C-terminal proline deletions in KCNC3 cause delayed channel inactivation and an adult-onset progressive SCA13 with spasticity.
Publication/Presentation Date
10-1-2018
Abstract
Mutations in the potassium channel gene KCNC3 (Kv3.3) cause the autosomal dominant neurological disease, spinocerebellar ataxia 13 (SCA13). In this study, we expand the genotype-phenotype repertoire of SCA13 by describing the novel KCNC3 deletion p.Pro583_Pro585del highlighting the allelic heterogeneity observed in SCA13 patients. We characterize adult-onset, progressive clinical symptoms of two afflicted kindred and introduce the symptom of profound spasticity not previously associated with the SCA13 phenotype. We also present molecular and electrophysiological characterizations of the mutant protein in mammalian cell culture. Mechanistically, the p.Pro583_Pro585del protein showed normal membrane trafficking with an altered electrophysiological profile, including slower inactivation and decreased sensitivity to the inactivation-accelerating effects of the actin depolymerizer latrunculin B. Taken together, our results highlight the clinical importance of the intracellular C-terminal portion of Kv3.3 and its association with ion channel function.
Volume
17
Issue
5
First Page
692
Last Page
697
ISSN
1473-4230
Published In/Presented At
Khare, S., Galeano, K., Zhang, Y., Nick, J. A., Nick, H. S., Subramony, S. H., Sampson, J., Kaczmarek, L. K., & Waters, M. F. (2018). C-terminal proline deletions in KCNC3 cause delayed channel inactivation and an adult-onset progressive SCA13 with spasticity. Cerebellum (London, England), 17(5), 692–697. https://doi.org/10.1007/s12311-018-0950-5
Disciplines
Medicine and Health Sciences
PubMedID
29949095
Department(s)
Department of Emergency Medicine, Department of Emergency Medicine Residents, Toxicology Division, Fellows and Residents
Document Type
Article