Regulation of NaV1.5 Sodium Channels by Small G-Proteins of the Rho Family in a Heterologous Expression System

D V Abramochkin; K B Pustovit; A S Bilichenko; A Yu Khushkina; A V Karpushev

doi:10.1007/s10517-020-04966-8

Regulation of Na_V1.5 Sodium Channels by Small G-Proteins of the Rho Family in a Heterologous Expression System

Bull Exp Biol Med. 2020 Oct;169(6):729-733. doi: 10.1007/s10517-020-04966-8. Epub 2020 Oct 24.

Authors

D V Abramochkin^{1

2}, K B Pustovit^{3

4}, A S Bilichenko⁴, A Yu Khushkina⁵, A V Karpushev⁵

Affiliations

¹ Department of Human and Animal Physiology, M. V. Lomonosov Moscow State University, Moscow, Russia. abram340@mail.ru.
² Research Laboratory of Electrophysiology, N. I. Pirogov Russian National Research Medical University, Ministry of Health of the Russian Federation, Moscow, Russia. abram340@mail.ru.
³ Department of Human and Animal Physiology, M. V. Lomonosov Moscow State University, Moscow, Russia.
⁴ Research Laboratory of Electrophysiology, N. I. Pirogov Russian National Research Medical University, Ministry of Health of the Russian Federation, Moscow, Russia.
⁵ V. A. Almazov National Medical Research Center, Ministry of Health of the Russian Federation, St. Petersburg, Russia.

PMID: 33098508
DOI: 10.1007/s10517-020-04966-8

Abstract

The effect of small G-proteins of the Rho family on sodium current conducted by cardiac isoform Na_V1.5 of voltage-gated sodium channels was studied in heterologous expression system, CHO-K1 cell line transfected with a plasmid containing the Na_V1.5 gene. The influence of cotransfection with genes of wild-type, constitutively-active, and dominant-negative small G-proteins RhoA, Rac1, and Cdc2 on the parameters of sodium current and its noninactivating component (I_Na,late) was estimated. Among three studied small G-proteins, only RhoA (wild-type and constitutively-active type) strongly affected sodium current reducing its peak amplitude, but not the value of I_Na,late. Cotransfection with wild-type Rac1 resulted in a minor decrease in sodium current. Thus, small G-protein RhoA has potential capability for suppression of sodium current, although physiological relevance of this property has to be verified.

Keywords: ionic currents; myocardium; patch-clamp; small G-proteins; sodium channels.

MeSH terms

Animals
CHO Cells
Cnidarian Venoms / pharmacology
Cricetulus
Gene Expression Regulation*
Genes, Reporter
Green Fluorescent Proteins / genetics
Green Fluorescent Proteins / metabolism
Humans
Membrane Potentials / drug effects
Membrane Potentials / physiology*
NAV1.5 Voltage-Gated Sodium Channel / genetics*
NAV1.5 Voltage-Gated Sodium Channel / metabolism
Neurotoxins / pharmacology
Patch-Clamp Techniques
Plasmids / chemistry
Plasmids / metabolism
Transfection
Transgenes
cdc42 GTP-Binding Protein / genetics*
cdc42 GTP-Binding Protein / metabolism
rac1 GTP-Binding Protein / genetics*
rac1 GTP-Binding Protein / metabolism
rhoA GTP-Binding Protein / genetics*
rhoA GTP-Binding Protein / metabolism

Substances

Cnidarian Venoms
NAV1.5 Voltage-Gated Sodium Channel
Neurotoxins
RAC1 protein, human
SCN5A protein, human
RHOA protein, human
Green Fluorescent Proteins
toxin II (Anemonia sulcata)
CDC42 protein, human
cdc42 GTP-Binding Protein
rac1 GTP-Binding Protein
rhoA GTP-Binding Protein