1
|
Leo G, Leone P, Ataie Kachoie E, Tolomeo M, Galluccio M, Indiveri C, Barile M, Capaldi S. Structural insights into the bifunctional enzyme human FAD synthase. Structure 2024:S0969-2126(24)00132-1. [PMID: 38688286 DOI: 10.1016/j.str.2024.04.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 03/20/2024] [Accepted: 04/03/2024] [Indexed: 05/02/2024]
Abstract
Human flavin adenine dinucleotide synthase (hFADS) is a bifunctional, multi-domain enzyme that exhibits both flavin mononucleotide adenylyltransferase and pyrophosphatase activities. Here we report the crystal structure of full-length hFADS2 and its C-terminal PAPS domain in complex with flavin adenine dinucleotide (FAD), and dissect the structural determinants underlying the contribution of each individual domain, within isoforms 1 and 2, to each of the two enzymatic activities. Structural and functional characterization performed on complete or truncated constructs confirmed that the C-terminal domain tightly binds FAD and catalyzes its synthesis, while the combination of the N-terminal molybdopterin-binding and KH domains is the minimal essential substructure required for the hydrolysis of FAD and other ADP-containing dinucleotides. hFADS2 associates in a stable C2-symmetric dimer, in which the packing of the KH domain of one protomer against the N-terminal domain of the other creates the adenosine-specific active site responsible for the hydrolytic activity.
Collapse
Affiliation(s)
- Giulia Leo
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Piero Leone
- Department of Biosciences, Biotechnology and Environment, University of Bari, via Orabona 4, 70126 Bari, Italy
| | - Elham Ataie Kachoie
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Maria Tolomeo
- Department of Biosciences, Biotechnology and Environment, University of Bari, via Orabona 4, 70126 Bari, Italy; Department of Biology, Ecology and Earth Sciences (DiBEST), Laboratory of Biochemistry, Molecular Biotechnology, and Molecular Biology, University of Calabria, via P. Bucci 4c, 6c, 87036 Arcavacata di Rende, Italy
| | - Michele Galluccio
- Department of Biology, Ecology and Earth Sciences (DiBEST), Laboratory of Biochemistry, Molecular Biotechnology, and Molecular Biology, University of Calabria, via P. Bucci 4c, 6c, 87036 Arcavacata di Rende, Italy
| | - Cesare Indiveri
- Department of Biology, Ecology and Earth Sciences (DiBEST), Laboratory of Biochemistry, Molecular Biotechnology, and Molecular Biology, University of Calabria, via P. Bucci 4c, 6c, 87036 Arcavacata di Rende, Italy; National Research Council (CNR), Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), via Amendola 122/O, 70126 Bari, Italy
| | - Maria Barile
- Department of Biosciences, Biotechnology and Environment, University of Bari, via Orabona 4, 70126 Bari, Italy.
| | - Stefano Capaldi
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy.
| |
Collapse
|
2
|
Tummolo A, Carella R, De Giovanni D, Paterno G, Simonetti S, Tolomeo M, Leone P, Barile M. Micronutrient Deficiency in Inherited Metabolic Disorders Requiring Diet Regimen: A Brief Critical Review. Int J Mol Sci 2023; 24:17024. [PMID: 38069347 PMCID: PMC10707160 DOI: 10.3390/ijms242317024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 11/28/2023] [Accepted: 11/29/2023] [Indexed: 12/18/2023] Open
Abstract
Many inherited metabolic disorders (IMDs), including disorders of amino acid, fatty acid, and carbohydrate metabolism, are treated with a dietary reduction or exclusion of certain macronutrients, putting one at risk of a reduced intake of micronutrients. In this review, we aim to provide available evidence on the most common micronutrient deficits related to specific dietary approaches and on the management of their deficiency, in the meanwhile discussing the main critical points of each nutritional supplementation. The emerging concepts are that a great heterogeneity in clinical practice exists, as well as no univocal evidence on the most common micronutrient abnormalities. In phenylketonuria, for example, micronutrients are recommended to be supplemented through protein substitutes; however, not all formulas are equally supplemented and some of them are not added with micronutrients. Data on pyridoxine and riboflavin status in these patients are particularly scarce. In long-chain fatty acid oxidation disorders, no specific recommendations on micronutrient supplementation are available. Regarding carbohydrate metabolism disorders, the difficult-to-ascertain sugar content in supplementation formulas is still a matter of concern. A ketogenic diet may predispose one to both oligoelement deficits and their overload, and therefore deserves specific formulations. In conclusion, our overview points out the lack of unanimous approaches to micronutrient deficiencies, the need for specific formulations for IMDs, and the necessity of high-quality studies, particularly for some under-investigated deficits.
Collapse
Affiliation(s)
- Albina Tummolo
- Department of Metabolic Diseases, Clinical Genetics and Diabetology, Giovanni XXIII Children Hospital, Azienda Ospedaliero-Universitaria Consorziale, 70126 Bari, Italy; (R.C.); (D.D.G.); (G.P.)
| | - Rosa Carella
- Department of Metabolic Diseases, Clinical Genetics and Diabetology, Giovanni XXIII Children Hospital, Azienda Ospedaliero-Universitaria Consorziale, 70126 Bari, Italy; (R.C.); (D.D.G.); (G.P.)
| | - Donatella De Giovanni
- Department of Metabolic Diseases, Clinical Genetics and Diabetology, Giovanni XXIII Children Hospital, Azienda Ospedaliero-Universitaria Consorziale, 70126 Bari, Italy; (R.C.); (D.D.G.); (G.P.)
| | - Giulia Paterno
- Department of Metabolic Diseases, Clinical Genetics and Diabetology, Giovanni XXIII Children Hospital, Azienda Ospedaliero-Universitaria Consorziale, 70126 Bari, Italy; (R.C.); (D.D.G.); (G.P.)
| | - Simonetta Simonetti
- Regional Centre for Neonatal Screening, Department of Clinical Pathology and Neonatal Screening, Children’s Hospital “Giovanni XXIII”, Azienda Ospedaliero-Universitaria Consorziale, 70126 Bari, Italy;
| | - Maria Tolomeo
- Department of Biosciences, Biotechnology and Environment, University of Bari “A. Moro”, via Orabona 4, 70125 Bari, Italy; (M.T.); (P.L.)
- Department of DiBEST (Biologia, Ecologia e Scienze della Terra), University of Calabria, via P. Bucci 4C, 87036 Arcavacata di Rende, Italy
| | - Piero Leone
- Department of Biosciences, Biotechnology and Environment, University of Bari “A. Moro”, via Orabona 4, 70125 Bari, Italy; (M.T.); (P.L.)
| | - Maria Barile
- Department of Biosciences, Biotechnology and Environment, University of Bari “A. Moro”, via Orabona 4, 70125 Bari, Italy; (M.T.); (P.L.)
| |
Collapse
|
3
|
Ben Mariem O, Saporiti S, Guerrini U, Laurenzi T, Palazzolo L, Indiveri C, Barile M, De Fabiani E, Eberini I. In silico investigation on structure-function relationship of members belonging to the human SLC52 transporter family. Proteins 2022; 91:619-633. [PMID: 36511838 DOI: 10.1002/prot.26453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 11/18/2022] [Accepted: 12/08/2022] [Indexed: 12/15/2022]
Abstract
Riboflavin is an essential water-soluble vitamin that needs to be provided through the diet because of the conversion into flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN), important cofactors in hundreds of flavoenzymes. The adsorption and distribution of riboflavin is mediated by transmembrane transporters of the SLC52 family, namely RFVT1-3, whose mutations are mainly associated with two diseases, MADD and the Brown-Vialetto-Van Laere syndrome. Interest in RFVTs as pharmacological targets has increased in the last few years due to their overexpression in several cancer cells, which can be exploited both by blocking the uptake of riboflavin into the cancerous cells, and by performing cancer targeted delivery of drugs with a high affinity for RFVTs. In this work, we propose three-dimensional structural models for all three human riboflavin transporters obtained by state-of-the-art artificial intelligence-based methods, which were then further refined with molecular dynamics simulations. Furthermore, two of the most notable mutations concerning RFVT2 and RFVT3 (W31S and N21S, respectively) were investigated studying the interactions between the wild-type and mutated transporters with riboflavin.
Collapse
Affiliation(s)
- Omar Ben Mariem
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Via Giuseppe Balzaretti 9, Milan, Italy
| | - Simona Saporiti
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Via Giuseppe Balzaretti 9, Milan, Italy
| | - Uliano Guerrini
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Via Giuseppe Balzaretti 9, Milan, Italy
| | - Tommaso Laurenzi
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Via Giuseppe Balzaretti 9, Milan, Italy
| | - Luca Palazzolo
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Via Giuseppe Balzaretti 9, Milan, Italy
| | - Cesare Indiveri
- CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), Bari, Italy.,Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via P. Bucci cubo 4C, Arcavacata di Rende, Italy
| | - Maria Barile
- Department of Biosciences, Biotechnology and Biopharmaceutics, University of Bari A.Moro, Bari, Italy
| | - Emma De Fabiani
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Via Giuseppe Balzaretti 9, Milan, Italy
| | - Ivano Eberini
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Via Giuseppe Balzaretti 9, Milan, Italy.,DSRC, Università degli Studi di Milano, Milan, Italy
| |
Collapse
|
4
|
Zhao X, Tebbe L, Naash MI, Al-Ubaidi MR. The Neuroprotective Role of Retbindin, a Metabolic Regulator in the Neural Retina. Front Pharmacol 2022; 13:919667. [PMID: 35873559 PMCID: PMC9298789 DOI: 10.3389/fphar.2022.919667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 06/10/2022] [Indexed: 11/13/2022] Open
Abstract
Dysregulation of retinal metabolism is emerging as one of the major reasons for many inherited retinal diseases (IRDs), a leading cause of blindness worldwide. Thus, the identification of a common regulator that can preserve or revert the metabolic ecosystem to homeostasis is a key step in developing a treatment for different forms of IRDs. Riboflavin (RF) and its derivatives (flavins), flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD), are essential cofactors for a wide range of cellular metabolic processes; hence, they are particularly critical in highly metabolically active tissues such as the retina. Patients with RF deficiency (ariboflavinosis) often display poor photosensitivity resulting in impaired low-light vision. We have identified a novel retina-specific RF binding protein called retbindin (Rtbdn), which plays a key role in retaining flavin levels in the neural retina. This role is mediated by its specific localization at the interface between the neural retina and retinal pigment epithelium (RPE), which is essential for metabolite and nutrient exchange. As a consequence of this vital function, Rtbdn's role in flavin utilization and metabolism in retinal degeneration is discussed. The principal findings are that Rtbdn helps maintain high levels of retinal flavins, and its ablation leads to an early-onset retinal metabolic dysregulation, followed by progressive degeneration of rod and cone photoreceptors. Lack of Rtbdn reduces flavin levels, forcing the neural retina to repurpose glucose to reduce the production of free radicals during ATP production. This leads to metabolic breakdown followed by retinal degeneration. Assessment of the role of Rtbdn in several preclinical retinal disease models revealed upregulation of its levels by several folds prior to and during the degenerative process. Ablation of Rtbdn in these models accelerated the rate of retinal degeneration. In agreement with these in vivo studies, we have also demonstrated that Rtbdn protects immortalized cone photoreceptor cells (661W cells) from light damage in vitro. This indicates that Rtbdn plays a neuroprotective role during retinal degeneration. Herein, we discussed the specific function of Rtbdn and its neuroprotective role in retinal metabolic homeostasis and its role in maintaining retinal health.
Collapse
Affiliation(s)
| | | | - Muna I. Naash
- Department of Biomedical Engineering, University of Houston, Houston, TX, United States
| | - Muayyad R. Al-Ubaidi
- Department of Biomedical Engineering, University of Houston, Houston, TX, United States
| |
Collapse
|
5
|
Tolomeo M, Chimienti G, Lanza M, Barbaro R, Nisco A, Latronico T, Leone P, Petrosillo G, Liuzzi GM, Ryder B, Inbar-Feigenberg M, Colella M, Lezza AMS, Olsen RKJ, Barile M. Retrograde response to mitochondrial dysfunctions associated to LOF variations in FLAD1 exon 2: unraveling the importance of RFVT2. Free Radic Res 2022; 56:511-525. [PMID: 36480241 DOI: 10.1080/10715762.2022.2146501] [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: 12/13/2022]
Abstract
Flavin adenine dinucleotide (FAD) synthase (EC 2.7.7.2), encoded by human flavin adenine dinucleotide synthetase 1 (FLAD1), catalyzes the last step of the pathway converting riboflavin (Rf) into FAD. FLAD1 variations were identified as a cause of LSMFLAD (lipid storage myopathy due to FAD synthase deficiency, OMIM #255100), resembling Multiple Acyl-CoA Dehydrogenase Deficiency, sometimes treatable with high doses of Rf; no alternative therapeutic strategies are available. We describe here cell morphological and mitochondrial alterations in dermal fibroblasts derived from a LSMFLAD patient carrying a homozygous truncating FLAD1 variant (c.745C > T) in exon 2. Despite a severe decrease in FAD synthesis rate, the patient had decreased cellular levels of Rf and flavin mononucleotide and responded to Rf treatment. We hypothesized that disturbed flavin homeostasis and Rf-responsiveness could be due to a secondary impairment in the expression of the Rf transporter 2 (RFVT2), encoded by SLC52A2, in the frame of an adaptive retrograde signaling to mitochondrial dysfunction. Interestingly, an antioxidant response element (ARE) is found in the region upstream of the transcriptional start site of SLC52A2. Accordingly, we found that abnormal mitochondrial morphology and impairments in bioenergetics were accompanied by increased cellular reactive oxygen species content and mtDNA oxidative damage. Concomitantly, an active response to mitochondrial stress is suggested by increased levels of PPARγ-co-activator-1α and Peroxiredoxin III. In this scenario, the treatment with high doses of Rf might compensate for the secondary RFVT2 molecular defect, providing a molecular rationale for the Rf responsiveness in patients with loss of function variants in FLAD1 exon 2.HIGHLIGHTSFAD synthase deficiency alters mitochondrial morphology and bioenergetics;FAD synthase deficiency triggers a mitochondrial retrograde response;FAD synthase deficiency evokes nuclear signals that adapt the expression of RFVT2.
Collapse
Affiliation(s)
- Maria Tolomeo
- Department of Biosciences, Biotechnologies, and Environment, University of Bari Aldo Moro, Bari, Italy.,Department of DiBEST (Biologia, Ecologia e Scienze della Terra), University of Calabria, Arcavacata di Rende, Italy
| | - Guglielmina Chimienti
- Department of Biosciences, Biotechnologies, and Environment, University of Bari Aldo Moro, Bari, Italy
| | - Martina Lanza
- Department of Biosciences, Biotechnologies, and Environment, University of Bari Aldo Moro, Bari, Italy
| | - Roberto Barbaro
- Department of Biosciences, Biotechnologies, and Environment, University of Bari Aldo Moro, Bari, Italy
| | - Alessia Nisco
- Department of Biosciences, Biotechnologies, and Environment, University of Bari Aldo Moro, Bari, Italy
| | - Tiziana Latronico
- Department of Biosciences, Biotechnologies, and Environment, University of Bari Aldo Moro, Bari, Italy
| | - Piero Leone
- Department of Biosciences, Biotechnologies, and Environment, University of Bari Aldo Moro, Bari, Italy
| | - Giuseppe Petrosillo
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), National Research Council (CNR), Bari, Italy
| | - Grazia Maria Liuzzi
- Department of Biosciences, Biotechnologies, and Environment, University of Bari Aldo Moro, Bari, Italy
| | - Bryony Ryder
- National Metabolic Service, Starship Children's Hospital, Auckland, New Zealand
| | - Michal Inbar-Feigenberg
- Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, University of Toronto, Toronto, Canada
| | - Matilde Colella
- Department of Biosciences, Biotechnologies, and Environment, University of Bari Aldo Moro, Bari, Italy
| | - Angela M S Lezza
- Department of Biosciences, Biotechnologies, and Environment, University of Bari Aldo Moro, Bari, Italy
| | - Rikke K J Olsen
- Research Unit for Molecular Medicine, Department for Clinical Medicine, Aarhus University and Aarhus University Hospital, Aarhus, Denmark
| | - Maria Barile
- Department of Biosciences, Biotechnologies, and Environment, University of Bari Aldo Moro, Bari, Italy
| |
Collapse
|
6
|
Colasuonno F, Marioli C, Tartaglia M, Bertini E, Compagnucci C, Moreno S. New Insights into the Neurodegeneration Mechanisms Underlying Riboflavin Transporter Deficiency (RTD): Involvement of Energy Dysmetabolism and Cytoskeletal Derangement. Biomedicines 2022; 10:biomedicines10061329. [PMID: 35740351 PMCID: PMC9219947 DOI: 10.3390/biomedicines10061329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 05/26/2022] [Accepted: 05/30/2022] [Indexed: 01/18/2023] Open
Abstract
Riboflavin transporter deficiency (RTD) is a rare genetic disorder characterized by motor, sensory and cranial neuropathy. This childhood-onset neurodegenerative disease is caused by biallelic pathogenic variants in either SLC52A2 or SLC52A3 genes, resulting in insufficient supply of riboflavin (vitamin B2) and consequent impairment of flavoprotein-dependent metabolic pathways. Current therapy, empirically based high-dose riboflavin supplementation, ameliorates the progression of the disease, even though response to treatment is variable and partial. Recent studies have highlighted concurrent pathogenic contribution of cellular energy dysmetabolism and cytoskeletal derangement. In this context, patient specific RTD models, based on induced pluripotent stem cell (iPSC) technology, have provided evidence of redox imbalance, involving mitochondrial and peroxisomal dysfunction. Such oxidative stress condition likely causes cytoskeletal perturbation, associated with impaired differentiation of RTD motor neurons. In this review, we discuss the most recent findings obtained using different RTD models. Relevantly, the integration of data from innovative iPSC-derived in vitro models and invertebrate in vivo models may provide essential information on RTD pathophysiology. Such novel insights are expected to suggest custom therapeutic strategies, especially for those patients unresponsive to high-dose riboflavin treatments.
Collapse
Affiliation(s)
- Fiorella Colasuonno
- Genetics and Rare Diseases Research Division, Bambino Gesù Children’s Hospital, IRCCS, 00165 Rome, Italy; (F.C.); (C.M.); (M.T.); (E.B.)
- Department of Science, LIME, University Roma Tre, 00165 Rome, Italy
| | - Chiara Marioli
- Genetics and Rare Diseases Research Division, Bambino Gesù Children’s Hospital, IRCCS, 00165 Rome, Italy; (F.C.); (C.M.); (M.T.); (E.B.)
- Department of Science, LIME, University Roma Tre, 00165 Rome, Italy
| | - Marco Tartaglia
- Genetics and Rare Diseases Research Division, Bambino Gesù Children’s Hospital, IRCCS, 00165 Rome, Italy; (F.C.); (C.M.); (M.T.); (E.B.)
| | - Enrico Bertini
- Genetics and Rare Diseases Research Division, Bambino Gesù Children’s Hospital, IRCCS, 00165 Rome, Italy; (F.C.); (C.M.); (M.T.); (E.B.)
| | - Claudia Compagnucci
- Genetics and Rare Diseases Research Division, Bambino Gesù Children’s Hospital, IRCCS, 00165 Rome, Italy; (F.C.); (C.M.); (M.T.); (E.B.)
- Correspondence: (C.C.); (S.M.)
| | - Sandra Moreno
- Department of Science, LIME, University Roma Tre, 00165 Rome, Italy
- Correspondence: (C.C.); (S.M.)
| |
Collapse
|
7
|
Tummolo A, Leone P, Tolomeo M, Solito R, Mattiuzzo M, Lepri FR, Lorè T, Cardinali R, De Giovanni D, Simonetti S, Barile M. Combined
isobutyryl‐CoA
and multiple
acyl‐CoA
dehydrogenase deficiency in a boy with altered riboflavin homeostasis. JIMD Rep 2022; 63:276-291. [PMID: 35822092 PMCID: PMC9259400 DOI: 10.1002/jmd2.12292] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 04/07/2022] [Accepted: 04/12/2022] [Indexed: 11/24/2022] Open
Abstract
In this report, we describe the case of an 11‐year‐old boy, who came to our attention for myalgia and muscle weakness, associated with inappetence and vomiting. Hypertransaminasemia was also noted, with ultrasound evidence of hepatomegaly. Biochemical investigations revealed acylcarnitine and organic acid profiles resembling those seen in MADD, that is, multiple acyl‐CoA dehydrogenase deficiencies (OMIM #231680) a rare inherited disorder of fatty acids, amino acids, and choline metabolism. The patient carried a single pathogenetic variant in the ETFDH gene (c.524G>A, p.Arg175His) and no pathogenetic variant in the riboflavin (Rf) homeostasis related genes (SLC52A1, SLC52A2, SLC52A3, SLC25A32, FLAD1). Instead, compound heterozygosity was found in the ACAD8 gene (c.512C>G, p.Ser171Cys; c.822C>A, p.Asn274Lys), coding for isobutyryl‐CoA dehydrogenase (IBD), whose pathogenic variants are associated to IBD deficiency (OMIM #611283), a rare autosomal recessive disorder of valine catabolism. The c.822C>A was never previously described in a patient. Subsequent further analyses of Rf homeostasis showed reduced levels of flavins in plasma and altered FAD‐dependent enzymatic activities in erythrocytes, as well as a significant reduction in the level of the plasma membrane Rf transporter 2 in erythrocytes. The observed Rf/flavin scarcity in this patient, possibly associated with a decreased ETF:QO efficiency might be responsible for the observed MADD‐like phenotype. The patient's clinical picture improved after supplementation of Rf, l‐carnitine, Coenzyme Q10, and also 3OH‐butyrate. This report demonstrates that, even in the absence of genetic defects in genes involved in Rf homeostasis, further targeted molecular analysis may reveal secondary and possibly treatable biochemical alterations in this pattern.
Collapse
Affiliation(s)
- Albina Tummolo
- Metabolic Diseases and Clinical Genetics Unit Children's Hospital “Giovanni XXIII” Bari Italy
| | - Piero Leone
- Department of Biosciences, Biotechnology and Biopharmaceutics University of Bari “A. Moro” Bari Italy
| | - Maria Tolomeo
- Department of Biosciences, Biotechnology and Biopharmaceutics University of Bari “A. Moro” Bari Italy
| | - Rita Solito
- Department of Biosciences, Biotechnology and Biopharmaceutics University of Bari “A. Moro” Bari Italy
| | - Matteo Mattiuzzo
- Laboratory of Medical Genetics Translational Cytogenomics Research Unit, Bambino Gesù Children Hospital Rome Italy
| | - Francesca Romana Lepri
- Laboratory of Medical Genetics Translational Cytogenomics Research Unit, Bambino Gesù Children Hospital Rome Italy
| | - Tania Lorè
- Regional Centre for Neonatal Screening Children's Hospital “Giovanni XXIII” Bari Italy
| | - Roberta Cardinali
- Regional Centre for Neonatal Screening Children's Hospital “Giovanni XXIII” Bari Italy
| | - Donatella De Giovanni
- Metabolic Diseases and Clinical Genetics Unit Children's Hospital “Giovanni XXIII” Bari Italy
| | - Simonetta Simonetti
- Regional Centre for Neonatal Screening Children's Hospital “Giovanni XXIII” Bari Italy
| | - Maria Barile
- Department of Biosciences, Biotechnology and Biopharmaceutics University of Bari “A. Moro” Bari Italy
| |
Collapse
|
8
|
Leone P, Tolomeo M, Piancone E, Puzzovio PG, De Giorgi C, Indiveri C, Di Schiavi E, Barile M. Mimicking human riboflavin responsive neuromuscular disorders by silencing flad-1 gene in C. elegans: Alteration of vitamin transport and cholinergic transmission. IUBMB Life 2021; 74:672-683. [PMID: 34558787 PMCID: PMC9292511 DOI: 10.1002/iub.2553] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Revised: 08/14/2021] [Accepted: 08/30/2021] [Indexed: 01/01/2023]
Abstract
Riboflavin (Rf), or vitamin B2, is the precursor of FMN and FAD, redox cofactors of several dehydrogenases involved in energy metabolism, redox balance and other cell regulatory processes. FAD synthase, coded by FLAD1 gene in humans, is the last enzyme in the pathway converting Rf into FAD. Mutations in FLAD1 gene are responsible for neuromuscular disorders, in some cases treatable with Rf. In order to mimic these disorders, the Caenorhabditis elegans (C. elegans) gene orthologue of FLAD1 (flad‐1) was silenced in a model strain hypersensitive to RNA interference in nervous system. Silencing flad‐1 resulted in a significant decrease in total flavin content, paralleled by a decrease in the level of the FAD‐dependent ETFDH protein and by a secondary transcriptional down‐regulation of the Rf transporter 1 (rft‐1) possibly responsible for the total flavin content decrease. Conversely an increased ETFDH mRNA content was found. These biochemical changes were accompanied by significant phenotypical changes, including impairments of fertility and locomotion due to altered cholinergic transmission, as indicated by the increased sensitivity to aldicarb. A proposal is made that neuronal acetylcholine production/release is affected by alteration of Rf homeostasis. Rf supplementation restored flavin content, increased rft‐1 transcript levels and eliminated locomotion defects. In this aspect, C. elegans could provide a low‐cost animal model to elucidate the molecular rationale for Rf therapy in human Rf responsive neuromuscular disorders and to screen other molecules with therapeutic potential.
Collapse
Affiliation(s)
- Piero Leone
- Department of Biosciences, Biotechnology, and Biopharmaceutics, University of Bari, Bari, Italy
| | - Maria Tolomeo
- Department of Biosciences, Biotechnology, and Biopharmaceutics, University of Bari, Bari, Italy
| | - Elisabetta Piancone
- Department of Biosciences, Biotechnology, and Biopharmaceutics, University of Bari, Bari, Italy
| | - Pier Giorgio Puzzovio
- Faculty of Medicine, Pharmacology and Experimental Therapeutics Unit, Institute for Drug Research, School of Pharmacy, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Carla De Giorgi
- Department of Biosciences, Biotechnology, and Biopharmaceutics, University of Bari, Bari, Italy
| | - Cesare Indiveri
- Department DiBEST (Biologia, Ecologia, Scienze della Terra), Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Arcavacata di Rende, Italy
| | - Elia Di Schiavi
- Institute of Biosciences and Bioresources (IBBR) CNR, Naples, Italy
| | - Maria Barile
- Department of Biosciences, Biotechnology, and Biopharmaceutics, University of Bari, Bari, Italy
| |
Collapse
|
9
|
Bruni F, Giancaspero TA, Oreb M, Tolomeo M, Leone P, Boles E, Roberti M, Caselle M, Barile M. Subcellular Localization of Fad1p in Saccharomyces cerevisiae: A Choice at Post-Transcriptional Level? Life (Basel) 2021; 11:life11090967. [PMID: 34575116 PMCID: PMC8470081 DOI: 10.3390/life11090967] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 09/06/2021] [Accepted: 09/13/2021] [Indexed: 11/24/2022] Open
Abstract
FAD synthase is the last enzyme in the pathway that converts riboflavin into FAD. In Saccharomyces cerevisiae, the gene encoding for FAD synthase is FAD1, from which a sole protein product (Fad1p) is expected to be generated. In this work, we showed that a natural Fad1p exists in yeast mitochondria and that, in its recombinant form, the protein is able, per se, to both enter mitochondria and to be destined to cytosol. Thus, we propose that FAD1 generates two echoforms—that is, two identical proteins addressed to different subcellular compartments. To shed light on the mechanism underlying the subcellular destination of Fad1p, the 3′ region of FAD1 mRNA was analyzed by 3′RACE experiments, which revealed the existence of (at least) two FAD1 transcripts with different 3′UTRs, the short one being 128 bp and the long one being 759 bp. Bioinformatic analysis on these 3′UTRs allowed us to predict the existence of a cis-acting mitochondrial localization motif, present in both the transcripts and, presumably, involved in protein targeting based on the 3′UTR context. Here, we propose that the long FAD1 transcript might be responsible for the generation of mitochondrial Fad1p echoform.
Collapse
Affiliation(s)
- Francesco Bruni
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari Aldo Moro, Via Orabona 4, 70125 Bari, Italy; (F.B.); (T.A.G.); (M.T.); (P.L.); (M.R.)
| | - Teresa Anna Giancaspero
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari Aldo Moro, Via Orabona 4, 70125 Bari, Italy; (F.B.); (T.A.G.); (M.T.); (P.L.); (M.R.)
| | - Mislav Oreb
- Institute of Molecular Biosciences, Goethe-University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt am Main, Germany; (M.O.); (E.B.)
| | - Maria Tolomeo
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari Aldo Moro, Via Orabona 4, 70125 Bari, Italy; (F.B.); (T.A.G.); (M.T.); (P.L.); (M.R.)
| | - Piero Leone
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari Aldo Moro, Via Orabona 4, 70125 Bari, Italy; (F.B.); (T.A.G.); (M.T.); (P.L.); (M.R.)
| | - Eckhard Boles
- Institute of Molecular Biosciences, Goethe-University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt am Main, Germany; (M.O.); (E.B.)
| | - Marina Roberti
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari Aldo Moro, Via Orabona 4, 70125 Bari, Italy; (F.B.); (T.A.G.); (M.T.); (P.L.); (M.R.)
| | - Michele Caselle
- Physics Department, University of Turin and INFN, Via P. Giuria 1, 10125 Turin, Italy;
| | - Maria Barile
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari Aldo Moro, Via Orabona 4, 70125 Bari, Italy; (F.B.); (T.A.G.); (M.T.); (P.L.); (M.R.)
- Correspondence: ; Tel.: +39-080-544-3604
| |
Collapse
|
10
|
Alteration of Flavin Cofactor Homeostasis in Human Neuromuscular Pathologies. Methods Mol Biol 2021; 2280:275-295. [PMID: 33751442 DOI: 10.1007/978-1-0716-1286-6_18] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The aim of this short review chapter is to provide a brief summary of the relevance of riboflavin (Rf or vitamin B2) and its derived cofactors flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) for human neuromuscular bioenergetics.Therefore, as a completion of this book we would like to summarize what kind of human pathologies could derive from genetic disturbances of Rf transport, flavin cofactor synthesis and delivery to nascent apoflavoproteins, as well as by alteration of vitamin recycling during protein turnover.
Collapse
|
11
|
Mereis M, Wanders RJA, Schoonen M, Dercksen M, Smuts I, van der Westhuizen FH. Disorders of flavin adenine dinucleotide metabolism: MADD and related deficiencies. Int J Biochem Cell Biol 2020; 132:105899. [PMID: 33279678 DOI: 10.1016/j.biocel.2020.105899] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 11/27/2020] [Accepted: 11/30/2020] [Indexed: 12/13/2022]
Abstract
Multiple acyl-coenzyme A dehydrogenase deficiency (MADD), or glutaric aciduria type II (GAII), is a group of clinically heterogeneous disorders caused by mutations in electron transfer flavoprotein (ETF) and ETF-ubiquinone oxidoreductase (ETFQO) - the two enzymes responsible for the re-oxidation of enzyme-bound flavin adenine dinucleotide (FADH2) via electron transfer to the respiratory chain at the level of coenzyme Q10. Over the past decade, an increasing body of evidence has further coupled mutations in FAD metabolism (including intercellular riboflavin transport, FAD biosynthesis and FAD transport) to MADD-like phenotypes. In this review we provide a detailed description of the overarching and specific metabolic pathways involved in MADD. We examine the eight associated genes (ETFA, ETFB, ETFDH, FLAD1, SLC25A32 and SLC52A1-3) and clinical phenotypes, and report ∼436 causative mutations following a systematic literature review. Finally, we focus attention on the value and shortcomings of current diagnostic approaches, as well as current and future therapeutic options for MADD and its phenotypic disorders.
Collapse
Affiliation(s)
- Michelle Mereis
- Human Metabolomics, North-West University, Potchefstroom, South Africa
| | - Ronald J A Wanders
- Department of Clinical Chemistry, Laboratory Genetic Metabolic Diseases, Amsterdam University Medical Centre, University of Amsterdam, Amsterdam, the Netherlands
| | - Maryke Schoonen
- Human Metabolomics, North-West University, Potchefstroom, South Africa; Centre of Excellence for Nutrition, North-West University, Potchefstroom, South Africa
| | - Marli Dercksen
- Human Metabolomics, North-West University, Potchefstroom, South Africa
| | - Izelle Smuts
- Department of Paediatrics, Steve Biko Academic Hospital, University of Pretoria, South Africa
| | | |
Collapse
|
12
|
Functional Recovery of a GCDH Variant Associated to Severe Deflavinylation—Molecular Insights into Potential Beneficial Effects of Riboflavin Supplementation in Glutaric Aciduria-Type I Patients. Int J Mol Sci 2020; 21:ijms21197063. [PMID: 32992790 PMCID: PMC7583906 DOI: 10.3390/ijms21197063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 09/21/2020] [Accepted: 09/22/2020] [Indexed: 11/16/2022] Open
Abstract
Riboflavin is the biological precursor of two important flavin cofactors—flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN)—that are critical prosthetic groups in several redox enzymes. While dietary supplementation with riboflavin is a recognized support therapy in several inborn errors of metabolism, it has yet unproven benefits in several other pathologies affecting flavoproteins. This is the case for glutaric aciduria type I (GA-I), a rare neurometabolic disorder associated with mutations in the GCDH gene, which encodes for glutaryl-coenzyme A (CoA) dehydrogenase (GCDH). Although there are a few reported clinical cases that have responded to riboflavin intake, there is still not enough molecular evidence supporting therapeutic recommendation. Hence, it is necessary to elucidate the molecular basis in favor of riboflavin supplementation in GA-I patients. Here, using a combination of biochemical and biophysical methodologies, we investigate the clinical variant GCDH-p.Val400Met as a model for a phenotype associated with severe deflavinylation. Through a systematic analysis, we establish that recombinant human GCDH-p.Val400Met is expressed in a nonfunctional apo form, which is mainly monomeric rather than tetrameric. However, we show that exogenous FAD is a driver for structural reorganization of the mutant enzyme with concomitant functional recovery, improved thermolability, and resistance to trypsin digestion. Overall, these results establish proof of principle for the beneficial effects of riboflavin supplementation in GA-I patients.
Collapse
|