Identification of Redox and Glucose-Dependent Txnip Protein Interactions

Figure 4

Glucose-dependent Txnip expression and protein interactions. HEK293 parental cells acclimated to culture in low glucose media (5 mM) were treated for 24 hrs with increasing glucose concentrations (5, 10, 15, 20, and 25 mM) and protein lysates were analyzed by SDS-PAGE/immunoblot for Txnip with β-actin as a loading control. The arrowhead indicates the expected size of Txnip and densitometry values were determined by the pixel density ratio for Txnip/β-actin. (b) HEK293 parental (control) or cells stably expressing -Txnip were cultured in low glucose (5.5 mM, LG) or high glucose (25 mM, HG) for 24 hrs and then pulsed with biotin. Biotinylated proteins were detected by SDS-PAGE/immunoblot and affinity purification. (c) Affinity purified biotinylated proteins were digested and analyzed by mass spectrometry. -Txnip interactors were classified as static (identified in both LG and HG) or high glucose (only identified in HG). Images are representative of 3 biological replicates.

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