article published yes Nikola Deretic author Madison Bolger-Munro author 516F03FA-93A3-11EA-A7C5-D6BE3DDC885E0000-0002-8176-4824 Kate Choi author Libin Abraham author Michael R. Gold author CaHe department 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. https://research-explorer.ista.ac.at/download/15264/15291/2021_Frontiers_Deretic.pdf application/pdfno https://creativecommons.org/licenses/by/4.0/ Frontiers Media2021 eng Cell BiologyDevelopmental Biology 2296-634X 3433681810.3389/fcell.2021.647063 9 Deretic, N., Bolger-Munro, M., Choi, K., Abraham, L., &#38; Gold, M. R. (2021). The actin-disassembly protein glia maturation factor γ enhances actin remodeling and B cell antigen receptor signaling at the immune synapse. <i>Frontiers in Cell and Developmental Biology</i>. Frontiers Media. <a href="https://doi.org/10.3389/fcell.2021.647063">https://doi.org/10.3389/fcell.2021.647063</a> N. Deretic, M. Bolger-Munro, K. Choi, L. Abraham, M.R. Gold, Frontiers in Cell and Developmental Biology 9 (2021). N. Deretic, M. Bolger-Munro, K. Choi, L. Abraham, and M. R. Gold, “The actin-disassembly protein glia maturation factor γ enhances actin remodeling and B cell antigen receptor signaling at the immune synapse,” <i>Frontiers in Cell and Developmental Biology</i>, vol. 9. Frontiers Media, 2021. Deretic, Nikola, et al. “The Actin-Disassembly Protein Glia Maturation Factor γ Enhances Actin Remodeling and B Cell Antigen Receptor Signaling at the Immune Synapse.” <i>Frontiers in Cell and Developmental Biology</i>, vol. 9, 647063, Frontiers Media, 2021, doi:<a href="https://doi.org/10.3389/fcell.2021.647063">10.3389/fcell.2021.647063</a>. Deretic N, Bolger-Munro M, Choi K, Abraham L, Gold MR. 2021. The actin-disassembly protein glia maturation factor γ enhances actin remodeling and B cell antigen receptor signaling at the immune synapse. Frontiers in Cell and Developmental Biology. 9, 647063. Deretic N, Bolger-Munro M, Choi K, Abraham L, Gold MR. The actin-disassembly protein glia maturation factor γ enhances actin remodeling and B cell antigen receptor signaling at the immune synapse. <i>Frontiers in Cell and Developmental Biology</i>. 2021;9. doi:<a href="https://doi.org/10.3389/fcell.2021.647063">10.3389/fcell.2021.647063</a> Deretic, Nikola, Madison Bolger-Munro, Kate Choi, Libin Abraham, and Michael R. Gold. “The Actin-Disassembly Protein Glia Maturation Factor γ Enhances Actin Remodeling and B Cell Antigen Receptor Signaling at the Immune Synapse.” <i>Frontiers in Cell and Developmental Biology</i>. Frontiers Media, 2021. <a href="https://doi.org/10.3389/fcell.2021.647063">https://doi.org/10.3389/fcell.2021.647063</a>. 152642024-04-03T07:34:08Z2024-04-03T14:10:25Z