1
|
Capponi S, Stöffler N, Penney EB, Grütz K, Nizamuddin S, Vermunt MW, Castelijns B, Fernandez-Cerado C, Legarda GP, Velasco-Andrada MS, Muñoz EL, Ang MA, Diesta CCE, Creyghton MP, Klein C, Bragg DC, De Rijk P, Timmers HTM. Dissection of TAF1 neuronal splicing and implications for neurodegeneration in X-linked dystonia-parkinsonism. Brain Commun 2021; 3:fcab253. [PMID: 34746789 PMCID: PMC8567410 DOI: 10.1093/braincomms/fcab253] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 08/16/2021] [Accepted: 08/19/2021] [Indexed: 11/29/2022] Open
Abstract
X-linked dystonia-parkinsonism (XDP) is a monogenic neurodegenerative disorder of the basal ganglia, which presents as a combination of hyperkinetic movements and parkinsonian features. The underlying genetic mechanism involves the insertion of a SINE-VNTR-Alu retrotransposon within the TAF1 gene. Interestingly, alterations of TAF1 have been involved in multiple neurological diseases. In XDP, the SINE-VNTR-Alu insertion in TAF1 has been proposed to result in alternative splicing defects, including the decreased incorporation of a neuron-specific microexon annotated as 34′. This mechanism has become controversial as recent studies failed to provide support. In order to resolve this conundrum, we examined the alternative splicing patterns of TAF1 mRNAs in XDP and control brains. The impact of the disease-associated SINE-VNTR-Alu on alternative splicing of microexon 34′ was further investigated in cellular assays. Subsequently, microexon 34′ incorporation was explored by RT-PCR and Nanopore long-read sequencing of TAF1 mRNAs from XDP and control brains tissues. Using cell-based splicing assays, we demonstrate that presence of the disease-associated SINE-VNTR-Alu does not affect the inclusion of microexon 34′. In addition, we show that (1) microexon 34′-containing TAF1 mRNAs are detected at similar levels in XDP as in controls and that (2) the architecture of TAF1 transcripts is remarkably similar between XDP and controls brains. These results indicate that microexon 34′ incorporation into TAF1 mRNA is not affected in XDP brains. Our findings shift the current paradigm of XDP by discounting alternative splicing of TAF1 microexon 34′ as the molecular basis for this disease.
Collapse
Affiliation(s)
- Simona Capponi
- German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center (DKFZ), Department of Urology, Medical Center-University of Freiburg, 79106 Freiburg, Germany
| | - Nadja Stöffler
- German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center (DKFZ), Department of Urology, Medical Center-University of Freiburg, 79106 Freiburg, Germany
| | - Ellen B Penney
- The Collaborative Center for X-Linked Dystonia Parkinsonism (CCXDP), Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Karen Grütz
- Institute of Neurogenetics, University of Lübeck, Lübeck 23538, Germany
| | - Sheikh Nizamuddin
- German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center (DKFZ), Department of Urology, Medical Center-University of Freiburg, 79106 Freiburg, Germany
| | - Marit W Vermunt
- Erasmus University Medical Center, Department of Developmental Biology, Rotterdam 3015 GD, The Netherlands
| | - Bas Castelijns
- Erasmus University Medical Center, Department of Developmental Biology, Rotterdam 3015 GD, The Netherlands
| | | | - G Paul Legarda
- Sunshine Care Foundation, Roxas City, 5800 Capiz, Philippines
| | | | - Edwin L Muñoz
- Department of Pathology, College of Medicine, University of the Philippines, 1000 Manila, Philippines
| | - Mark A Ang
- Department of Pathology, College of Medicine, University of the Philippines, 1000 Manila, Philippines
| | - Cid Czarina E Diesta
- Department of Neurosciences, Makati Medical Center, 1229 Makati City, Philippines
| | - Menno P Creyghton
- Erasmus University Medical Center, Department of Developmental Biology, Rotterdam 3015 GD, The Netherlands
| | - Christine Klein
- Institute of Neurogenetics and Department of Neurology, University of Lübeck, 23538 Lübeck, Germany
| | - D Cristopher Bragg
- The Collaborative Center for X-Linked Dystonia Parkinsonism (CCXDP), Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Peter De Rijk
- Neuromics Support Facility, VIB Center for Molecular Neurology, VIB - University of Antwerp, B-2610 Antwerp, Belgium
| | - H T Marc Timmers
- German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center (DKFZ), Department of Urology, Medical Center-University of Freiburg, 79106 Freiburg, Germany
| |
Collapse
|