Moreover, Tissue Inhibitor of MMP (TIMP) overexpression prevents synaptic defects in the Drosophila FXS model (Siller and Broadie, 2011), suggesting that synaptomatrix protease regulation is another avenue worth investigating in the FMRP-Dlp-MMP1 pathway (Dear et al., 2017). The gene discussed is TXNL4B; the disease is fragile X syndrome.