Figure 1

Figure 1 (A) Schematic representation of a zebrafish heart. The heart consists of a ventricle, atrium, and outflow tract. (B) BirA2-GFP is expressed in cardiomyocytes via the cmlc2 promoter. Section of ventricle from cmlc2:birA2-GFP transgenic animal. BirA2 is distributed throughout the cardiomyocytes, including the nucleus. DAPI staining and native GFP signal are shown. (C) BirA2-GFP-CAAX is expressed in cardiomyocytes via the cmlc2 promoter. Section of ventricle from cmlc2:bira2-GFP-CAAX transgenic animal. The CAAX-tag localizes BirA2 to the membranes of cardiomyocytes. (D) Timeline of biotin administration by intraperitoneal injections (IP injections). (E) Western blot analysis of biotinylation activity of BirA2-GFP-expressing ventricles. BirA2 is functional and biotinylates sufficiently after three daily biotin injections. Endogenous biotinylated carboxylase was detected in untreated and biotin-treated hearts. (F) Western blot analysis of BirA2-GFP-CAAX-expressing ventricles. BirA2 is functional and biotinylates sufficiently after three daily injections with biotin. WT: wild type. (G) Schematic summary of BioID2 assay on uninjured zebrafish hearts. (H) Over-representation test for cellular components. BioID2 for BirA-GFP-CAAX enriches for membrane-associated proteins. 343 total proteins were gated at a 2.5-fold change when normalized to BirA-GFP. p<0.001, false discovery rate (FDR) < 0.015%. dpt: days post treatment. Scale bar in images, 50 μm; magnification scale bar: 10 μm.