CSE1L and NUP37 proximity labeling in MCF10A cells expressing chimeric ErbB1:ErbB2 receptors

This project uses an MCF10A clone (B2B1) expressing chimeric synthetic receptors for ErbB1 (EGFR) and ErbB2 (HER2) along with BirA*-fused inducible alleles of CSE1L or NUP37. Cells were cultured with reconstituted basement membrane, BirA* alleles induced with doxycycline, ErbB receptors dimerized with a synthetic small molecule, and biotinylation was performed for 24 hours. Lysates underwent a two-step biotin affinity purification before gel electrophoresis and mass spectrometry on selected gel fragments.