<i>KCNQ1</i> p.D446E Variant as a Risk Allele for Arrhythmogenic Phenotypes: Electrophysiological Characterization Reveals a Complex Phenotype Affecting the Slow Delayed Rectifier Potassium Current (IKs) Voltage Dependence by Causing a Hyperpolarizing Shift and a Lack of Response to Protein Kinase A Activation
Genetic testing is crucial in inherited arrhythmogenic channelopathies; however, the clinical interpretation of genetic variants remains challenging. Incomplete penetrance, oligogenic, polygenic or multifactorial forms of channelopathies further complicate variant interpretation. We identified the &...
| Main Authors: | , , , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2024-01-01
|
| Series: | International Journal of Molecular Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1422-0067/25/2/953 |
| _version_ | 1797339803039039488 |
|---|---|
| author | Antonia González-Garrido Omar López-Ramírez Abel Cerda-Mireles Thania Navarrete-Miranda Aranza Iztanami Flores-Arenas Arturo Rojo-Domínguez Leticia Arregui Pedro Iturralde Erika Antúnez-Argüelles Mayra Domínguez-Pérez Leonor Jacobo-Albavera Alessandra Carnevale Teresa Villarreal-Molina |
| author_facet | Antonia González-Garrido Omar López-Ramírez Abel Cerda-Mireles Thania Navarrete-Miranda Aranza Iztanami Flores-Arenas Arturo Rojo-Domínguez Leticia Arregui Pedro Iturralde Erika Antúnez-Argüelles Mayra Domínguez-Pérez Leonor Jacobo-Albavera Alessandra Carnevale Teresa Villarreal-Molina |
| author_sort | Antonia González-Garrido |
| collection | DOAJ |
| description | Genetic testing is crucial in inherited arrhythmogenic channelopathies; however, the clinical interpretation of genetic variants remains challenging. Incomplete penetrance, oligogenic, polygenic or multifactorial forms of channelopathies further complicate variant interpretation. We identified the <i>KCNQ1</i>/p.D446E variant in 2/63 patients with long QT syndrome, 30-fold more frequent than in public databases. We thus characterized the biophysical phenotypes of wildtype and mutant IKs co-expressing these alleles with the β-subunit minK in HEK293 cells. <i>KCNQ1</i> p.446E homozygosity significantly shifted IKs voltage dependence to hyperpolarizing potentials in basal conditions (gain of function) but failed to shift voltage dependence to hyperpolarizing potentials (loss of function) in the presence of 8Br-cAMP, a protein kinase A activator. Basal IKs activation kinetics did not differ among genotypes, but in response to 8Br-cAMP, IKs 446 E/E (homozygous) activation kinetics were slower at the most positive potentials. Protein modeling predicted a slower transition of the 446E Kv7.1 tetrameric channel to the stabilized open state. In conclusion, biophysical and modelling evidence shows that the <i>KCNQ1</i> p.D446E variant has complex functional consequences including both gain and loss of function, suggesting a contribution to the pathogenesis of arrhythmogenic phenotypes as a functional risk allele. |
| first_indexed | 2024-03-08T09:53:40Z |
| format | Article |
| id | doaj.art-3e7a9984090a43c4bc94d478f171984d |
| institution | Directory Open Access Journal |
| issn | 1661-6596 1422-0067 |
| language | English |
| last_indexed | 2024-03-08T09:53:40Z |
| publishDate | 2024-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | International Journal of Molecular Sciences |
| spelling | doaj.art-3e7a9984090a43c4bc94d478f171984d2024-01-29T13:55:47ZengMDPI AGInternational Journal of Molecular Sciences1661-65961422-00672024-01-0125295310.3390/ijms25020953<i>KCNQ1</i> p.D446E Variant as a Risk Allele for Arrhythmogenic Phenotypes: Electrophysiological Characterization Reveals a Complex Phenotype Affecting the Slow Delayed Rectifier Potassium Current (IKs) Voltage Dependence by Causing a Hyperpolarizing Shift and a Lack of Response to Protein Kinase A ActivationAntonia González-Garrido0Omar López-Ramírez1Abel Cerda-Mireles2Thania Navarrete-Miranda3Aranza Iztanami Flores-Arenas4Arturo Rojo-Domínguez5Leticia Arregui6Pedro Iturralde7Erika Antúnez-Argüelles8Mayra Domínguez-Pérez9Leonor Jacobo-Albavera10Alessandra Carnevale11Teresa Villarreal-Molina12Laboratorio de Enfermedades Mendelianas, Instituto Nacional de Medicina Genómica (INMEGEN), Mexico City 14610, MexicoInstituto de Oftalmología Fundación de Asistencia Privada Conde de la Valenciana, I.A.P., Mexico City 06800, MexicoLaboratorio de Enfermedades Mendelianas, Instituto Nacional de Medicina Genómica (INMEGEN), Mexico City 14610, MexicoLaboratorio de Enfermedades Mendelianas, Instituto Nacional de Medicina Genómica (INMEGEN), Mexico City 14610, MexicoLaboratorio de Enfermedades Mendelianas, Instituto Nacional de Medicina Genómica (INMEGEN), Mexico City 14610, MexicoDepartamento de Ciencias Naturales, Universidad Autónoma Metropolitana, Unidad Cuajimalpa, Mexico City 05348, MexicoDepartamento de Ciencias Naturales, Universidad Autónoma Metropolitana, Unidad Cuajimalpa, Mexico City 05348, MexicoDepartamento de Electrofisiología, Instituto Nacional de Cardiología “Ignacio Chávez”, Mexico City 14080, MexicoInstituto de Genética, Universidad del Mar, Campus Puerto Escondido, Oaxaca 70985, MexicoLaboratorio de Genómica de Enfermedades Cardiovasculares, Instituto Nacional de Medicina Genómica (INMEGEN), Mexico City 14610, MexicoLaboratorio de Genómica de Enfermedades Cardiovasculares, Instituto Nacional de Medicina Genómica (INMEGEN), Mexico City 14610, MexicoLaboratorio de Enfermedades Mendelianas, Instituto Nacional de Medicina Genómica (INMEGEN), Mexico City 14610, MexicoLaboratorio de Genómica de Enfermedades Cardiovasculares, Instituto Nacional de Medicina Genómica (INMEGEN), Mexico City 14610, MexicoGenetic testing is crucial in inherited arrhythmogenic channelopathies; however, the clinical interpretation of genetic variants remains challenging. Incomplete penetrance, oligogenic, polygenic or multifactorial forms of channelopathies further complicate variant interpretation. We identified the <i>KCNQ1</i>/p.D446E variant in 2/63 patients with long QT syndrome, 30-fold more frequent than in public databases. We thus characterized the biophysical phenotypes of wildtype and mutant IKs co-expressing these alleles with the β-subunit minK in HEK293 cells. <i>KCNQ1</i> p.446E homozygosity significantly shifted IKs voltage dependence to hyperpolarizing potentials in basal conditions (gain of function) but failed to shift voltage dependence to hyperpolarizing potentials (loss of function) in the presence of 8Br-cAMP, a protein kinase A activator. Basal IKs activation kinetics did not differ among genotypes, but in response to 8Br-cAMP, IKs 446 E/E (homozygous) activation kinetics were slower at the most positive potentials. Protein modeling predicted a slower transition of the 446E Kv7.1 tetrameric channel to the stabilized open state. In conclusion, biophysical and modelling evidence shows that the <i>KCNQ1</i> p.D446E variant has complex functional consequences including both gain and loss of function, suggesting a contribution to the pathogenesis of arrhythmogenic phenotypes as a functional risk allele.https://www.mdpi.com/1422-0067/25/2/953<i>KCNQ1</i>p.D446Elow-frequency polymorphismlong QT syndromeearly repolarizationloss of function |
| spellingShingle | Antonia González-Garrido Omar López-Ramírez Abel Cerda-Mireles Thania Navarrete-Miranda Aranza Iztanami Flores-Arenas Arturo Rojo-Domínguez Leticia Arregui Pedro Iturralde Erika Antúnez-Argüelles Mayra Domínguez-Pérez Leonor Jacobo-Albavera Alessandra Carnevale Teresa Villarreal-Molina <i>KCNQ1</i> p.D446E Variant as a Risk Allele for Arrhythmogenic Phenotypes: Electrophysiological Characterization Reveals a Complex Phenotype Affecting the Slow Delayed Rectifier Potassium Current (IKs) Voltage Dependence by Causing a Hyperpolarizing Shift and a Lack of Response to Protein Kinase A Activation International Journal of Molecular Sciences <i>KCNQ1</i> p.D446E low-frequency polymorphism long QT syndrome early repolarization loss of function |
| title | <i>KCNQ1</i> p.D446E Variant as a Risk Allele for Arrhythmogenic Phenotypes: Electrophysiological Characterization Reveals a Complex Phenotype Affecting the Slow Delayed Rectifier Potassium Current (IKs) Voltage Dependence by Causing a Hyperpolarizing Shift and a Lack of Response to Protein Kinase A Activation |
| title_full | <i>KCNQ1</i> p.D446E Variant as a Risk Allele for Arrhythmogenic Phenotypes: Electrophysiological Characterization Reveals a Complex Phenotype Affecting the Slow Delayed Rectifier Potassium Current (IKs) Voltage Dependence by Causing a Hyperpolarizing Shift and a Lack of Response to Protein Kinase A Activation |
| title_fullStr | <i>KCNQ1</i> p.D446E Variant as a Risk Allele for Arrhythmogenic Phenotypes: Electrophysiological Characterization Reveals a Complex Phenotype Affecting the Slow Delayed Rectifier Potassium Current (IKs) Voltage Dependence by Causing a Hyperpolarizing Shift and a Lack of Response to Protein Kinase A Activation |
| title_full_unstemmed | <i>KCNQ1</i> p.D446E Variant as a Risk Allele for Arrhythmogenic Phenotypes: Electrophysiological Characterization Reveals a Complex Phenotype Affecting the Slow Delayed Rectifier Potassium Current (IKs) Voltage Dependence by Causing a Hyperpolarizing Shift and a Lack of Response to Protein Kinase A Activation |
| title_short | <i>KCNQ1</i> p.D446E Variant as a Risk Allele for Arrhythmogenic Phenotypes: Electrophysiological Characterization Reveals a Complex Phenotype Affecting the Slow Delayed Rectifier Potassium Current (IKs) Voltage Dependence by Causing a Hyperpolarizing Shift and a Lack of Response to Protein Kinase A Activation |
| title_sort | i kcnq1 i p d446e variant as a risk allele for arrhythmogenic phenotypes electrophysiological characterization reveals a complex phenotype affecting the slow delayed rectifier potassium current iks voltage dependence by causing a hyperpolarizing shift and a lack of response to protein kinase a activation |
| topic | <i>KCNQ1</i> p.D446E low-frequency polymorphism long QT syndrome early repolarization loss of function |
| url | https://www.mdpi.com/1422-0067/25/2/953 |
| work_keys_str_mv | AT antoniagonzalezgarrido ikcnq1ipd446evariantasariskalleleforarrhythmogenicphenotypeselectrophysiologicalcharacterizationrevealsacomplexphenotypeaffectingtheslowdelayedrectifierpotassiumcurrentiksvoltagedependencebycausingahyperpolarizingshiftandalackofresponsetoproteinkinaseaact AT omarlopezramirez ikcnq1ipd446evariantasariskalleleforarrhythmogenicphenotypeselectrophysiologicalcharacterizationrevealsacomplexphenotypeaffectingtheslowdelayedrectifierpotassiumcurrentiksvoltagedependencebycausingahyperpolarizingshiftandalackofresponsetoproteinkinaseaact AT abelcerdamireles ikcnq1ipd446evariantasariskalleleforarrhythmogenicphenotypeselectrophysiologicalcharacterizationrevealsacomplexphenotypeaffectingtheslowdelayedrectifierpotassiumcurrentiksvoltagedependencebycausingahyperpolarizingshiftandalackofresponsetoproteinkinaseaact AT thanianavarretemiranda ikcnq1ipd446evariantasariskalleleforarrhythmogenicphenotypeselectrophysiologicalcharacterizationrevealsacomplexphenotypeaffectingtheslowdelayedrectifierpotassiumcurrentiksvoltagedependencebycausingahyperpolarizingshiftandalackofresponsetoproteinkinaseaact AT aranzaiztanamifloresarenas ikcnq1ipd446evariantasariskalleleforarrhythmogenicphenotypeselectrophysiologicalcharacterizationrevealsacomplexphenotypeaffectingtheslowdelayedrectifierpotassiumcurrentiksvoltagedependencebycausingahyperpolarizingshiftandalackofresponsetoproteinkinaseaact AT arturorojodominguez ikcnq1ipd446evariantasariskalleleforarrhythmogenicphenotypeselectrophysiologicalcharacterizationrevealsacomplexphenotypeaffectingtheslowdelayedrectifierpotassiumcurrentiksvoltagedependencebycausingahyperpolarizingshiftandalackofresponsetoproteinkinaseaact AT leticiaarregui ikcnq1ipd446evariantasariskalleleforarrhythmogenicphenotypeselectrophysiologicalcharacterizationrevealsacomplexphenotypeaffectingtheslowdelayedrectifierpotassiumcurrentiksvoltagedependencebycausingahyperpolarizingshiftandalackofresponsetoproteinkinaseaact AT pedroiturralde ikcnq1ipd446evariantasariskalleleforarrhythmogenicphenotypeselectrophysiologicalcharacterizationrevealsacomplexphenotypeaffectingtheslowdelayedrectifierpotassiumcurrentiksvoltagedependencebycausingahyperpolarizingshiftandalackofresponsetoproteinkinaseaact AT erikaantunezarguelles ikcnq1ipd446evariantasariskalleleforarrhythmogenicphenotypeselectrophysiologicalcharacterizationrevealsacomplexphenotypeaffectingtheslowdelayedrectifierpotassiumcurrentiksvoltagedependencebycausingahyperpolarizingshiftandalackofresponsetoproteinkinaseaact AT mayradominguezperez ikcnq1ipd446evariantasariskalleleforarrhythmogenicphenotypeselectrophysiologicalcharacterizationrevealsacomplexphenotypeaffectingtheslowdelayedrectifierpotassiumcurrentiksvoltagedependencebycausingahyperpolarizingshiftandalackofresponsetoproteinkinaseaact AT leonorjacoboalbavera ikcnq1ipd446evariantasariskalleleforarrhythmogenicphenotypeselectrophysiologicalcharacterizationrevealsacomplexphenotypeaffectingtheslowdelayedrectifierpotassiumcurrentiksvoltagedependencebycausingahyperpolarizingshiftandalackofresponsetoproteinkinaseaact AT alessandracarnevale ikcnq1ipd446evariantasariskalleleforarrhythmogenicphenotypeselectrophysiologicalcharacterizationrevealsacomplexphenotypeaffectingtheslowdelayedrectifierpotassiumcurrentiksvoltagedependencebycausingahyperpolarizingshiftandalackofresponsetoproteinkinaseaact AT teresavillarrealmolina ikcnq1ipd446evariantasariskalleleforarrhythmogenicphenotypeselectrophysiologicalcharacterizationrevealsacomplexphenotypeaffectingtheslowdelayedrectifierpotassiumcurrentiksvoltagedependencebycausingahyperpolarizingshiftandalackofresponsetoproteinkinaseaact |