Figure 2.

BirA^∗-Txnip expression, activity, and localization. (a) Protein lysates from HEK293 parental (control) or cells stably expressing either BirA^∗-Txnip or BirA^∗-Txnip^C247S were separated by SDS-PAGE and analyzed via immunoblot for transgene expression using myc and Txnip with β-actin as a loading control. Arrowheads indicate the expected size of the BioID transgenes. Cells were pulsed with biotin for 24 hrs prior to lysis and biotinylated proteins were detected by (b) affinity purification and SDS-PAGE/immunoblot and (c) immunocytochemistry. The BioID transgene was detected with myc and biotinylated proteins were detected with streptavidin. Images are representative of 3 biological replicates.