Fig. 1: PL workflow and strategies.
From: Bridging molecular and cellular neuroscience with proximity labeling technologies
a Cells are genetically engineered to express a fusion protein consisting of a POI and a PL enzyme. The enzyme catalyzes the covalent attachment of a biotin substrate to nearby proteins. After labeling, cells are lysed and enzymatically digested into peptides. Biotinylated peptides are enriched using streptavidin and identified by mass spectrometry analysis. b The biotin ligase, activated by ATP, catalyzes the transfer of biotin (B) to nearby proteins, enabling spatially restricted labeling. The POI is fused to the biotin ligase, ensuring selective labeling of proximal proteins. c APEX or HRP is fused to a POI to enable localized labeling. In the presence of H2O2, the peroxidase catalyzes the oxidation of biotin-phenol, generating reactive biotin radicals that covalently label nearby proteins. Created with BioRender.com.
