Nieves Gomez-Hurtado1, Nicole J Boczek1, Dmytro O Kryshtal1, Christopher N Johnson1, Jennifer Sun1, Florentin R Nitu1, Razvan L Cornea1, Walter J Chazin1, Melissa L Calvert1, David J Tester1, Michael J Ackerman2, Björn C Knollmann2. 1. From the Vanderbilt Center for Arrhythmia Research and Therapeutics (VanCART), Division of Clinical Pharmacology, Vanderbilt University School of Medicine, Nashville, TN (N.G.-H., D.O.K., B.C.K.); Department Molecular Pharmacology & Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory (N.J.B., M.L.C., D.J.T., M.J.A.), Department of Cardiovascular Diseases, Division of Heart Rhythm Services (M.J.A.), and Department of Pediatrics, Division of Pediatric Cardiology (M.J.A.), Mayo Clinic, Rochester, MN; Departments of Biochemistry and Chemistry & Center for Structural Biology, Vanderbilt University, Nashville, TN (C.N.J., J.S., W.J.C.); and Department of Biochemistry, Molecular Biology & Biophysics, University of Minnesota, Minneapolis, MN (F.R.N., R.L.C.). 2. From the Vanderbilt Center for Arrhythmia Research and Therapeutics (VanCART), Division of Clinical Pharmacology, Vanderbilt University School of Medicine, Nashville, TN (N.G.-H., D.O.K., B.C.K.); Department Molecular Pharmacology & Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory (N.J.B., M.L.C., D.J.T., M.J.A.), Department of Cardiovascular Diseases, Division of Heart Rhythm Services (M.J.A.), and Department of Pediatrics, Division of Pediatric Cardiology (M.J.A.), Mayo Clinic, Rochester, MN; Departments of Biochemistry and Chemistry & Center for Structural Biology, Vanderbilt University, Nashville, TN (C.N.J., J.S., W.J.C.); and Department of Biochemistry, Molecular Biology & Biophysics, University of Minnesota, Minneapolis, MN (F.R.N., R.L.C.). bjorn.knollmann@vanderbilt.edu ackerman.michael@mayo.edu.
Abstract
BACKGROUND: Calmodulin (CaM) mutations are associated with severe forms of long QT syndrome and catecholaminergic polymorphic ventricular tachycardia (CPVT). CaM mutations are found in 13% of genotype-negative long QT syndrome patients, but the prevalence of CaM mutations in genotype-negative CPVT patients is unknown. Here, we identify and characterize CaM mutations in 12 patients with genotype-negative but clinically diagnosed CPVT. METHODS AND RESULTS: We performed mutational analysis of CALM1, CALM2, and CALM3 gene-coding regions, in vitro measurement of CaM-Ca(2+) (Ca)-binding affinity, ryanodine receptor 2-CaM binding, Ca handling, L-type Ca current, and action potential duration. We identified a novel CaM mutation-A103V-in CALM3 in 1 of 12 patients (8%), a female who experienced episodes of exertion-induced syncope since age 10, had normal QT interval, and displayed ventricular ectopy during stress testing consistent with CPVT. A103V modestly lowered CaM Ca-binding affinity (3-fold reduction versus WT-CaM), but did not alter CaM binding to ryanodine receptor 2. In permeabilized cardiomyocytes, A103V-CaM (100 nmol/L) promoted spontaneous Ca wave and spark activity, a cellular phenotype of ryanodine receptor 2 activation. Even a 1:3 mixture of A103V-CaM:WT-CaM activated Ca waves, demonstrating functional dominance. Compared with long QT syndrome D96V-CaM, A103V-CaM had significantly less effects on L-type Ca current inactivation, did not alter action potential duration, and caused delayed afterdepolarizations and triggered beats in intact cardiomyocytes. CONCLUSIONS: We discovered a novel CPVT mutation in the CALM3 gene that shares functional characteristics with established CPVT-associated mutations in CALM1. A small proportion of A103V-CaM is sufficient to evoke arrhythmogenic Ca disturbances via ryanodine receptor 2 dysregulation, which explains the autosomal dominant inheritance.
BACKGROUND:Calmodulin (CaM) mutations are associated with severe forms of long QT syndrome and catecholaminergic polymorphic ventricular tachycardia (CPVT). CaM mutations are found in 13% of genotype-negative long QT syndromepatients, but the prevalence of CaM mutations in genotype-negative CPVT patients is unknown. Here, we identify and characterize CaM mutations in 12 patients with genotype-negative but clinically diagnosed CPVT. METHODS AND RESULTS: We performed mutational analysis of CALM1, CALM2, and CALM3 gene-coding regions, in vitro measurement of CaM-Ca(2+) (Ca)-binding affinity, ryanodine receptor 2-CaM binding, Ca handling, L-type Ca current, and action potential duration. We identified a novel CaM mutation-A103V-in CALM3 in 1 of 12 patients (8%), a female who experienced episodes of exertion-induced syncope since age 10, had normal QT interval, and displayed ventricular ectopy during stress testing consistent with CPVT. A103V modestly lowered CaM Ca-binding affinity (3-fold reduction versus WT-CaM), but did not alter CaM binding to ryanodine receptor 2. In permeabilized cardiomyocytes, A103V-CaM (100 nmol/L) promoted spontaneous Ca wave and spark activity, a cellular phenotype of ryanodine receptor 2 activation. Even a 1:3 mixture of A103V-CaM:WT-CaM activated Ca waves, demonstrating functional dominance. Compared with long QT syndromeD96V-CaM, A103V-CaM had significantly less effects on L-type Ca current inactivation, did not alter action potential duration, and caused delayed afterdepolarizations and triggered beats in intact cardiomyocytes. CONCLUSIONS: We discovered a novel CPVT mutation in the CALM3 gene that shares functional characteristics with established CPVT-associated mutations in CALM1. A small proportion of A103V-CaM is sufficient to evoke arrhythmogenic Ca disturbances via ryanodine receptor 2 dysregulation, which explains the autosomal dominant inheritance.
Authors: Björn C Knollmann; Nagesh Chopra; Thinn Hlaing; Brandy Akin; Tao Yang; Kristen Ettensohn; Barbara E C Knollmann; Kenneth D Horton; Neil J Weissman; Izabela Holinstat; Wei Zhang; Dan M Roden; Larry R Jones; Clara Franzini-Armstrong; Karl Pfeifer Journal: J Clin Invest Date: 2006-08-24 Impact factor: 14.808
Authors: Nicole J Boczek; Nieves Gomez-Hurtado; Dan Ye; Melissa L Calvert; David J Tester; Dmytro Kryshtal; Hyun Seok Hwang; Christopher N Johnson; Walter J Chazin; Christina G Loporcaro; Maully Shah; Andrew L Papez; Yung R Lau; Ronald Kanter; Bjorn C Knollmann; Michael J Ackerman Journal: Circ Cardiovasc Genet Date: 2016-03-11
Authors: Lia Crotti; Christopher N Johnson; Elisabeth Graf; Gaetano M De Ferrari; Bettina F Cuneo; Marc Ovadia; John Papagiannis; Michael D Feldkamp; Subodh G Rathi; Jennifer D Kunic; Matteo Pedrazzini; Thomas Wieland; Peter Lichtner; Britt-Maria Beckmann; Travis Clark; Christian Shaffer; D Woodrow Benson; Stefan Kääb; Thomas Meitinger; Tim M Strom; Walter J Chazin; Peter J Schwartz; Alfred L George Journal: Circulation Date: 2013-02-06 Impact factor: 29.690
Authors: Hiroshi Watanabe; Nagesh Chopra; Derek Laver; Hyun Seok Hwang; Sean S Davies; Daniel E Roach; Henry J Duff; Dan M Roden; Arthur A M Wilde; Björn C Knollmann Journal: Nat Med Date: 2009-03-29 Impact factor: 53.440
Authors: Razvan L Cornea; Florentin Nitu; Simon Gruber; Katherine Kohler; Michael Satzer; David D Thomas; Bradley R Fruen Journal: Proc Natl Acad Sci U S A Date: 2009-03-30 Impact factor: 11.205
Authors: Lia Crotti; Carla Spazzolini; David J Tester; Alice Ghidoni; Alban-Elouen Baruteau; Britt-Maria Beckmann; Elijah R Behr; Jeffrey S Bennett; Connie R Bezzina; Zahurul A Bhuiyan; Alpay Celiker; Marina Cerrone; Federica Dagradi; Gaetano M De Ferrari; Susan P Etheridge; Meena Fatah; Pablo Garcia-Pavia; Saleh Al-Ghamdi; Robert M Hamilton; Zuhair N Al-Hassnan; Minoru Horie; Juan Jimenez-Jaimez; Ronald J Kanter; Juan P Kaski; Maria-Christina Kotta; Najim Lahrouchi; Naomasa Makita; Gabrielle Norrish; Hans H Odland; Seiko Ohno; John Papagiannis; Gianfranco Parati; Nicole Sekarski; Kristian Tveten; Matteo Vatta; Gregory Webster; Arthur A M Wilde; Julianne Wojciak; Alfred L George; Michael J Ackerman; Peter J Schwartz Journal: Eur Heart J Date: 2019-09-14 Impact factor: 29.983
Authors: Kafa Walweel; Nieves Gomez-Hurtado; Ye Wint Oo; Nicole A Beard; Cris Dos Remedios; Christopher N Johnson; Walter J Chazin; Dirk F van Helden; Björn C Knollmann; Derek R Laver Journal: J Am Coll Cardiol Date: 2017-07-04 Impact factor: 24.094
Authors: Lisa M Wren; Juan Jiménez-Jáimez; Saleh Al-Ghamdi; Jumana Y Al-Aama; Amnah Bdeir; Zuhair N Al-Hassnan; Jyn L Kuan; Roger Y Foo; Franck Potet; Christopher N Johnson; Miriam C Aziz; Gemma L Carvill; Juan-Pablo Kaski; Lia Crotti; Francesca Perin; Lorenzo Monserrat; Paul W Burridge; Peter J Schwartz; Walter J Chazin; Zahurul A Bhuiyan; Alfred L George Journal: Circ Genom Precis Med Date: 2019-08-27
Authors: Kaiqian Wang; Christian Holt; Jocelyn Lu; Malene Brohus; Kamilla Taunsig Larsen; Michael Toft Overgaard; Reinhard Wimmer; Filip Van Petegem Journal: Proc Natl Acad Sci U S A Date: 2018-10-22 Impact factor: 11.205