Asymmetric Distribution of Myosin IIB in Migrating Endothelial Cells Is Regulated by a rho-dependent Kinase and Contributes to Tail Retraction
AUTOR(ES)
Kolega, John
FONTE
The American Society for Cell Biology
RESUMO
All vertebrates contain two nonmuscle myosin II heavy chains, A and B, which differ in tissue expression and subcellular distributions. To understand how these distinct distributions are controlled and what role they play in cell migration, myosin IIA and IIB were examined during wound healing by bovine aortic endothelial cells. Immunofluorescence showed that myosin IIA skewed toward the front of migrating cells, coincident with actin assembly at the leading edge, whereas myosin IIB accumulated in the rear 15–30 min later. Inhibition of myosin light-chain kinase, protein kinases A, C, and G, tyrosine kinase, MAP kinase, and PIP3 kinase did not affect this asymmetric redistribution of myosin isoforms. However, posterior accumulation of myosin IIB, but not anterior distribution of myosin IIA, was inhibited by dominant-negative rhoA and by the rho-kinase inhibitor, Y-27632, which also inhibited myosin light-chain phosphorylation. This inhibition was overcome by transfecting cells with constitutively active myosin light-chain kinase. These observations indicate that asymmetry of myosin IIB, but not IIA, is regulated by light-chain phosphorylation mediated by rho-dependent kinase. Blocking this pathway inhibited tail constriction and retraction, but did not affect protrusion, suggesting that myosin IIB functions in pulling the rear of the cell forward.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=284780Documentos Relacionados
- Citron Kinase, a Rho-dependent Kinase, Induces Di-phosphorylation of Regulatory Light Chain of Myosin II
- Activation of integrins in endothelial cells by fluid shear stress mediates Rho-dependent cytoskeletal alignment
- Rho-dependent formation of epithelial “leader” cells during wound healing
- Rho-dependent membrane folding causes Shigella entry into epithelial cells.
- Sphingosine-1-phosphate rapidly induces Rho-dependent neurite retraction: action through a specific cell surface receptor.
