Functional Consequences of the <i>SCN5A</i>-p.Y1977N Mutation within the PY Ubiquitylation Motif: Discrepancy between HEK293 Cells and Transgenic Mice
Dysfunction of the cardiac sodium channel Nav1.5 (encoded by the <i>SCN5A</i> gene) is associated with arrhythmias and sudden cardiac death. <i>SCN5A</i> mutations associated with long QT syndrome type 3 (LQT3) lead to enhanced late sodium current and consequent action potent...
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| Format: | Article |
| Language: | English |
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MDPI AG
2019-10-01
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| Series: | International Journal of Molecular Sciences |
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| Online Access: | https://www.mdpi.com/1422-0067/20/20/5033 |
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doaj-303d9d696c274f688ffc404464157d77 |
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| record_format |
Article |
| collection |
DOAJ |
| language |
English |
| format |
Article |
| sources |
DOAJ |
| author |
Simona Casini Maxime Albesa Zizun Wang Vincent Portero Daniela Ross-Kaschitza Jean-Sébastien Rougier Gerard A. Marchal Wendy K. Chung Connie R. Bezzina Hugues Abriel Carol Ann Remme |
| spellingShingle |
Simona Casini Maxime Albesa Zizun Wang Vincent Portero Daniela Ross-Kaschitza Jean-Sébastien Rougier Gerard A. Marchal Wendy K. Chung Connie R. Bezzina Hugues Abriel Carol Ann Remme Functional Consequences of the <i>SCN5A</i>-p.Y1977N Mutation within the PY Ubiquitylation Motif: Discrepancy between HEK293 Cells and Transgenic Mice International Journal of Molecular Sciences <i>scn5a</i> ubiquitylation long qt syndrome sodium current nedd4-2 action potential patch-clamp mouse model |
| author_facet |
Simona Casini Maxime Albesa Zizun Wang Vincent Portero Daniela Ross-Kaschitza Jean-Sébastien Rougier Gerard A. Marchal Wendy K. Chung Connie R. Bezzina Hugues Abriel Carol Ann Remme |
| author_sort |
Simona Casini |
| title |
Functional Consequences of the <i>SCN5A</i>-p.Y1977N Mutation within the PY Ubiquitylation Motif: Discrepancy between HEK293 Cells and Transgenic Mice |
| title_short |
Functional Consequences of the <i>SCN5A</i>-p.Y1977N Mutation within the PY Ubiquitylation Motif: Discrepancy between HEK293 Cells and Transgenic Mice |
| title_full |
Functional Consequences of the <i>SCN5A</i>-p.Y1977N Mutation within the PY Ubiquitylation Motif: Discrepancy between HEK293 Cells and Transgenic Mice |
| title_fullStr |
Functional Consequences of the <i>SCN5A</i>-p.Y1977N Mutation within the PY Ubiquitylation Motif: Discrepancy between HEK293 Cells and Transgenic Mice |
| title_full_unstemmed |
Functional Consequences of the <i>SCN5A</i>-p.Y1977N Mutation within the PY Ubiquitylation Motif: Discrepancy between HEK293 Cells and Transgenic Mice |
| title_sort |
functional consequences of the <i>scn5a</i>-p.y1977n mutation within the py ubiquitylation motif: discrepancy between hek293 cells and transgenic mice |
| publisher |
MDPI AG |
| series |
International Journal of Molecular Sciences |
| issn |
1422-0067 |
| publishDate |
2019-10-01 |
| description |
Dysfunction of the cardiac sodium channel Nav1.5 (encoded by the <i>SCN5A</i> gene) is associated with arrhythmias and sudden cardiac death. <i>SCN5A</i> mutations associated with long QT syndrome type 3 (LQT3) lead to enhanced late sodium current and consequent action potential (AP) prolongation. Internalization and degradation of Na<sub>v</sub>1.5 is regulated by ubiquitylation, a post-translational mechanism that involves binding of the ubiquitin ligase Nedd4-2 to a proline-proline-serine-tyrosine sequence of Na<sub>v</sub>1.5, designated the PY-motif. We investigated the biophysical properties of the LQT3-associated <i>SCN5A</i>-p.Y1977N mutation located in the Na<sub>v</sub>1.5 PY-motif, both in HEK293 cells as well as in newly generated mice harboring the mouse homolog mutation <i>Scn5a</i>-p.Y1981N. We found that in HEK293 cells, the <i>SCN5A</i>-p.Y1977N mutation abolished the interaction between Na<sub>v</sub>1.5 and Nedd4-2, suppressed PY-motif-dependent ubiquitylation of Na<sub>v</sub>1.5, and consequently abrogated Nedd4-2 induced sodium current (I<sub>Na</sub>) decrease. Nevertheless, homozygous mice harboring the <i>Scn5a</i>-p.Y1981N mutation showed no electrophysiological alterations nor changes in AP or (late) I<sub>Na</sub> properties, questioning the in vivo relevance of the PY-motif. Our findings suggest the presence of compensatory mechanisms, with additional, as yet unknown, factors likely required to reduce the “ubiquitylation reserve” of Na<sub>v</sub>1.5. Future identification of such modulatory factors may identify potential triggers for arrhythmias and sudden cardiac death in the setting of LQT3 mutations. |
| topic |
<i>scn5a</i> ubiquitylation long qt syndrome sodium current nedd4-2 action potential patch-clamp mouse model |
| url |
https://www.mdpi.com/1422-0067/20/20/5033 |
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doaj-303d9d696c274f688ffc404464157d772020-11-25T01:11:53ZengMDPI AGInternational Journal of Molecular Sciences1422-00672019-10-012020503310.3390/ijms20205033ijms20205033Functional Consequences of the <i>SCN5A</i>-p.Y1977N Mutation within the PY Ubiquitylation Motif: Discrepancy between HEK293 Cells and Transgenic MiceSimona Casini0Maxime Albesa1Zizun Wang2Vincent Portero3Daniela Ross-Kaschitza4Jean-Sébastien Rougier5Gerard A. Marchal6Wendy K. Chung7Connie R. Bezzina8Hugues Abriel9Carol Ann Remme10Department of Clinical and Experimental Cardiology, Heart Centre, Amsterdam UMC, Location Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 Amsterdam, The NetherlandsIon Channels and Channelopathies Laboratory, Institute for Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, SwitzerlandIon Channels and Channelopathies Laboratory, Institute for Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, SwitzerlandDepartment of Clinical and Experimental Cardiology, Heart Centre, Amsterdam UMC, Location Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 Amsterdam, The NetherlandsIon Channels and Channelopathies Laboratory, Institute for Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, SwitzerlandIon Channels and Channelopathies Laboratory, Institute for Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, SwitzerlandDepartment of Clinical and Experimental Cardiology, Heart Centre, Amsterdam UMC, Location Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 Amsterdam, The NetherlandsDepartments of Pediatrics & Medicine, Columbia University Medical Center, 1150 St Nicholas Avenue, New York, NY 10032, USADepartment of Clinical and Experimental Cardiology, Heart Centre, Amsterdam UMC, Location Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 Amsterdam, The NetherlandsIon Channels and Channelopathies Laboratory, Institute for Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, SwitzerlandDepartment of Clinical and Experimental Cardiology, Heart Centre, Amsterdam UMC, Location Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 Amsterdam, The NetherlandsDysfunction of the cardiac sodium channel Nav1.5 (encoded by the <i>SCN5A</i> gene) is associated with arrhythmias and sudden cardiac death. <i>SCN5A</i> mutations associated with long QT syndrome type 3 (LQT3) lead to enhanced late sodium current and consequent action potential (AP) prolongation. Internalization and degradation of Na<sub>v</sub>1.5 is regulated by ubiquitylation, a post-translational mechanism that involves binding of the ubiquitin ligase Nedd4-2 to a proline-proline-serine-tyrosine sequence of Na<sub>v</sub>1.5, designated the PY-motif. We investigated the biophysical properties of the LQT3-associated <i>SCN5A</i>-p.Y1977N mutation located in the Na<sub>v</sub>1.5 PY-motif, both in HEK293 cells as well as in newly generated mice harboring the mouse homolog mutation <i>Scn5a</i>-p.Y1981N. We found that in HEK293 cells, the <i>SCN5A</i>-p.Y1977N mutation abolished the interaction between Na<sub>v</sub>1.5 and Nedd4-2, suppressed PY-motif-dependent ubiquitylation of Na<sub>v</sub>1.5, and consequently abrogated Nedd4-2 induced sodium current (I<sub>Na</sub>) decrease. Nevertheless, homozygous mice harboring the <i>Scn5a</i>-p.Y1981N mutation showed no electrophysiological alterations nor changes in AP or (late) I<sub>Na</sub> properties, questioning the in vivo relevance of the PY-motif. Our findings suggest the presence of compensatory mechanisms, with additional, as yet unknown, factors likely required to reduce the “ubiquitylation reserve” of Na<sub>v</sub>1.5. Future identification of such modulatory factors may identify potential triggers for arrhythmias and sudden cardiac death in the setting of LQT3 mutations.https://www.mdpi.com/1422-0067/20/20/5033<i>scn5a</i>ubiquitylationlong qt syndromesodium currentnedd4-2action potentialpatch-clampmouse model |