At the PSD (postsynaptic density), activity-dependent reorganizations of the cortical actin cytoskeleton are hypothesized to play a role in synaptic plasticity. Drebrin-like protein (DBNL) (also referred as Filamentous actin (F-actin)-binding protein 1 (ABP1)), which controls Arp2/3 complex-mediated actin nucleation binds to postsynaptic scaffold proteins of the ProSAP (proline-rich synapse-associated protein 1)/Shank family. This DBNL–ProSAP/Shank complexes serve to connect synaptic signal reception to postsynaptic structural plasticity via rearrangements of the actin cytoskeleton in spines (Haeckel et al. 2008).