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Hendriks WJAJ, van Cruchten RTP, Pulido R. Hereditable variants of classical protein tyrosine phosphatase genes: Will they prove innocent or guilty? Front Cell Dev Biol 2023; 10:1051311. [PMID: 36755664 PMCID: PMC9900141 DOI: 10.3389/fcell.2022.1051311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 12/28/2022] [Indexed: 01/24/2023] Open
Abstract
Protein tyrosine phosphatases, together with protein tyrosine kinases, control many molecular signaling steps that control life at cellular and organismal levels. Impairing alterations in the genes encoding the involved proteins is expected to profoundly affect the quality of life-if compatible with life at all. Here, we review the current knowledge on the effects of germline variants that have been reported for genes encoding a subset of the protein tyrosine phosphatase superfamily; that of the thirty seven classical members. The conclusion must be that the newest genome research tools produced an avalanche of data that suggest 'guilt by association' for individual genes to specific disorders. Future research should face the challenge to investigate these accusations thoroughly and convincingly, to reach a mature genotype-phenotype map for this intriguing protein family.
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Affiliation(s)
- Wiljan J. A. J. Hendriks
- Department of Cell Biology, Radboud University Medical Centre, Nijmegen, The Netherlands,*Correspondence: Wiljan J. A. J. Hendriks,
| | | | - Rafael Pulido
- Biomarkers in Cancer Unit, Biocruces Bizkaia Health Research Institute, Barakaldo, Spain,Ikerbasque, Basque Foundation for Science, Bilbao, Spain
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van Cruchten RTP, van As D, Glennon JC, van Engelen BGM, 't Hoen PAC, Wenninger S, Daidj F, Cumming S, Littleford R, Monckton DG, Lochmüller H, Catt M, Faber CG, Hapca A, Donnan PT, Gorman G, Bassez G, Schoser B, Knoop H, Treweek S, Wansink DG, Impens F, Gabriels R, Claeys T, Ravel-Chapuis A, Jasmin BJ, Mahon N, Nieuwenhuis S, Martens L, Novak P, Furling D, Baak A, Gourdon G, MacKenzie A, Martinat C, Neault N, Roos A, Duchesne E, Salz R, Thompson R, Baghdoyan S, Varghese AM, Blom P, Spendiff S, Manta A. Clinical improvement of DM1 patients reflected by reversal of disease-induced gene expression in blood. BMC Med 2022; 20:395. [PMID: 36352383 PMCID: PMC9646470 DOI: 10.1186/s12916-022-02591-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 09/30/2022] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Myotonic dystrophy type 1 (DM1) is an incurable multisystem disease caused by a CTG-repeat expansion in the DM1 protein kinase (DMPK) gene. The OPTIMISTIC clinical trial demonstrated positive and heterogenous effects of cognitive behavioral therapy (CBT) on the capacity for activity and social participations in DM1 patients. Through a process of reverse engineering, this study aims to identify druggable molecular biomarkers associated with the clinical improvement in the OPTIMISTIC cohort. METHODS Based on full blood samples collected during OPTIMISTIC, we performed paired mRNA sequencing for 27 patients before and after the CBT intervention. Linear mixed effect models were used to identify biomarkers associated with the disease-causing CTG expansion and the mean clinical improvement across all clinical outcome measures. RESULTS We identified 608 genes for which their expression was significantly associated with the CTG-repeat expansion, as well as 1176 genes significantly associated with the average clinical response towards the intervention. Remarkably, all 97 genes associated with both returned to more normal levels in patients who benefited the most from CBT. This main finding has been replicated based on an external dataset of mRNA data of DM1 patients and controls, singling these genes out as candidate biomarkers for therapy response. Among these candidate genes were DNAJB12, HDAC5, and TRIM8, each belonging to a protein family that is being studied in the context of neurological disorders or muscular dystrophies. Across the different gene sets, gene pathway enrichment analysis revealed disease-relevant impaired signaling in, among others, insulin-, metabolism-, and immune-related pathways. Furthermore, evidence for shared dysregulations with another neuromuscular disease, Duchenne muscular dystrophy, was found, suggesting a partial overlap in blood-based gene dysregulation. CONCLUSIONS DM1-relevant disease signatures can be identified on a molecular level in peripheral blood, opening new avenues for drug discovery and therapy efficacy assessments.
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Affiliation(s)
- Remco T P van Cruchten
- Center for Molecular and Biomolecular Informatics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Daniël van As
- Center for Molecular and Biomolecular Informatics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.,Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Jeffrey C Glennon
- Conway Institute of Biomolecular and Biomedical Research, School of Medicine, University College Dublin, Dublin, Ireland
| | - Baziel G M van Engelen
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Peter A C 't Hoen
- Center for Molecular and Biomolecular Informatics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.
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Degener MJF, van Cruchten RTP, Otero BA, Wang ET, Wansink DG, 't Hoen PAC. A comprehensive atlas of fetal splicing patterns in the brain of adult myotonic dystrophy type 1 patients. NAR Genom Bioinform 2022; 4:lqac016. [PMID: 35274098 PMCID: PMC8903011 DOI: 10.1093/nargab/lqac016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 01/28/2022] [Accepted: 02/13/2022] [Indexed: 11/14/2022] Open
Abstract
In patients with myotonic dystrophy type 1 (DM1), dysregulation of RNA-binding proteins like MBNL and CELF1 leads to alternative splicing of exons and is thought to induce a return to fetal splicing patterns in adult tissues, including the central nervous system (CNS). To comprehensively evaluate this, we created an atlas of developmentally regulated splicing patterns in the frontal cortex of healthy individuals and DM1 patients, by combining RNA-seq data from BrainSpan, GTEx and DM1 patients. Thirty-four splice events displayed an inclusion pattern in DM1 patients that is typical for the fetal situation in healthy individuals. The regulation of DM1-relevant splicing patterns could partly be explained by changes in mRNA expression of the splice regulators MBNL1, MBNL2 and CELF1. On the contrary, interindividual differences in splicing patterns between healthy adults could not be explained by differential expression of these splice regulators. Our findings lend transcriptome-wide evidence to the previously noted shift to fetal splicing patterns in the adult DM1 brain as a consequence of an imbalance in antagonistic MBNL and CELF1 activities. Our atlas serves as a solid foundation for further study and understanding of the cognitive phenotype in patients.
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Affiliation(s)
- Max J F Degener
- Centre for Molecular and Biomolecular Informatics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Remco T P van Cruchten
- Centre for Molecular and Biomolecular Informatics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Brittney A Otero
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics, Genetics Institute, University of Florida, FL 32610-0266 Gainesville, FL, USA
| | - Eric T Wang
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics, Genetics Institute, University of Florida, FL 32610-0266 Gainesville, FL, USA
| | - Derick G Wansink
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Peter A C 't Hoen
- Centre for Molecular and Biomolecular Informatics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
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van Cruchten RTP, Wansink DG. In Vitro Synthesis and RNA Structure Probing of CUG Triplet Repeat RNA. Methods Mol Biol 2020; 2056:187-202. [PMID: 31586349 DOI: 10.1007/978-1-4939-9784-8_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Aberrant RNA structure plays a central role in the molecular mechanisms guided by repeat RNAs in diseases like myotonic dystrophy (DM), C9orf72-linked amyotrophic lateral sclerosis (ALS) and fragile X tremor/ataxia syndrome (FXTAS). Much knowledge remains to be gained about how these repeat-expanded transcripts are actually folded, especially regarding the properties specific to very long and interrupted repeats. RNA structure can be interrogated by chemical as well as enzymatic probes. These probes usually bind or cleave single-stranded nucleotides, which can subsequently be detected using reverse transcriptase primer extension. In this chapter, we describe methodology for in vitro synthesis and structure probing of expanded CUG repeat RNAs associated with DM type 1 and approaches for the associated data analysis.
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Affiliation(s)
- Remco T P van Cruchten
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Derick G Wansink
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.
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André LM, van Cruchten RTP, Willemse M, Wansink DG. (CTG)n repeat-mediated dysregulation of MBNL1 and MBNL2 expression during myogenesis in DM1 occurs already at the myoblast stage. PLoS One 2019; 14:e0217317. [PMID: 31116797 PMCID: PMC6530876 DOI: 10.1371/journal.pone.0217317] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 05/08/2019] [Indexed: 11/18/2022] Open
Abstract
Myotonic dystrophy type 1 (DM1) is a severe neuromuscular disorder caused by the expression of trinucleotide repeat-containing DMPK transcripts. Abnormally expanded (CUG)n repeats in these transcripts form hairpin-like structures that cause the RNA to accumulate in the cell nucleus by sequestering isoforms of the Muscleblind (MBNL) family, tissue-specific regulators of developmentally programmed, post-transcriptional processes in RNA metabolism. Through this mechanism, the function of MBNL in RNA processing becomes dominantly perturbed, which eventually leads to aberrant alternative splicing and the expression of foetal splice variants of a wide variety of proteins, including the MBNL isoforms themselves. Here, we employ a patient-derived muscle cell model for DM1 to examine in detail the expression of MBNL RNA and protein variants during myogenic differentiation. This DM1 model consists of a panel of isogenic myoblast cell lines that either contain a pathogenic DMPK allele with a congenital mutation of 2600 triplets, or lack this expanded repeat through CRISPR/Cas9-mediated gene editing. We found that the temporal expression levels of MBNL1, MBNL2 and MBNL3 RNAs are not influenced by presence of the (CTG)2600 repeat during myogenesis in vitro. However, throughout myoblast proliferation and differentiation to myotubes a disproportionate inclusion of MBNL1 exon 5 and MBNL2 exons 5 and 8 occurs in cells with the (CTG)2600 repeat. As a consequence, a reduced quantity and imbalanced collection of splice variants of MBNL1 and MBNL2 accumulates in both the cytoplasm and the nucleus of DM1 myoblasts and myotubes. We thus propose that both the quantitative and qualitative changes in the intracellular partitioning of MBNL proteins are a pivotal cause of skeletal muscle problems in DM1, starting already in muscle progenitor cells.
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Affiliation(s)
- Laurène M. André
- Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Department of Cell Biology, Nijmegen, The Netherlands
| | - Remco T. P. van Cruchten
- Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Department of Cell Biology, Nijmegen, The Netherlands
| | - Marieke Willemse
- Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Department of Cell Biology, Nijmegen, The Netherlands
| | - Derick G. Wansink
- Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Department of Cell Biology, Nijmegen, The Netherlands
- * E-mail:
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van Cruchten RTP, Wieringa B, Wansink DG. Expanded CUG repeats in DMPK transcripts adopt diverse hairpin conformations without influencing the structure of the flanking sequences. RNA 2019; 25:481-495. [PMID: 30700578 PMCID: PMC6426290 DOI: 10.1261/rna.068940.118] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 01/24/2019] [Indexed: 06/09/2023]
Abstract
Myotonic dystrophy type 1 (DM1) is a complex neuromuscular disorder caused by expansion of a CTG repeat in the 3'-untranslated region (UTR) of the DMPK gene. Mutant DMPK transcripts form aberrant structures and anomalously associate with RNA-binding proteins (RBPs). As a first step toward better understanding of the involvement of abnormal DMPK mRNA folding in DM1 manifestation, we used SHAPE, DMS, CMCT, and RNase T1 structure probing in vitro for modeling of the topology of the DMPK 3'-UTR with normal and pathogenic repeat lengths of up to 197 CUG triplets. The resulting structural information was validated by disruption of base-pairing with LNA antisense oligonucleotides (AONs) and used for prediction of therapeutic AON accessibility and verification of DMPK knockdown efficacy in cells. Our model for DMPK RNA structure demonstrates that the hairpin formed by the CUG repeat has length-dependent conformational plasticity, with a structure that is guided by and embedded in an otherwise rigid architecture of flanking regions in the DMPK 3'-UTR. Evidence is provided that long CUG repeats may form not only single asymmetrical hairpins but also exist as branched structures. These newly identified structures have implications for DM1 pathogenic mechanisms, like sequestration of RBPs and repeat-associated non-AUG (RAN) translation.
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Affiliation(s)
- Remco T P van Cruchten
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, 6525 GA, The Netherlands
| | - Bé Wieringa
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, 6525 GA, The Netherlands
| | - Derick G Wansink
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, 6525 GA, The Netherlands
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Månsson C, van Cruchten RTP, Weininger U, Yang X, Cukalevski R, Arosio P, Dobson CM, Knowles T, Akke M, Linse S, Emanuelsson C. Conserved S/T Residues of the Human Chaperone DNAJB6 Are Required for Effective Inhibition of Aβ42 Amyloid Fibril Formation. Biochemistry 2018; 57:4891-4902. [DOI: 10.1021/acs.biochem.8b00353] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Cecilia Månsson
- Department of Biochemistry and Structural Biology, Center for Molecular Protein Science, Lund University, 221 00 Lund, Sweden
| | - Remco T. P. van Cruchten
- Department of Biochemistry and Structural Biology, Center for Molecular Protein Science, Lund University, 221 00 Lund, Sweden
| | - Ulrich Weininger
- Department of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, 221 00 Lund, Sweden
| | - Xiaoting Yang
- Department of Biochemistry and Structural Biology, Center for Molecular Protein Science, Lund University, 221 00 Lund, Sweden
| | - Risto Cukalevski
- Department of Biochemistry and Structural Biology, Center for Molecular Protein Science, Lund University, 221 00 Lund, Sweden
| | - Paolo Arosio
- Department of Chemistry and Center for Misfolding Diseases, University of Cambridge, Cambridge CB2 1EW, U.K
| | - Christopher M. Dobson
- Department of Chemistry and Center for Misfolding Diseases, University of Cambridge, Cambridge CB2 1EW, U.K
| | - Tuomas Knowles
- Department of Chemistry and Center for Misfolding Diseases, University of Cambridge, Cambridge CB2 1EW, U.K
- Cavendish Laboratory, Department of Physics, JJ Thomson Avenue, Cambridge CB3 0HE, U.K
| | - Mikael Akke
- Department of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, 221 00 Lund, Sweden
| | - Sara Linse
- Department of Biochemistry and Structural Biology, Center for Molecular Protein Science, Lund University, 221 00 Lund, Sweden
| | - Cecilia Emanuelsson
- Department of Biochemistry and Structural Biology, Center for Molecular Protein Science, Lund University, 221 00 Lund, Sweden
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Kakkar V, Månsson C, de Mattos EP, Bergink S, van der Zwaag M, van Waarde MAWH, Kloosterhuis NJ, Melki R, van Cruchten RTP, Al-Karadaghi S, Arosio P, Dobson CM, Knowles TPJ, Bates GP, van Deursen JM, Linse S, van de Sluis B, Emanuelsson C, Kampinga HH. The S/T-Rich Motif in the DNAJB6 Chaperone Delays Polyglutamine Aggregation and the Onset of Disease in a Mouse Model. Mol Cell 2016; 62:272-283. [PMID: 27151442 DOI: 10.1016/j.molcel.2016.03.017] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 01/14/2016] [Accepted: 03/10/2016] [Indexed: 01/30/2023]
Abstract
Expanded CAG repeats lead to debilitating neurodegenerative disorders characterized by aggregation of proteins with expanded polyglutamine (polyQ) tracts. The mechanism of aggregation involves primary and secondary nucleation steps. We show how a noncanonical member of the DNAJ-chaperone family, DNAJB6, inhibits the conversion of soluble polyQ peptides into amyloid fibrils, in particular by suppressing primary nucleation. This inhibition is mediated by a serine/threonine-rich region that provides an array of surface-exposed hydroxyl groups that bind to polyQ peptides and may disrupt the formation of the H bonds essential for the stability of amyloid fibrils. Early prevention of polyQ aggregation by DNAJB6 occurs also in cells and leads to delayed neurite retraction even before aggregates are visible. In a mouse model, brain-specific coexpression of DNAJB6 delays polyQ aggregation, relieves symptoms, and prolongs lifespan, pointing to DNAJB6 as a potential target for disease therapy and tool for unraveling early events in the onset of polyQ diseases.
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Affiliation(s)
- Vaishali Kakkar
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, the Netherlands
| | - Cecilia Månsson
- Department of Biochemistry and Structural Biology, Center for Molecular Protein Science, Lund University, 221 00 Lund, Sweden
| | - Eduardo P de Mattos
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, the Netherlands; Department of Genetics, Federal University of Rio Grande do Sul, Porto Alegre 91501-970, Brazil
| | - Steven Bergink
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, the Netherlands
| | - Marianne van der Zwaag
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, the Netherlands
| | - Maria A W H van Waarde
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, the Netherlands
| | - Niels J Kloosterhuis
- Department of Pediatrics, Molecular Genetics Section, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, the Netherlands
| | - Ronald Melki
- Neuroscience Paris-Saclay Institute of Neuroscience, Centre National de la Recherche Scientifique, 91190 Gif-Sur-Yvette, France
| | - Remco T P van Cruchten
- Department of Biochemistry and Structural Biology, Center for Molecular Protein Science, Lund University, 221 00 Lund, Sweden
| | - Salam Al-Karadaghi
- Department of Biochemistry and Structural Biology, Center for Molecular Protein Science, Lund University, 221 00 Lund, Sweden
| | - Paolo Arosio
- Department of Chemistry, University of Cambridge, Cambridge CB2 1TN, UK
| | | | | | - Gillian P Bates
- Department of Medical and Molecular Genetics, King's College London, London WC2R 2LS, UK
| | | | - Sara Linse
- Department of Biochemistry and Structural Biology, Center for Molecular Protein Science, Lund University, 221 00 Lund, Sweden
| | - Bart van de Sluis
- Department of Pediatrics, Molecular Genetics Section, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, the Netherlands
| | - Cecilia Emanuelsson
- Department of Biochemistry and Structural Biology, Center for Molecular Protein Science, Lund University, 221 00 Lund, Sweden
| | - Harm H Kampinga
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, the Netherlands.
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Hensen SMM, Boelens WC, Bonger KM, van Cruchten RTP, van Delft FL, Pruijn GJM. Phenylglyoxal-based visualization of citrullinated proteins on Western blots. Molecules 2015; 20:6592-600. [PMID: 25875038 PMCID: PMC6272700 DOI: 10.3390/molecules20046592] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 04/01/2015] [Accepted: 04/02/2015] [Indexed: 01/03/2023] Open
Abstract
Citrullination is the conversion of peptidylarginine to peptidylcitrulline, which is catalyzed by peptidylarginine deiminases. This conversion is involved in different physiological processes and is associated with several diseases, including cancer and rheumatoid arthritis. A common method to detect citrullinated proteins relies on anti-modified citrulline antibodies directed to a specific chemical modification of the citrulline side chain. Here, we describe a versatile, antibody-independent method for the detection of citrullinated proteins on a membrane, based on the selective reaction of phenylglyoxal with the ureido group of citrulline under highly acidic conditions. The method makes use of 4-azidophenylglyoxal, which, after reaction with citrullinated proteins, can be visualized with alkyne-conjugated probes. The sensitivity of this procedure, using an alkyne-biotin probe, appeared to be comparable to the antibody-based detection method and independent of the sequence surrounding the citrulline.
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Affiliation(s)
- Sanne M M Hensen
- Department of Biomolecular Chemistry, Institute for Molecules and Materials, Radboud Institute for Molecular Life Sciences and Netherlands Proteomics Centre, Radboud University Nijmegen, P.O. Box 9101, NL-6500 HB Nijmegen, The Netherlands.
| | - Wilbert C Boelens
- Department of Biomolecular Chemistry, Institute for Molecules and Materials, Radboud Institute for Molecular Life Sciences and Netherlands Proteomics Centre, Radboud University Nijmegen, P.O. Box 9101, NL-6500 HB Nijmegen, The Netherlands.
| | - Kimberly M Bonger
- Department of Biomolecular Chemistry, Institute for Molecules and Materials, Radboud Institute for Molecular Life Sciences and Netherlands Proteomics Centre, Radboud University Nijmegen, P.O. Box 9101, NL-6500 HB Nijmegen, The Netherlands.
| | - Remco T P van Cruchten
- Department of Biomolecular Chemistry, Institute for Molecules and Materials, Radboud Institute for Molecular Life Sciences and Netherlands Proteomics Centre, Radboud University Nijmegen, P.O. Box 9101, NL-6500 HB Nijmegen, The Netherlands.
| | - Floris L van Delft
- Department of Synthetic Organic Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, P.O. Box 9101, NL-6500 HB Nijmegen, The Netherlands.
| | - Ger J M Pruijn
- Department of Biomolecular Chemistry, Institute for Molecules and Materials, Radboud Institute for Molecular Life Sciences and Netherlands Proteomics Centre, Radboud University Nijmegen, P.O. Box 9101, NL-6500 HB Nijmegen, The Netherlands.
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