E3 ubiquitin-protein ligase involved in Golgi membrane fusion and regulation of small GTPases. Acts as a regulator of Golgi membrane dynamics during the cell cycle: recruited to Golgi membrane by Rab proteins and regulates postmitotic Golgi membrane fusion. Acts by mediating ubiquitination during mitotic Golgi disassembly, ubiquitination serving as a signal for Golgi reassembly later, after cell division. Specifically interacts with GTP-bound RAC1, mediating ubiquitination and subsequent degradation of active RAC1, thereby playing a role in host defense against pathogens. May also act as a transcription regulator via its interaction with RARB.
Specificity
Natural and recombinant Bovine E3 ubiquitin-protein ligase HACE1
Subcellular Location
Golgi apparatus Golgi stack membrane Cytoplasm Endoplasmic reticulum A significant portion localizes to the endoplasmic reticulum. Targeted to Golgi membrane via its interaction with Rab proteins.
Interacts with RARB. Interacts with RAB1 (RAB1A, RAB1B or RAB1C), RAB4 (RAB4A or RAB4B) and RAB11 (RAB11A or RAB11B); in a GTP-dependent manner. Interacts with RAC1; in a GTP-dependent manner. Interacts with the 26S proteasomal complex through the 20S core proteasomal subunit.