The direct LIMK inhibitor BMS-5 (SYN-1024; Synkinase, San Diego, CA, USA), Y27632 (C3912; Sigma-Aldrich Corp., St. Louis, MO, USA), IPA-3 (3622; Tocris, Bristol, UK), and nicardipine (N7510; Sigma-Aldrich Corp.) were dissolved in dimethyl sulfoxide (DMSO) before they were added to the culture medium. For cells and retinal explants, the final DMSO concentration was 0.5%.
The primary antibodies used were rabbit polyclonal anti-LIMK1 (No. 3842; Cell Signaling Technology, Danvers, MA, USA), rabbit polyclonal anti–phospho-LIMK1 (Thr508)/LIMK2 (Thr505) (No. 3841; Cell Signaling Technology), mouse monoclonal anti–glyceraldehyde-3-phosphate dehydrogenase (GAPDH, 1D4; sc-59540; Santa Cruz, Dallas, TX, USA), mouse monoclonal anti-synaptic vesicle protein 2 (SV2; Developmental Studies Hybridoma Bank, Iowa City, IA, USA), and mouse monoclonal anti-rhodopsin (4D2; MABN15; Millipore, Billerica, MA, USA). The secondary antibodies used were peroxidase-conjugated goat anti-rabbit IgG (111-035-045; Jackson ImmunoResearch, West Grove, PA, USA), peroxidase-conjugated goat anti-mouse IgG + IgM (115-035-068; Jackson ImmunoResearch), Alexa Fluor 488 donkey anti-rabbit IgG (A21206; Life Technologies, Carlsbad, CA, USA), and Alexa Fluor 647 goat anti-mouse IgG (A21236; Life Technologies).