Study Of Subcellular Localization Of Tumor Suppressor UBIAD1and The Protein-protein Interactions Among UBIAD1, H-Ras And ApoE

TERE1(Transitional epithelial response gene1) was found and cloned the first timeby Terence W McGarvey et al in2001. Due to the fact that TERE1containing the UbiAprenyltransferase domain containing1, TERE1is also called UBIAD1. UBIAD1gene isubiquitously expressed in normal human tissues. The open reading frame of UBIAD1gene encode a8-10times-helical transmembrane protein of36.8KD and338aminoacids. UBIAD1gene is related with many human diseases, such as transitional cellcarcinoma of the bladder, Schnyder crystalline corneal dystrophy and Parkinson’s disease.However, until now people haven’t known the role of UBIAD1gene in these diseases yet,which may be due to the differences understanding of the UBIAD1protein subcellularlocalization. In our study, we find the UBIAD1protein located on the ER and Golgiapparatus, but not on the membrane. And we find the protein UBIAD1is enriched inGolgi isolated from L02cells. After the subcellular localization of UBIAD1is identified,we began to study its function. We observed the protein UBIAD1, ApoE and H-Ras arecolocalized on the Golgi apparatus. And we observed the fluorescence resonance energytransformation phenomenon among the three proteins. In Co-Immunoprecipitationexperiments, we observed the UBIAD1protein can interact respectly with ApoE andH-Ras, respectly. We also observed that ApoE can induce apoptosis of bladder carcinomaT24cells, which indicates the protein complex, ApoE-UBIAD1-H-Ras, can induceapoptosis of tumor cells.