Identification of the Binding Domains of Nedd4 E3 Ubiquitin Ligase with Its Substrate Protein TMEPAI

摘要

To investigate which domains of Nedd4 are responsible for the interaction with its substrate protein TMEPAI, the plasmids encoding GST-tagged WW domains of Nedd4 and His-HA-tagged TMEPAI were constructed, and the fusion proteins were expressed in E. coli BL21-CodonPlus (DE3)-RIL cells and purified. GST pulldown experiment indicated that Nedd4 directly interacts with His-HA-TMEPAI, and the WW2 and WW3 domains of Nedd4 are responsible for the interaction with TMEPAI, which represents a general mechanism for the interaction between Nedd4 and its substrate protein.