HDMB03 cells were transiently transfected with plasmids expressing NLS-TurboID or 3xHA-TurboID-OTX2 under the control of a strong CAG promoter. After a 15-minute pulse with 500 µM exogenous biotin, RIPA lysates were prepared and processed with streptavin-sepharose to capture biotinylated proteins that were identified by using mass spectrometry.