1
|
Dutta T, Sasidharan K, Ciociola E, Pennisi G, Noto FR, Kovooru L, Kroon T, Lindblom A, Du Y, Pirmoradian M, Wallin S, Mancina RM, Lindén D, Romeo S. Mitochondrial amidoxime-reducing component 1 p.Ala165Thr increases protein degradation mediated by the proteasome. Liver Int 2024; 44:1219-1232. [PMID: 38375985 DOI: 10.1111/liv.15857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 01/15/2024] [Accepted: 01/19/2024] [Indexed: 02/21/2024]
Abstract
OBJECTIVE Metabolic dysfunction-associated steatotic liver disease (MASLD) is a global health concern with no effective and specific drug treatment available. The rs2642438 minor allele in mitochondrial amidoxime-reducing component 1 (MARC1) results in an aminoacidic substitution (p.Ala165Thr) and associates with protection against MASLD. However, the mechanisms behind this protective effect are unknown. In this study, we examined the consequences of this aminoacidic substitution on protein stability and subcellular localization. METHODS We overexpressed the human MARC1 A165 (wild-type) or 165T (mutant) in vivo in mice and in vitro in human hepatoma cells (HepG2 and HuH-7), generated several mutants at position 165 by in situ mutagenesis and then examined protein levels. We also generated HepG2 cells stably overexpressing MARC1 A165 or 165T to test the effect of this substitution on MARC1 subcellular localization. RESULTS MARC1 165T overexpression resulted in lower protein levels than A165 both in vivo and in vitro. Similarly, any mutant at position 165 showed lower protein levels compared to the wild-type protein. We showed that the 165T mutant protein is polyubiquitinated and its degradation is accelerated through lysine-48 ubiquitin-mediated proteasomal degradation. We also showed that the 165T substitution does not affect the MARC1 subcellular localization. CONCLUSIONS This study shows that alanine at position 165 in MARC1 is crucial for protein stability, and the threonine substitution at this position leads to a hypomorphic protein variant due to lower protein levels. Our result supports the notion that lowering hepatic MARC1 protein level may be a successful therapeutic strategy for treating MASLD.
Collapse
Affiliation(s)
- Tanmoy Dutta
- Department of Molecular and Clinical Medicine, Institute of Medicine, The Sahlgrenska Academy, Wallenberg Laboratory, University of Gothenburg, Gothenburg, Sweden
| | - Kavitha Sasidharan
- Department of Molecular and Clinical Medicine, Institute of Medicine, The Sahlgrenska Academy, Wallenberg Laboratory, University of Gothenburg, Gothenburg, Sweden
| | - Ester Ciociola
- Department of Molecular and Clinical Medicine, Institute of Medicine, The Sahlgrenska Academy, Wallenberg Laboratory, University of Gothenburg, Gothenburg, Sweden
| | - Grazia Pennisi
- Department of Molecular and Clinical Medicine, Institute of Medicine, The Sahlgrenska Academy, Wallenberg Laboratory, University of Gothenburg, Gothenburg, Sweden
- Section of Gastroenterology and Hepatology, Dipartimento Di Promozione Della Salute, Materno Infantile, Medicina Interna e Specialistica Di Eccellenza (PROMISE), University of Palermo, Palermo, Italy
| | - Francesca R Noto
- Department of Molecular and Clinical Medicine, Institute of Medicine, The Sahlgrenska Academy, Wallenberg Laboratory, University of Gothenburg, Gothenburg, Sweden
- Department of Medical and Surgical Sciences, University Magna Graecia, Catanzaro, Italy
| | - Lohitesh Kovooru
- Department of Molecular and Clinical Medicine, Institute of Medicine, The Sahlgrenska Academy, Wallenberg Laboratory, University of Gothenburg, Gothenburg, Sweden
| | - Tobias Kroon
- Bioscience Metabolism, Research and Early Development Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Anna Lindblom
- Bioscience Metabolism, Research and Early Development Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Yue Du
- Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom
| | - Mohammad Pirmoradian
- Translational Science and Experimental Medicine, Research and Early Development Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Simonetta Wallin
- Bioscience Metabolism, Research and Early Development Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Rosellina M Mancina
- Department of Molecular and Clinical Medicine, Institute of Medicine, The Sahlgrenska Academy, Wallenberg Laboratory, University of Gothenburg, Gothenburg, Sweden
| | - Daniel Lindén
- Bioscience Metabolism, Research and Early Development Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
- Division of Endocrinology, Department of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, Institute of Medicine, The Sahlgrenska Academy, Wallenberg Laboratory, University of Gothenburg, Gothenburg, Sweden
- Department of Medical and Surgical Sciences, University Magna Graecia, Catanzaro, Italy
- Department of Cardiology, Sahlgrenska University Hospital, Gothenburg, Sweden
| |
Collapse
|