Alba Vera-Zambrano, Mauro Lago-Docampo, Natalia Gallego, Juan Felipe Franco-Gonzalez, Daniel Morales-Cano, Alejandro Cruz-Utrilla, Marta Villegas-Esguevillas, Edgar Fernandez-Malave, Pilar Escribano-Subias, Jair Antonio-Tenorio-Castano, Francisco Perez-Vizcaino, Diana Valverde, Teresa Gonzalez, Angel Cogolludo
Universidad Complutense de Madrid Facultad de Medicina. Universidad Autonoma de Madrid Facultad de Medicina. Instituto de Investigaciones Biomedicas Alberto Sols. Universidad de Vigo. Galicia Sur Health Research Institute. Hospital Universitario La Paz. Instituto de Salud Carlos III. European Reference Network on Rare Congenital Malformations and Rare Intellectual Disability. Margarita Salas Center for Biological Research. Centro Nacional de Investigaciones Cardiovasculares. Aarhus University. Instituto de Investigación Sanitaria Gregorio Marañón. Hospital Universitario 12 de Octubre.
Spain, Belgium and Denmark
American Journal of Cell and Molecular Biology
Am J Cell Mol Biol 2023;
DOI: 10.1165/rcmb.2022-0245OC
Abstract
Reduced expression and/or activity of Kv1.5 channels (encoded by KCNA5) is a common hallmark in human or experimental pulmonary arterial hypertension (PAH). Likewise, genetic variants in KCNA5 have been found in PAH patients, but their functional consequences and potential impact on the disease are largely unknown. Herein, we aimed to characterize the functional consequences of 7 KCNA5 variants found in a cohort of PAH patients. Potassium currents were recorded by patch-clamp technique in HEK293 cells transfected with WT or mutant Kv1.5 cDNA. Flow cytometry, western blot and confocal microscopy techniques were used for measuring protein expression and cell apoptosis in HEK293 and human pulmonary artery smooth muscle cells (hPASMC). KCNA5 variants found in PAH patients (namely, p.Arg184Pro and p.Gly384Arg) resulted in a clear loss of potassium channel function as assessed by electrophysiological and molecular modelling analyses. The p.Arg184Pro variant also resulted in a pronounced reduction of Kv1.5 expression. Transfection with p.Arg184Pro or p.Gly384Arg variants decreased apoptosis of hPASMCs compared with the WT, demonstrating that KCNA5 dysfunction in both variants affects cell viability. Thus, in addition to affecting channel activity, both variants were associated with impaired apoptosis, a crucial process linked to the disease. The estimated prevalence of dysfunctional KCNA5 variants in the PAH population analyzed was around 1 %. Our data indicate that some KCNA5 variants found PAH patients have critical consequences for channel function supporting the idea that KCNA5 pathogenic variants may be a causative or contributing factor for PAH.
Category
Genetic Factors Associated with Pulmonary Vascular Disease
Vascular Cell Biology and Mechanisms of Pulmonary Vascular Disease
Age Focus: No Age-Related Focus
Fresh or Filed Publication: Filed (PHiled). Greater than 1-2 years since publication
Article Access
Free PDF File or Full Text Article Available Through PubMed or DOI: No