@article{15264,
  abstract     = {Signaling by the B cell antigen receptor (BCR) initiates actin remodeling. The assembly of branched actin networks that are nucleated by the Arp2/3 complex exert outward force on the plasma membrane, allowing B cells to form membrane protrusions that can scan the surface of antigen-presenting cells (APCs). The resulting Arp2/3 complex-dependent actin retrograde flow promotes the centripetal movement and progressive coalescence of BCR microclusters, which amplifies BCR signaling. Glia maturation factor γ (GMFγ) is an actin disassembly-protein that releases Arp2/3 complex-nucleated actin filaments from actin networks. By doing so, GMFγ could either oppose the actions of the Arp2/3 complex or support Arp2/3 complex-nucleated actin polymerization by contributing to the recycling of actin monomers and Arp2/3 complexes. We now show that reducing the levels of GMFγ in human B cell lines via transfection with a specific siRNA impairs the ability of B cells to spread on antigen-coated surfaces, decreases the velocity of actin retrograde flow, diminishes the coalescence of BCR microclusters into a central cluster at the B cell-APC contact site, and decreases APC-induced BCR signaling. These effects of depleting GMFγ are similar to what occurs when the Arp2/3 complex is inhibited. This suggests that GMFγ cooperates with the Arp2/3 complex to support BCR-induced actin remodeling and amplify BCR signaling at the immune synapse.},
  author       = {Deretic, Nikola and Bolger-Munro, Madison and Choi, Kate and Abraham, Libin and Gold, Michael R.},
  issn         = {2296-634X},
  journal      = {Frontiers in Cell and Developmental Biology},
  keywords     = {Cell Biology, Developmental Biology},
  publisher    = {Frontiers Media},
  title        = {{The actin-disassembly protein glia maturation factor γ enhances actin remodeling and B cell antigen receptor signaling at the immune synapse}},
  doi          = {10.3389/fcell.2021.647063},
  volume       = {9},
  year         = {2021},
}