title: Actin-myosin contractility is responsible for the reduced viability of dissociated human embryonic stem cells.
abstract: Human ESCs are the pluripotent precursor of the three embryonic germ layers. Human ESCs exhibit basal-apical polarity, junctional complexes, integrin-dependent matrix adhesion, and E-cadherin-dependent cell-cell adhesion, all characteristics shared by the epiblast epithelium of the intact mammalian embryo. After disruption of epithelial structures, programmed cell death is commonly observed. If individualized human ESCs are prevented from reattaching and forming colonies, their viability is significantly reduced. Here, we show that actin-myosin contraction is a critical effector of the cell death response to human ESC dissociation. Inhibition of myosin heavy chain ATPase, downregulation of myosin heavy chain, and downregulation of myosin light chain all increase survival and cloning efficiency of individualized human ESCs. ROCK inhibition decreases phosphorylation of myosin light chain, suggesting that inhibition of actin-myosin contraction is also the mechanism through which ROCK inhibitors increase cloning efficiency of human ESCs.
authors.affiliation: Morgridge Institute for Research, Madison, WI 53707-7365, USA.
authors.forename: Guokai
authors.initials: G
authors.lastname: Chen
authors.forename: Zhonggang
authors.initials: Z
authors.lastname: Hou
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Gulbranson
authors.forename: James A
authors.initials: JA
authors.lastname: Thomson
mesh_terms: D008841:Actin Cytoskeleton / Q000187:drug effects / Q000378:metabolism; D000199:Actins / Q000378:metabolism*; D002450:Cell Communication / Q000187:drug effects; D016923:Cell Death / Q000187:drug effects; D022081:Cell Surface Extensions / Q000187:drug effects / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D002999:Clone Cells; D053595:Embryonic Stem Cells / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D055785:Gene Knockdown Techniques; D006576:Heterocyclic Compounds, 4 or More Rings / Q000494:pharmacology; D006801:Humans; D020409:Molecular Motor Proteins / Q000378:metabolism; D018995:Myosin Heavy Chains / Q000378:metabolism; D018994:Myosin Light Chains / Q000037:antagonists & inhibitors / Q000378:metabolism; D009218:Myosins / Q000378:metabolism*; D010766:Phosphorylation / Q000187:drug effects; D054460:rho-Associated Kinases / Q000378:metabolism
chemical_list: D000199:Actins; D006576:Heterocyclic Compounds, 4 or More Rings; C103814:MYH9 protein, human; D020409:Molecular Motor Proteins; D018994:Myosin Light Chains; C472645:blebbistatin; D054460:rho-Associated Kinases; D018995:Myosin Heavy Chains; D009218:Myosins