title: Galectin-8 promotes cytoskeletal rearrangement in trabecular meshwork cells through activation of Rho signaling.
abstract: OBJECTIVE
  The trabecular meshwork (TM) cell-matrix interactions and factors that influence Rho signaling in TM cells are thought to play a pivotal role in the regulation of aqueous outflow. The current study was designed to evaluate the role of a carbohydrate-binding protein, galectin-8 (Gal8), in TM cell adhesion and Rho signaling.
  
  
  METHODS
  Normal human TM cells were assayed for Gal8 expression by immunohistochemistry and Western blot analysis. To assess the role of Gal8 in TM cell adhesion and Rho signaling, the cell adhesion and spreading assays were performed on Gal8-coated culture plates in the presence and the absence of anti-β₁ integrin antibody and Rho and Rho-kinase inhibitors. In addition, the effect of Gal8-mediated cell-matrix interactions on TM cell cytoskeleton arrangement and myosin light chain 2 (MLC2) phosphorylation was examined.
  
  
  RESULTS
  We demonstrate here that Gal8 is expressed in the TM and a function-blocking anti-β₁ integrin antibody inhibits the adhesion and spreading of TM cells to Gal8-coated wells. Cell spreading on Gal8 substratum was associated with the accumulation of phosphorylated myosin light chain and the formation of stress fibers that was inhibited by the Rho inhibitor, C3 transferase, as well as by the Rho-kinase inhibitor, Y27632.
  
  
  CONCLUSIONS
  The above findings present a novel function for Gal8 in activating Rho signaling in TM cells. This function may allow Gal8 to participate in the regulation of aqueous outflow.
authors.affiliation: Program in Cell, Molecular & Developmental Biology, Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, Massachusetts, United States of America.
authors.forename: Shiri
authors.initials: S
authors.lastname: Diskin
authors.forename: Wei-Sheng
authors.initials: WS
authors.lastname: Chen
authors.forename: Zhiyi
authors.initials: Z
authors.lastname: Cao
authors.forename: Smita
authors.initials: S
authors.lastname: Gyawali
authors.forename: Haiyan
authors.initials: H
authors.lastname: Gong
authors.forename: Andrea
authors.initials: A
authors.lastname: Soza
authors.forename: Alfonso
authors.initials: A
authors.lastname: González
authors.forename: Noorjahan
authors.initials: N
authors.lastname: Panjwani
mesh_terms: D015153:Blotting, Western; D024722:Cardiac Myosins / Q000378:metabolism; D002448:Cell Adhesion / Q000502:physiology; D002478:Cells, Cultured; D003599:Cytoskeleton / Q000235:genetics / Q000502:physiology*; D017931:DNA Primers / Q000235:genetics; D037161:Galectins / Q000378:metabolism*; D005982:Glutathione Transferase / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D019012:Integrin beta1 / Q000378:metabolism; D018994:Myosin Light Chains / Q000378:metabolism; D010766:Phosphorylation; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000235:genetics*; D014129:Trabecular Meshwork / Q000166:cytology*; D020741:rho GTP-Binding Proteins / Q000378:metabolism*; D054460:rho-Associated Kinases / Q000378:metabolism
chemical_list: D017931:DNA Primers; D037161:Galectins; D019012:Integrin beta1; C091991:LGALS8 protein, human; D018994:Myosin Light Chains; C107184:myosin light chain 2; D005982:Glutathione Transferase; D054460:rho-Associated Kinases; D024722:Cardiac Myosins; D020741:rho GTP-Binding Proteins