Nonmuscle myosin II isoforms interact with sodium channel alpha subunits

Mol Pain. 2018 Jan-Dec:14:1744806918788638. doi: 10.1177/1744806918788638. Epub 2018 Jun 29.


Sodium channels play pivotal roles in health and diseases due to their ability to control cellular excitability. The pore-forming α-subunits (sodium channel alpha subunits) of the voltage-sensitive channels (i.e., Nav1.1-1.9) and the nonvoltage-dependent channel (i.e., Nax) share a common structural motif and selectivity for sodium ions. We hypothesized that the actin-based nonmuscle myosin II motor proteins, nonmuscle myosin heavy chain-IIA/myh9, and nonmuscle myosin heavy chain-IIB/myh10 might interact with sodium channel alpha subunits to play an important role in their transport, trafficking, and/or function. Immunochemical and electrophysiological assays were conducted using rodent nervous (brain and dorsal root ganglia) tissues and ND7/23 cells coexpressing Nav subunits and recombinant myosins. Immunoprecipitation of myh9 and myh10 from rodent brain tissues led to the coimmunoprecipitation of Nax, Nav1.2, and Nav1.3 subunits, but not Nav1.1 and Nav1.6 subunits, expressed there. Similarly, immunoprecipitation of myh9 and myh10 from rodent dorsal root ganglia tissues led to the coimmunoprecipitation of Nav1.7 and Nav1.8 subunits, but not Nav1.9 subunits, expressed there. The functional implication of one of these interactions was assessed by coexpressing myh10 along with Nav1.8 subunits in ND7/23 cells. Myh10 overexpression led to three-fold increase ( P < 0.01) in the current density of Nav1.8 channels expressed in ND7/23 cells. Myh10 coexpression also hyperpolarized voltage-dependent activation and steady-state fast inactivation of Nav1.8 channels. In addition, coexpression of myh10 reduced ( P < 0.01) the offset of fast inactivation and the amplitude of the ramp currents of Nav1.8 channels. These results indicate that nonmuscle myosin heavy chain-IIs interact with sodium channel alpha subunits subunits in an isoform-dependent manner and influence their functional properties.

Keywords: Myosins; myh10; myh9; nonmuscle myosin heavy chains; sodium channel; voltage clamp.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Action Potentials / drug effects
  • Action Potentials / genetics
  • Animals
  • Ankyrins / metabolism
  • Brain / metabolism
  • Cell Line, Transformed
  • Electric Stimulation
  • Ganglia, Spinal / metabolism
  • Gene Expression Regulation
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / metabolism
  • Humans
  • Immunoprecipitation
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Molecular Motor Proteins / metabolism
  • Myosin Heavy Chains / genetics
  • Myosin Heavy Chains / metabolism*
  • NAV1.6 Voltage-Gated Sodium Channel / genetics
  • NAV1.6 Voltage-Gated Sodium Channel / metabolism*
  • Nonmuscle Myosin Type IIB / genetics
  • Nonmuscle Myosin Type IIB / metabolism*
  • Patch-Clamp Techniques
  • Rats
  • Transfection


  • Ankyrins
  • MYH9 protein, human
  • Molecular Motor Proteins
  • NAV1.6 Voltage-Gated Sodium Channel
  • SCN8A protein, human
  • Green Fluorescent Proteins
  • Nonmuscle Myosin Type IIB
  • nonmuscle myosin type IIB heavy chain
  • Myosin Heavy Chains