LIMCH1 regulates nonmuscle myosin-II activity and suppresses cell migration

Mol Biol Cell. 2017 Apr 15;28(8):1054-1065. doi: 10.1091/mbc.E15-04-0218. Epub 2017 Feb 22.


Nonmuscle myosin II (NM-II) is an important motor protein involved in cell migration. Incorporation of NM-II into actin stress fiber provides a traction force to promote actin retrograde flow and focal adhesion assembly. However, the components involved in regulation of NM-II activity are not well understood. Here we identified a novel actin stress fiber-associated protein, LIM and calponin-homology domains 1 (LIMCH1), which regulates NM-II activity. The recruitment of LIMCH1 into contractile stress fibers revealed its localization complementary to actinin-1. LIMCH1 interacted with NM-IIA, but not NM-IIB, independent of the inhibition of myosin ATPase activity with blebbistatin. Moreover, the N-terminus of LIMCH1 binds to the head region of NM-IIA. Depletion of LIMCH1 attenuated myosin regulatory light chain (MRLC) diphosphorylation in HeLa cells, which was restored by reexpression of small interfering RNA-resistant LIMCH1. In addition, LIMCH1-depleted HeLa cells exhibited a decrease in the number of actin stress fibers and focal adhesions, leading to enhanced cell migration. Collectively, our data suggest that LIMCH1 plays a positive role in regulation of NM-II activity through effects on MRLC during cell migration.

MeSH terms

  • Actin Cytoskeleton / metabolism
  • Actinin / metabolism
  • Cell Adhesion / physiology
  • Cell Line, Tumor
  • Cell Movement / physiology*
  • Cytoskeleton / metabolism
  • Focal Adhesions / metabolism
  • HeLa Cells
  • Humans
  • LIM Domain Proteins / metabolism*
  • Myosin Light Chains / metabolism
  • Nonmuscle Myosin Type IIA / metabolism
  • Phosphorylation
  • Stress Fibers / metabolism
  • Stress Fibers / physiology


  • LIM Domain Proteins
  • LIMCH1 protein, human
  • Myosin Light Chains
  • Actinin
  • Nonmuscle Myosin Type IIA