we combined genome sequencing, proteomic profiling, and metabolomic analyses to identify and characterize the responsible mutations in a series of evolved strains capable of metabolizing xylose aerobically or anaerobically. We report that rapid xylose conversion by engineered and evolved S. cerevisiae strains depends upon epistatic interactions among genes encoding a xylose reductase (GRE3), a component of MAP Kinase (MAPK) signaling (HOG1), a regulator of Protein Kinase A (PKA) signaling (IRA2), and a scaffolding protein for mitochondrial iron-sulfur (Fe-S) cluster biogenesis (ISU1). Interestingly, the mutation in IRA2 only impacted anaerobic xylose consumption and required the loss of ISU1 function, indicating a previously unknown connection between PKA signaling, Fe-S cluster biogenesis, and anaerobiosis. Proteomic and metabolomic comparisons revealed that the xylose-metabolizing mutant strains exhibit altered metabolic pathways relative to the parental strain when grown in xylose. Further analyses revealed that interacting mutations in HOG1 and ISU1 unexpectedly elevated mitochondrial respiratory proteins and enabled rapid aerobic respiration of xylose and other non-fermentable carbon substrates. Our findings suggest a surprising connection between Fe-S cluster biogenesis and signaling that facilitates aerobic respiration and anaerobic fermentation of xylose, underscoring how much remains unknown about the eukaryotic signaling systems that regulate carbon metabolism. The yeast Saccharomyces cerevisiae is being genetically engineered to produce renewable biofuels from sustainable plant material. Efficient biofuel production from plant material requires conversion of the complex suite of sugars found in plant material, including the five-carbon sugar xylose. Because it does not efficiently metabolize xylose, S. cerevisiae has been engineered with a minimal set of genes that should overcome this problem; however, additional genetic changes are required for optimal fermentative conversion of xylose into biofuel. Despite extensive knowledge of the regulatory networks controlling glucose metabolism, less is known about the regulation of xylose metabolism and how to rewire these networks for effective biofuel production. Here we report genetic mutations that enabled the conversion of xylose into bioethanol by a previously ineffective yeast strain. By comparing altered protein and metabolite abundance within yeast cells containing these mutations, we determined that the mutations synergistically alter metabolic pathways to improve the rate of xylose conversion. One change in a gene with well-characterized aerobic mitochondrial functions was found to play an unexpected role in anaerobic conversion of xylose into ethanol. The results of this work will allow others to rapidly generate yeast strains for the conversion of xylose into biofuels and other products.
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Affiliation(s)
- Trey K. Sato
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- * E-mail: (TKS); (APG); (RL)
| | - Mary Tremaine
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Lucas S. Parreiras
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Alexander S. Hebert
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Kevin S. Myers
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Alan J. Higbee
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Maria Sardi
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Sean J. McIlwain
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Irene M. Ong
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Rebecca J. Breuer
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Ragothaman Avanasi Narasimhan
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Mick A. McGee
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Quinn Dickinson
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Alex La Reau
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Dan Xie
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Mingyuan Tian
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Jennifer L. Reed
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Yaoping Zhang
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Joshua J. Coon
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Chris Todd Hittinger
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Wisconsin Energy Institute, J.F. Crow Institute for the Study of Evolution, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Audrey P. Gasch
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- * E-mail: (TKS); (APG); (RL)
| | - Robert Landick
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- * E-mail: (TKS); (APG); (RL)
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14
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Cardarelli S, D'Amici S, Tassone P, Tramonti A, Uccelletti D, Mancini P, Saliola M. Characterization of the transcription factor encoding gene, KlADR1: metabolic role in Kluyveromyces lactis and expression in Saccharomyces cerevisiae. MICROBIOLOGY-SGM 2016; 162:1933-1944. [PMID: 27655407 DOI: 10.1099/mic.0.000374] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In Saccharomyces cerevisiae, Adr1 is a zinc-finger transcription factor involved in the transcriptional activation of ADH2. Deletion of KlADR1, its putative ortholog in Kluyveromyces lactis, led to reduced growth in glycerol, oleate and yeast extract-peptone medium suggesting, as in S. cerevisiae, its requirement for glycerol, fatty acid and nitrogen utilization. Moreover, growth comparison on yeast extract and peptone plates showed in K. lactis a KlAdr1-dependent growth trait not present in S. cerevisiae, indicating different metabolic roles of the two factors in their environmental niches. KlADR1 is required for growth under respiratory and fermentative conditions like KlADH, alcohol dehydrogenase genes necessary for metabolic adaptation during the growth transition. Using in-gel native alcohol dehydrogenase assay, we showed that this factor affected the Adh pattern by altering the balance between these activities. Since the activity most affected by KlAdr1 is KlAdh3, a deletion analysis of the KlADH3 promoter allowed the isolation of a DNA fragment through which KlAdr1 modulated its expression. The expression of the KlADR1-GFP gene allowed the intracellular localization of the factor in K. lactis and S. cerevisiae, suggesting in the two yeasts a common mechanism of KlAdr1 translocation under fermentative and respiratory conditions. Finally, the chimeric Kl/ScADR1 gene encoding the zinc-finger domains of KlAdr1 fused to the transactivating domains of the S. cerevisiae factor activated in Scadr1Δ the transcription of ADH2 in a ScAdr1-dependent fashion.
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Affiliation(s)
- Silvia Cardarelli
- Department of Biology and Biotechnology 'C. Darwin', Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | - Sirio D'Amici
- Department of Biology and Biotechnology 'C. Darwin', Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | - Paola Tassone
- Department of Biology and Biotechnology 'C. Darwin', Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | - Angela Tramonti
- CNR Department of Biochemical Sciences 'Rossi Fanelli', Istituto di Biologia e Patologia Molecolari, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | - Daniela Uccelletti
- Department of Biology and Biotechnology 'C. Darwin', Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | - Patrizia Mancini
- Department of Experimental Medicine, Sapienza University of Rome, Viale Regina Elena 324, 00161 Rome, Italy
| | - Michele Saliola
- Department of Biology and Biotechnology 'C. Darwin', Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy
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15
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Cth2 Protein Mediates Early Adaptation of Yeast Cells to Oxidative Stress Conditions. PLoS One 2016; 11:e0148204. [PMID: 26824473 PMCID: PMC4732752 DOI: 10.1371/journal.pone.0148204] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Accepted: 01/14/2016] [Indexed: 11/19/2022] Open
Abstract
Cth2 is an mRNA-binding protein that participates in remodeling yeast cell metabolism in iron starvation conditions by promoting decay of the targeted molecules, in order to avoid excess iron consumption. This study shows that in the absence of Cth2 immediate upregulation of expression of several of the iron regulon genes (involved in high affinity iron uptake and intracellular iron redistribution) upon oxidative stress by hydroperoxide is more intense than in wild type conditions where Cth2 is present. The oxidative stress provokes a temporary increase in the levels of Cth2 (itself a member of the iron regulon). In such conditions Cth2 molecules accumulate at P bodies-like structures when the constitutive mRNA decay machinery is compromised. In addition, a null Δcth2 mutant shows defects, in comparison to CTH2 wild type cells, in exit from α factor-induced arrest at the G1 stage of the cell cycle when hydroperoxide treatment is applied. The cell cycle defects are rescued in conditions that compromise uptake of external iron into the cytosol. The observations support a role of Cth2 in modulating expression of diverse iron regulon genes, excluding those specifically involved in the reductive branch of the high-affinity transport. This would result in immediate adaptation of the yeast cells to an oxidative stress, by controlling uptake of oxidant-promoting iron cations.
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16
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Obis È, Irazusta V, Sanchís D, Ros J, Tamarit J. Frataxin deficiency in neonatal rat ventricular myocytes targets mitochondria and lipid metabolism. Free Radic Biol Med 2014; 73:21-33. [PMID: 24751525 DOI: 10.1016/j.freeradbiomed.2014.04.016] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 04/04/2014] [Accepted: 04/04/2014] [Indexed: 11/21/2022]
Abstract
Friedreich ataxia (FRDA) is a hereditary disease caused by deficient frataxin expression. This mitochondrial protein has been related to iron homeostasis, energy metabolism, and oxidative stress. Patients with FRDA experience neurologic alterations and cardiomyopathy, which is the leading cause of death. The specific effects of frataxin depletion on cardiomyocytes are poorly understood because no appropriate cardiac cellular model is available to researchers. To address this research need, we present a model based on primary cultures of neonatal rat ventricular myocytes (NRVMs) and short-hairpin RNA interference. Using this approach, frataxin was reduced down to 5 to 30% of control protein levels after 7 days of transduction. At this stage the activity and amount of the iron-sulfur protein aconitase, in vitro activities of several OXPHOS components, levels of iron-regulated mRNAs, and the ATP/ADP ratio were comparable to controls. However, NRVMs exhibited markers of oxidative stress and a disorganized mitochondrial network with enlarged mitochondria. Lipids, the main energy source of heart cells, also underwent a clear metabolic change, indicated by the increased presence of lipid droplets and induction of medium-chain acyl-CoA dehydrogenase. These results indicate that mitochondria and lipid metabolism are primary targets of frataxin deficiency in NRVMs. Therefore, they contribute to the understanding of cardiac-specific mechanisms occurring in FRDA and give clues for the design of cardiac-specific treatment strategies for FRDA.
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MESH Headings
- Aconitate Hydratase/metabolism
- Animals
- Cardiomyopathies/pathology
- Cells, Cultured
- Disease Models, Animal
- Friedreich Ataxia/pathology
- Heart Ventricles/cytology
- Heart Ventricles/metabolism
- Humans
- Iron-Binding Proteins/genetics
- Lipid Metabolism/genetics
- Membrane Potential, Mitochondrial/physiology
- Mitochondria, Heart/genetics
- Mitochondria, Heart/metabolism
- Mitochondria, Heart/pathology
- Myocytes, Cardiac/cytology
- Myocytes, Cardiac/metabolism
- Oxidative Stress/physiology
- Peroxisome Proliferator-Activated Receptors/metabolism
- RNA Interference
- RNA, Small Interfering
- Rats
- Rats, Sprague-Dawley
- Frataxin
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Affiliation(s)
- Èlia Obis
- Departament de Ciències Mèdiques Bàsiques, IRB-Lleida, Universitat de Lleida, 25198 Lleida, Spain
| | - Verónica Irazusta
- Instituto de Investigación para la Industria Química, INIQUI-CONICET, Salta, Argentina
| | - Daniel Sanchís
- Departament de Ciències Mèdiques Bàsiques, IRB-Lleida, Universitat de Lleida, 25198 Lleida, Spain
| | - Joaquim Ros
- Departament de Ciències Mèdiques Bàsiques, IRB-Lleida, Universitat de Lleida, 25198 Lleida, Spain
| | - Jordi Tamarit
- Departament de Ciències Mèdiques Bàsiques, IRB-Lleida, Universitat de Lleida, 25198 Lleida, Spain.
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